Nebulised hypertonic saline for cystic fibrosis

Peter Wark; Vanessa M McDonald

doi:10.1002/14651858.CD001506.pub4

. 2018 Sep 27;2018(9):CD001506. doi: 10.1002/14651858.CD001506.pub4

Nebulised hypertonic saline for cystic fibrosis

Peter Wark ^1,^✉, Vanessa M McDonald ²

Editor: Cochrane Cystic Fibrosis and Genetic Disorders Group

PMCID: PMC6513595 PMID: 30260472

Abstract

Background

Impaired mucociliary clearance characterises lung disease in cystic fibrosis (CF). Hypertonic saline enhances mucociliary clearance and may lessen the destructive inflammatory process in the airways. This is an update of a previously published review.

Objectives

To investigate efficacy and tolerability of treatment with nebulised hypertonic saline on people with CF compared to placebo and or other treatments that enhance mucociliary clearance.

Search methods

We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group's Cystic Fibrosis Trials Register, comprising references identified from comprehensive electronic database searches, handsearches of relevant journals and abstract books of conference proceedings. We also searched ongoing trials databases.

Date of most recent searches: 08 August 2018.

Selection criteria

Randomised and quasi‐randomised controlled trials assessing hypertonic saline compared to placebo or other mucolytic therapy, for any duration or dose regimen in people with CF (any age or disease severity).

Data collection and analysis

Two authors independently reviewed all identified trials and data, and assessed trial quality. The quality of the evidence was assessed using GRADE.

Main results

A total of 17 trials (966 participants, aged 4 months to 63 years) were included; 19 trials were excluded, three trials are ongoing and 16 are awaiting classification. We judged 14 of the 17 included trials to have a high risk of bias due to participants ability to discern the taste of the solutions.

Hypertonic saline 3% to 7% versus placebo

At four weeks, we found very low‐quality evidence from three placebo‐controlled trials (n = 225) that hypertonic saline (3% to 7%, 10 mL twice‐daily) increased the mean change from baseline of the forced expiratory volume at one second (FEV₁) (% predicted) by 3.44% (95% confidence interval (CI) 0.67 to 6.21), but there was no difference between groups in lung clearance index in one small trial (n = 10). By 48 weeks the effect was slightly smaller in one trial (n = 134), 2.31% (95% CI ‐2.72 to 7.34) (low‐quality evidence). No deaths occurred in the trials. Two trials reporting data on exacerbations were not combined as the age difference between the participants in the trials was too great. One trial (162 adults) found 0.5 fewer exacerbations requiring antibiotics per person in the hypertonic saline group; the second trial (243 children, average age of two years) found no difference between groups (low‐quality evidence). There was insufficient evidence reported across the trials to determine the rate of different adverse events such as cough, chest tightness, tonsillitis and vomiting (very low‐quality evidence). Four trials (n = 80) found very low‐quality evidence that sputum clearance was better with hypertonic saline.

A further trial was performed in adults with an acute exacerbation of lung disease (n = 132). The effects of hypertonic saline on short‐term lung function, 5.10% higher (14.67% lower to 24.87% higher) and the time to the subsequent exacerbation post‐discharge, hazard ratio 0.86 (95% CI 0.57 to 1.30) are uncertain (low‐quality evidence). No deaths were reported. Cough and wheeze were reported but no serious adverse events (very low‐quality evidence).

Hypertonic saline versus mucus mobilising treatments

Three trials compared a similar dose of hypertonic saline to recombinant deoxyribonuclease (rhDNase); two (61 participants) provided data for inclusion in the review. There was insufficient evidence from one three‐week trial (14 participants) to determine the effects of hypertonic saline on FEV₁ % predicted, mean difference (MD) 1.60% (95% CI ‐7.96 to 11.16) (very low‐quality evidence). In the second trial, rhDNase led to a greater increase in FEV₁ % predicted than hypertonic saline (5 mL twice daily) at 12 weeks in participants with moderate to severe lung disease, MD 8.00% (95% CI 2.00 to 14.00) (low‐quality evidence). One cross‐over trial (47 participants) reported 15 exacerbations during treatment with hypertonic saline and 18 exacerbations in the rhDNase group (low‐quality evidence). Increased cough was reported in 13 participants using hypertonic saline and 17 on daily rhDNase in one cross‐over trial of 47 people (low‐quality evidence). There was insufficient evidence to assess rates of other adverse events reported. No deaths were reported.

One trial (12 participants) compared hypertonic saline to amiloride and one (29 participants) to sodium‐2‐mercaptoethane sulphonate. Neither trial found a difference between treatments in any measures of sputum clearance; additionally the comparison of hypertonic saline and sodium‐2‐mercaptoethane sulphonate reported no differences in courses of antibiotics or adverse events (very low‐quality evidence).

One trial (12 participants) compared hypertonic saline to mannitol but did not report lung function at relevant time points for this review; there were no differences in sputum clearance, but mannitol was reported to be more 'irritating' (very low‐quality evidence).

Authors' conclusions

Regular use of nebulised hypertonic saline by adults and children over the age of 12 years with CF results in an improvement in lung function after four weeks (very low‐quality evidence from three trials), but this was not sustained at 48 weeks (low‐quality evidence from one trial). The review did show that nebulised hypertonic saline reduced the frequency of pulmonary exacerbations (although we found insufficient evidence for this outcome in children under six years of age) and may have a small effect on improvement in quality of life in adults.

Evidence from one small cross‐over trial in children indicates that rhDNase may lead to better lung function at three months; qualifying this we highlight that while the study did demonstrate that the improvement in FEV₁ was greater with daily rHDNase, there were no differences seen in any of the secondary outcomes.

Hypertonic saline does appear to be an effective adjunct to physiotherapy during acute exacerbations of lung disease in adults. However, for the outcomes assessed, the quality of the evidence ranged from very low to at best moderate, according to the GRADE criteria.

Plain language summary

Hypertonic saline (salt water with at least 3% salt) nebulised as a fine mist through a mask or mouthpiece for cystic fibrosis

Review question

We reviewed the evidence for treatment with nebulised hypertonic saline compared to placebo or other agents for improving mucus clearance in the lungs of people with cystic fibrosis (CF).

Background

People with CF produce large amounts of thick mucus which is difficult to clear and blocks up their airways. Chest physiotherapy or medication e.g. hypertonic saline, or both combined, are used to try and clear this mucus from the airways. Hypertonic saline is water with a concentration of 3% to 7% salt and is inhaled as a fine mist. This is an update of an earlier review.

Search date

The evidence is current to: 08 August 2018.

Trial characteristics

We included 17 trials with 966 participants with CF aged between 4 months and 63 years. Eleven trials compared hypertonic saline to isotonic saline (water with 0.12 to 0.9% salt (described as placebo (a dummy treatment)); one trial compared isotonic saline and voluntary cough to hypertonic saline or mannitol 300 mg; three trials compared hypertonic saline to rhDNase (Pulmozyme®); one trial compared hypertonic saline to amiloride; and one trial compared hypertonic saline to Mistabron®. Trials assessed different concentrations of hypertonic saline with different nebulisers and different treatment schedules; the most common treatment was twice‐daily 7% hypertonic saline and the most common nebuliser was ultrasonic. Most trials treated people with a bronchodilator to widen the airways before giving the hypertonic saline.

Key results

Hypertonic saline 3% to 7% versus placebo

In three trials (225 people) lung function improved after four weeks, but only one trial (164 people) reported results after 48 weeks, and showed no difference in lung function. No deaths were reported. One adult trial reported fewer exacerbations needing antibiotics with hypertonic saline than with placebo, but a trial in children found no difference in this outcome. There was not enough information to properly assess adverse events such as cough, chest tightness, tonsillitis and vomiting. In four trials (80 participants) sputum clearance was better with hypertonic saline.

One trial in 132 adults with an exacerbation reported uncertain effects of hypertonic saline on short‐term lung function and the time to the next exacerbation after discharge from hospital. No deaths were reported. Side effects such as cough and wheeze were reported, but there were no serious side effects.

Hypertonic saline versus mucus mobilising treatments

We could analyse data from two of the three trials comparing hypertonic saline to rhDNase (61 participants). In one trial there was no difference in lung function at three weeks, but the second reported rhDNase led to a greater increase in lung function at 12 weeks in people with moderate to severe disease. One trial (47 participants) reported no difference in the number of exacerbations, but there was increased cough with hypertonic saline compared to rhDNase. There was not enough information to assess other side effects. No deaths were reported.

One trial (12 participants) compared hypertonic saline to amiloride and one (n = 29) to Mistabron®. Neither trial found a difference between treatments in any measures of sputum clearance. The trial comparing hypertonic saline and Mistabron® also reported no differences in how many antibiotic courses were prescribed or in side effects.

The trial comparing hypertonic saline to mannitol (12 participants) did not report lung function at relevant time points for this review; there were no differences in sputum clearance, but mannitol was reported to be more 'irritating' .

Quality of the evidence

The risks of bias due to people not being randomly chosen to receive different treatments or due to not all results being reported range from low to unclear, but there is a high risk that people knew which treatment they were receiving in half the trials as they could taste the difference between the solutions.

The quality of the evidence was low or very low. Besides the risks of bias, the main problems were the small numbers of participants in trials combined with a wide variation in results; also, some trials limited participants to those who could tolerate hypertonic saline or to certain age groups.

Summary of findings

Background

Description of the condition

Cystic fibrosis (CF) is the most common life‐limiting autosomal recessive genetic disorder in populations of Northern European descent. In 1989 the gene responsible was identified on the long arm of chromosome 7 (Kerem 1989). This gene encodes for a protein named the cystic fibrosis transmembrane conductance regulator (CFTR) which functions as a chloride channel on the surface of epithelial cells. The altered CFTR is thought to result in defects of electrolyte transport which then cause increased water reabsorption across respiratory epithelia. This may lead to dehydration of the airway surface liquid, which in turn may prevent normal clearance of mucus (Davis 1996), although the precise mechanism by which CFTR causes abnormal mucus is still unknown.

Description of the intervention

Improvement of sputum clearance is a major therapeutic aim in CF. Treatments to improve mucus clearance in CF include chest physiotherapy, with and without the addition of agents that enhance mucus clearance. Treatment with nebulised recombinant deoxyribonuclease (rhDNase) has been widely accepted to be of benefit in CF (Yang 2018) and is thought to exert its major effect by enhancing sputum clearance. However, treatment with rhDNase is relatively expensive and its use in most countries is restricted as a consequence. Hypertonic saline may represent a potential alternative or supplementary therapy to improve mucociliary clearance in the context of long‐term maintenance therapy or during times of acute worsening of lung disease in CF.

How the intervention might work

In vitro deposition of hypertonic saline onto the airway surface improves mucus clearance. Dasgupta demonstrated that the addition of 3% hypertonic saline improved measures of sputum clearance and that hypertonic saline had a greater effect on mucus clearance in vitro than rhDNase (Dasgupta 1995). The postulated molecular mechanism of this effect is as follows:

hypertonic saline breaks the ionic bonds within the mucus gel, which could reduce the degree of cross linking and entanglements and lower viscosity and elasticity (Ziment 1978);
with chronic infection the mucin macromolecules develop fixed negative charges, causing increased repulsion; the addition of hypertonic saline increases the ionic concentration of the mucus and causes a conformational change by shielding the negative charges and thereby reducing repulsion ‐ this would result in a more compact mucus macromolecule that would allow more effective clearance (Robinson 1997);
in addition hypertonic saline induces an osmotic flow of water into the mucus layer, rehydrating secretions and thereby improving mucus rheology (Robinson 1997).

Why it is important to do this review

In the long term, improvement in mucociliary function may reduce bacterial load and chronic inflammation within the airways and therefore reduce the decline in lung function that is consequent to this. Hypertonic saline is easy and inexpensive to produce. Therefore, it is important to determine if nebulised hypertonic saline improves outcomes in CF, and to determine the frequency of adverse effects. This is an update of a previously published review (Wark 1999; Wark 2000; Wark 2003; Wark 2009).

Objectives

To investigate efficacy and tolerability of nebulised hypertonic saline treatment in people with CF compared to placebo and or other treatments that enhance mucociliary clearance.

Methods

Criteria for considering studies for this review

Types of studies

Controlled clinical trials. Both random allocation and quasi‐random allocation (e.g. where there is alternate allocation to treatment and control groups) were included.

Types of participants

People of all ages and of both sexes with CF diagnosed clinically or by sweat and genetic testing, including all degrees of disease severity.

Types of interventions

Nebulised hypertonic saline (defined as any concentration of saline greater than or equal to 3% delivered via a mask or mouthpiece with a nebuliser pump) compared to either placebo or usual treatment or any other mucus‐mobilising treatments (including, but not limited to, physical airway clearance techniques and medications which demonstrate improved mucus clearance e.g. rhDNase). Miniumum treatment duration considered in this review is a single dose. Trials comparing hypertonic saline used in conjunction with another intervention would be considered if the comparator group also received the second intervention.

Types of outcome measures

Primary outcomes

Lung function (absolute change and change in per cent (%) predicted)
1. forced expiratory volume at one second (FEV₁)
2. forced vital capacity (FVC)
3. lung volume (residual volume (RV) and total lung capacity (TLC))
4. FEV_0.5
5. lung clearance index (LCI)
Mortality

Secondary outcomes

Measures of sputum clearance (including measures of mucociliary clearance)
Measures of exercise capacity
Measures of quality of life (QoL) and symptoms
Pulmonary exacerbations (where a clear definition is described demonstrating an increase in symptoms or a decline in pulmonary function)
1. frequency
2. admission to hospital
3. duration of hospital stay (post hoc change)
4. outpatient treatments (hospital in the home, unscheduled visits to the doctor)
5. use of antibiotics, either intravenous, oral or inhalational
Medication delivery time (minutes)
Cost of treatment
Adherence to treatment with hypertonic saline along with other treatments after hypertonic saline is added
Bacteriology in pulmonary secretions, including sputum culture, culture from cough swab or bronchial lavage (post hoc change)
Adverse effects such as bronchospasm, cough and acute decline in pulmonary function (acute decline will be limited to the immediate phase of receiving treatment with hypertonic saline to within the first three hours and described separately to longer‐term lung function data as it represents acute bronchospasm provoked by hypertonic saline)

Search methods for identification of studies

We searched for all relevant published and unpublished trials without restrictions on language, year or publication status.

Electronic searches

Relevant trials were identified from the Cochrane Cystic Fibrosis and Genetic Disorders Group's Cystic Fibrosis Trials Register using the term: hypertonic saline.

The Cystic Fibrosis Trials Register is compiled from electronic searches of the Cochrane Central Register of Controlled Trials (CENTRAL) (updated each new issue of theCochrane Library), weekly searches of MEDLINE, a search of Embase to 1995 and the prospective handsearching of two journals ‐ Pediatric Pulmonology and the Journal of Cystic Fibrosis. Unpublished work is identified by searching the abstract books of three major cystic fibrosis conferences: the International Cystic Fibrosis Conference; the European Cystic Fibrosis Conference and the North American Cystic Fibrosis Conference. For full details of all searching activities for the register, please see the relevant sections of the Group's website.

Date of the most recent search of the Group's Cystic Fibrosis Trials Register: 08 August 2018.

We also searched the following trials registries:

US National Institutes of Health Ongoing Trials Register Clinicaltrials.gov (www.clinicaltrials.gov; searched 08 August 2018);

World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) (apps.who.int/trialsearch; searched 08 August 2018).

For details of our search strategies, please see Appendix 1.

Searching other resources

We checked the bibliographies of included studies and any relevant systematic reviews identified for further references to relevant trials.

Data collection and analysis

Selection of studies

The authors (PW and VMM) independently selected the abstracts found during the searches. They then discussed potential and excluded abstracts to reach consensus. If trials were only in abstract form, the review authors contacted the trial authors for additional information. Both review authors then independently reviewed the full trials and, by consensus, included them if they were suitable or excluded them, documenting reasons for exclusion.

Data extraction and management

Two authors (PW and VMM) independently extracted data on trial characteristics and results using standard data acquisition forms. The authors entered the data into the Review Manager software (RevMan 2014).

The authors considered data reported up to and including three months to be short term and data reported at over three months to be long term.

The authors obtained additional data for one trial from the original investigators (Dentice 2016). Where an author of this Cochrane Review was a co‐author on an included trial, a third party performed the data extraction and assessment of quality (both risk of bias and GRADE) for that trial. This occurred when both the current review authors were co‐investigators in the National Hypertonic Saline in Cystic Fibrosis Study trial and Ashley Jones and a second person from the editorial base extracted the data and assessed the risk of bias (Elkins 2006a). This was also the case when one author (PW) was an author on one further trial, when VP and a second person from the editorial base extracted the data and assessed the risk of bias (Dentice 2016).

Assessment of risk of bias in included studies

Two authors assessed the risk of bias of each trial using the Cochrane Handbook for Systeamtic Reviews of Interventions (Higgins 2011). In particular, they examined details of the generation of allocation sequence, the concealment of treatment allocation schedule, whether the trial was blinded, whether intention‐to‐treat (ITT) analyses were possible from available data and if the number of participants lost to follow‐up or subsequently excluded from the trial was recorded.

Measures of treatment effect

If the review authors find that trials do not use a ITT analysis, then they will seek data on the number of participants with each outcome event, by allocated treated group, irrespective of adherence and whether or not the participant was later thought to be ineligible or otherwise excluded from treatment or follow‐up. With regards to dichotomous outcome measures, currently none of the trials report on mortality. For adverse event data, the authors have calculated a pooled estimate of the treatment effect for each outcome across the studies and determined the risk ratio. For the outcome of an improvement of over 10% in FEV₁ reported by two cross‐over trials, the authors used the generic inverse variance to analyse the data and present the odds ratio (OR).

For continuous outcomes, the authors recorded either a mean change from baseline for each group or mean post‐treatment or post‐intervention values and standard deviation (SD) for each group. They calculated a pooled estimate of treatment effect for each of these individually by calculating the mean difference (MD) and 95% confidence intervals (CIs) where appropriate. Where the SD was not reported or available to use, we used the mean difference and 95% CI for each group to calculate the SDs.

We report costs of treatment narratively.

Unit of analysis issues

Where trials measured data longitudinally, the authors based the analysis on the final time point results. Methods do exist to carry out a meta‐analysis of aggregate longitudinal data, where individual patient data (IPD) are not available but these are not available at the moment in RevMan.

For trials with a cross‐over design, at least one week was required to allow sufficient washout of effect, at least for the measures of short‐term outcomes. For these trials of cross‐over design, the authors planned to carry out the analysis using results from a paired analyses, as recommended by Elbourne (Elbourne 2002). This was only possible in one trial (Suri 2001). For the remaining cross‐over trials, the data that were provided in the trial report were not sufficient to carry out this type of analysis. For these trials, we chose to ignore the cross‐over design and treat the results from the two periods as if they were independent (Adde 2004; Amin 2010; Ballmann 1998; Chadwick 1997; Laube 2009; Riedler 1996; Robinson 1996; Robinson 1997; Robinson 1999; Weller 1980). Elbourne reports that using this approach is conservative, due to the fact that it ignores the within‐patient correlation (Elbourne 2002).

Dealing with missing data

The authors originally planned to include missing participants due to dropouts in an ITT analysis The authors attempted to obtain any missing statistics (such as standard deviations (SDs) or correlation coefficients) from the trial authors, or they obtained the original data and determined the statistics. The authors were only able to obtain additional data from two trials (Adde 2004; Dentice 2016). The authors made two attempts to contact authors for missing data before accepting that the additional data would not be made available. However, if the trial authors contact us with data in the future we will add the information to the review at the following update.

Assessment of heterogeneity

The authors tested for heterogeneity between studies using a standard Chi² test and I² statistic (Higgins 2003). The Chi² test is a statistical test for heterogeneity, whereas I² assesses the quantity of inconsistency across studies in the meta‐analysis. The authors accepted a P value of below 0.1. They used the following I² ranges to interpret heterogeneity:

0% to 40%: might not be important;
30% to 60%: may represent moderate heterogeneity;
50% to 90%: may represent substantial heterogeneity;
75% to 100%: considerable heterogeneity.

Assessment of reporting biases

Due to the chronic nature of the disease, in many CF trials investigators collect data longitudinally at different time points throughout the course of the trial. In all the trials the authors examined when data were collected during the trial and also which data were reported in the trial publication. If it appeared that time points were missing, that the review authors would expect to have been reported (based on clinical and biologic plausibility) the review authors would have reported this. The authors also planned to assess publication bias by constructing funnel plots if they had been able to include a sufficient number of trials .

Data synthesis

The authors have used fixed‐effect analyses in this review. For future updates, when appropriate, where between‐trial variability is statistically significant, the authors plan to carry out random‐effects analyses.

Subgroup analysis and investigation of heterogeneity

For future updates, where possible, the authors plan to investigate heterogeneity using subgroup analysis if the I² statistic is over 40%; they will consider the following subgroups:

strength of hypertonic saline (comparing a concentration of 3% to 7% versus a concentration greater than 7%);
volume of hypertonic saline (less than 5 mL versus 5 mL to 10 mL versus more than 10 mL).

Sensitivity analysis

For a future update, when possible, the authors plan to perform a sensitivity analysis based on risk of bias of the trials, excluding those with a high risk of performance bias and including and excluding quasi‐randomised trials.

Summary of findings and quality of the evidence

In a post hoc change in line with current Cochrane guidance, at the 2018 update we added a summary of findings table for each comparison presented in the review (Table 1; Table 2; Table 3; Table 4; Table 5; Table 6). We selected the following seven outcomes to report (chosen based on relevance to clinicians and consumers).

Summary of findings for the main comparison. Hypertonic saline 3% to 7% versus isotonic saline for cystic fibrosis (stable lung disease).

Hypertonic saline 3% to 7% versus isotonic saline for cystic fibrosis (stable lung disease)
Patient or population: adults and children with cystic fibrosis (stable lung disease) Settings: outpatients Intervention: hypertonic saline 3% to 7% Comparison: isotonic saline
Outcomes	*Illustrative comparative risks (95% CI)**		Relative effect  (95% CI)	No of participants  (trials)	Quality of the evidence  (GRADE)	Comments
	Assumed risk	Corresponding risk
	Isotonic saline	Hypertonic saline 3% to 7%
FEV₁ (% predicted) change from baseline, short term Follow‐up: 4 weeks	The mean change in FEV₁ (% predicted) ranged from ‐1.42 to 2.8 in the isotonic saline groups.	The mean change in FEV₁ (% predicted) was 3.44 higher (0.67 higher to 6.21 higher) in the hypertonic saline group.	NA	225 (3 trials)¹	⊕⊝⊝⊝  very low^{2, 4, 5, 6}
FEV₁ (% predicted) change from baseline, long term Follow‐up: 48 weeks	The mean change in FEV₁ (% predicted) was 2.44 in the isotonic saline group.	The mean change in FEV₁ (% predicted) was 2.31 higher (2.72 lower to 7.34 higher) in the hypertonic saline group.	NA	134 (1 trial)	⊕⊕⊝⊝  low^{2, 3}	The included trial also measured change in FEV₁ (% predicted) at: 12 weeks, MD 4.10 (95% CI ‐0.08 to 8.28); 24 weeks, MD 5.37 (95% CI 1.03 to 9.71); and 36 weeks, MD 3.63 (95% CI ‐1.56 to 8.82).
LCI Follow‐up: 4 weeks	The mean LCI was 8.89 in the isotonic saline group.	The mean LCI was 1.03 lower (2.76 lower to 0.70 higher) in the hypertonic saline group.	NA	10 (1 trial)	⊕⊝⊝⊝  very low^{5, 7}	Trial had a cross‐over design.
Mortality	Outcome not reported.		NA	NA	NA
Measures of sputum clearance Follow‐up: up to 24 hours	The trials used radio‐labelled aerosol clearance and an 'area under the curve' measure to assess mucociliary clearance. Both measures significantly favoured treatment with hypertonic saline.		NA	80  (4 trials)	⊕⊝⊝⊝  very low^{2, 4, 5}	All trials had cross‐over design.
Pulmonary exacerbations Follow‐up: up to 48 weeks	One trial showed that there were fewer exacerbations per year requiring intravenous antibiotic therapy in the hypertonic saline group than in the isotonic saline group and that the interval during which participants remained free of exacerbations was also significantly longer in the hypertonic saline group. The second trial found no significant differences in the mean number of exacerbations per year. There was no difference reported in hospitalisation rates between the hypertonic saline group and the controls.		NA	415 (2 trials)	⊕⊕⊝⊝  low^{2, 8}
Adverse events Follow up: up to 48 weeks	There were no significant difference between treatment groups in adverse events including cough, chest tightness, pharyngitis, haemoptysis, sinusitis, sneezing, tonsillitis and vomiting		NA	589 (6 trials)⁹	⊕⊝⊝⊝  very low^{2, 4, 5}
The basis for the assumed risk* (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).  CI: confidence interval; FEV₁: forced expiratory volume in 1 second;LCI: lung clearance index; MD: mean difference; NA: not applicable.
GRADE Working Group grades of evidence  High quality: further research is very unlikely to change our confidence in the estimate of effect.  Moderate quality: further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.  Low quality: further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.  Very low quality: we are very uncertain about the estimate.

Hypertonic saline compared with rhDNase with for cystic fibrosis
Patient or population: adults and children with cystic fibrosis Settings: outpatients Intervention: hypertonic saline (daily) Comparison: rhDNase (daily)¹
Outcomes	*Illustrative comparative risks (95% CI)**		Relative effect  (95% CI)	No of participants  (trials)	Quality of the evidence  (GRADE)	Comments
	Assumed risk	Corresponding risk
	rhDNase	Hypertonic saline
FEV₁ (% predicted) change from baseline, short term Follow‐up: 3 weeks	The mean change from baseline in FEV₁ (% predicted) was 1.6% higher (7.96% lower to 11.16% higher) in the hypertonic saline group compared to the daily rhDNase group.²		NA	14  (1 trial)	⊕⊝⊝⊝  very low^3,4,5	Trial had a cross‐over design. No significant difference in the primary outcome (lung function) at this time‐point, with improvements only in secondary outcomes.
FEV₁ (% predicted) change from baseline, long term Follow‐up: 3 months	The mean change from baseline in FEV₁ (% predicted) was 8% higher (2% higher to 14% higher) in the hypertonic saline group compared to the daily rhDNase group.²		NA	47  (1 trial)	⊕⊝⊝⊝  very low^2,6,7	Trial had a cross‐over design. An additional cross‐over trial of 18 participants found no difference between treatments in FEV₁ after 10 weeks (no data presented).
LCI	Outcome not reported.		NA	NA	NA
Mortality	Outcome not reported.		NA	NA	NA
Measures of sputum clearance	Outcome not reported.		NA	NA	NA
Pulmonary exacerbations Follow‐up: NA	15 episodes occurring during treatment with hypertonic saline and 18 with daily rhDNase, there was no statistical difference between treatments (see comment).		NA	47  (1 trial)	⊕⊝⊝⊝  very low^2,6,7	Trial had a cross‐over design. Number of episodes reported rather than the number of participants with exacerbations (leading to a unit of analysis issue) so data not entered into the analysis.
Adverse events Follow up: 3 months	Increased cough was reported in 13 participants using hypertonic saline and 17 on daily rhDNase. There were similar rates of other adverse events between treatment arms (see comment).		NA	47  (1 trial)	⊕⊝⊝⊝  very low^2,6,7	Trial had a cross‐over design, so data not entered into analysis.
The basis for the assumed risk* (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).  CI: confidence interval; FEV₁: forced expiratory volume in 1 second; LCI: lung clearance index; MD: mean difference; NA: not applicable.
GRADE Working Group grades of evidence  High quality: further research is very unlikely to change our confidence in the estimate of effect.  Moderate quality: further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.  Low quality: further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.  Very low quality: we are very uncertain about the estimate.

Hypertonic saline compared with amiloride for cystic fibrosis
Patient or population: adults and children with cystic fibrosis Settings: outpatients Intervention: hypertonic saline Comparison: amiloride
Outcomes	*Illustrative comparative risks (95% CI)**		Relative effect  (95% CI)	No of Participants  (studies)	Quality of the evidence  (GRADE)	Comments
	Assumed risk	Corresponding risk
	Amiloride	Hypertonic saline
FEV₁: change from baseline, short term	Outcome not reported.		NA	NA	NA
FEV₁: change from baseline, long term	Outcome not reported.		NA	NA	NA
LCI	Outcome not reported.		NA	NA	NA
Mortality	Outcome not reported.		NA	NA	NA
Measures of sputum clearance Follow‐up: 60 minutes	There was no significant difference between treatment groups.		NA	12  (1 trial)	⊕⊝⊝⊝  very low^1,2,3	Trial had cross‐over design.
Pulmonary exacerbations	Outcome not reported.		NA	NA	NA
Adverse events	Outcome not reported.		NA	NA	NA
The basis for the assumed risk* (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).  CI: confidence interval; FEV₁: forced expiratory volume in 1 second; LCI: lung clearance index; NA: not applicable.
GRADE Working Group grades of evidence  High quality: further research is very unlikely to change our confidence in the estimate of effect.  Moderate quality: further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.  Low quality: further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.  Very low quality: we are very uncertain about the estimate.

Hypertonic saline compared with sodium‐2‐mercaptoethane sulphonate (Mistabron®) for cystic fibrosis
Patient or population: adults and children with cystic fibrosis Settings: outpatients Intervention: hypertonic saline Comparison: sodium‐2‐mercaptoethane sulphonate
Outcomes	*Illustrative comparative risks (95% CI)**		Relative effect  (95% CI)	No of participants  (trials)	Quality of the evidence  (GRADE)	Comments
	Assumed risk	Corresponding risk
	Sodium‐2‐mercaptoethane sulphonate	Hypertonic saline
FEV₁: short term	Outcome not reported.		NA	NA	NA
FEV₁: long term	Outcome not reported.		NA	NA	NA
LCI	Outcome not reported.		NA	NA	NA
Mortality	Outcome not reported.		NA	NA	NA
Measures of sputum clearance Follow‐up: 2 months	No significant difference in sputum volume, colour or cough frequency between the groups.		NA	29  (1 trial)	⊕⊝⊝⊝  very low^1,2,3	Trial had cross‐over design.
Pulmonary exacerbations Follow‐up: 2 months	See comment.		NA	29  (1 trial)	⊕⊝⊝⊝  very low^1,2,3	Trial had cross‐over design. The only information provided relevant to this outcome was that there was no change in the number of courses of antibiotics prescribed.
Adverse events Follow‐up: 2 months	See comment.		NA	29  (1 trial)	⊕⊝⊝⊝  very low^1,2,3	Trial had cross‐over design. Participants in both treatment groups described coughing at the beginning of their inhalations. No serious adverse events occurred during the trial.
The basis for the assumed risk* (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).  CI: confidence interval; FEV₁: forced expiratory volume in 1 second; LCI: lung clearance index; NA: not applicable.
GRADE Working Group grades of evidence  High quality: further research is very unlikely to change our confidence in the estimate of effect.  Moderate quality: further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.  Low quality: further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.  Very low quality: we are very uncertain about the estimate.

Hypertonic saline compared with mannitol for cystic fibrosis
Patient or population: adults and children with cystic fibrosis Settings: outpatients Intervention: hypertonic saline Comparison: mannitol
Outcomes	*Illustrative comparative risks (95% CI)**		Relative effect  (95% CI)	No of participants  (trials)	Quality of the evidence  (GRADE)	Comments
	Assumed risk	Corresponding risk
	Mannitol	Hypertonic saline
FEV₁: short term Follow‐up: up to 95 minutes	See comment.		NA	12  (1 trial)	⊕⊝⊝⊝  very low^1,2,3	Trial had cross‐over design. FEV₁ was assessed in the included trial at 5 minutes and 95 minutes post‐intervention. These very short‐term time‐points are not of clinical relevance to this review. Change from baseline within‐groups was reported but no between‐group data.
FEV₁: long term	Outcome not reported.		NA	NA	NA
LCI	Outcome not reported.		NA	NA	NA
Mortality	Outcome not reported.		NA	NA	NA
Measures of sputum clearance Follow‐up: up to 95 minutes	There was no significant difference between treatment groups for matched voluntary cough.		NA	12  (1 trial)	⊕⊝⊝⊝  very low^1,2,4	Trial had cross‐over design.
Pulmonary exacerbations	Outcome not reported.		NA	NA	NA
Adverse events Follow up: up to 95 minutes	See comment.		NA	12  (1 trial)	⊕⊝⊝⊝  very low^1,2,4	Trial had cross‐over design. Mannitol was considered to be a more 'irritating' treatment than other treatments (4‐armed trial); no specific data given.
The basis for the assumed risk* (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).  CI: confidence interval; FEV₁: forced expiratory volume in 1 second; LCI: lung clearance index; NA: not applicable.
GRADE Working Group grades of evidence  High quality: further research is very unlikely to change our confidence in the estimate of effect.  Moderate quality: further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.  Low quality: further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.  Very low quality: we are very uncertain about the estimate.

Date	Event	Description
11 September 2018	New search has been performed	A major update of the review was conducted with 90 new references identified from searches of the Cochrane Cystic Fibrosis and Genetic Disorders Trials Register, clinicaltrials.gov and the WHO ICTRP. New trials Five important new trials (24 references) have been included (Amin 2010; Dentice 2016; Laube 2009; Mainz 2015; Rosenfeld 2012). This increased the number of participants in the trial from 442 to 966. Nine new trials (27 references) have also been excluded (Brivio 2016; Buonpensiero 2010; DeCono 2008; Dentice 2012; EUCTR2007‐002707‐40‐BE; Grasemann 2013; IRCT20180307038994N1; NCT01094704; O'Neill 2017; Ros 2012; San Miguel 2016; Van Ginderdeuren 2008; Van Ginderdeuren 2011). 16 newly identified trials (21 references) are currently awaiting assessment until further information is available to allow inclusion or exclusion (Amin 2016; Balinotti 2015; Brown 2010; Corcoran 2017; Donaldson 2013; Dwyer 2013; Hofmann 1997; NCT00928135; NCT01355796; NCT01377792; NCT01619657; NCT02378467; NCT03391414; Nenna 2017; Palacio 2014; PRESIS 2018). Three new trials (four references) are listed as ongoing (NCT02276898; NCT02343445; NCT02950883). Previously identified trials 11 additional references have been added to five already included trials (Elkins 2006a; Eng 1996; Robinson 1997; Robinson 1999; Weller 1980). One additional reference has been added to an already excluded trial (Donaldson 2006). Two trials (two references) which were previously listed as 'Awaiting classification' have been excluded (Elkins 2006b; Vanlaethem 2008). An additional reference to the Elkins trial was identified in the latest searches. One trial (one reference) previously excluded has been moved to 'Awaiting classification' pending further information (Hofmann 1997).
11 September 2018	New citation required and conclusions have changed	The conclusions have been amended in light of the new evidence. The addition of new data has allowed us to conclude that hypertonic saline appears to be an effective adjunct to physiotherapy during acute exacerbations of lung disease in adults.

Date	Event	Description
26 April 2010	Amended	Contact details updated.
31 December 2008	New citation required and conclusions have changed	A large multi‐centre trial has been included in the review, resulting in the conclusions being updated (Elkins 2006a).
31 December 2008	New search has been performed	A search of the Group's trials register identified two new eligible trials (Cardinale 2003; Elkins 2006a). These trials have now been included in the review. A trial previously listed in Studies awaiting classification has now been included in the review (Adde 2004). Two studies identified by the searches have now been excluded from the review (Donaldson 2006; Kobylyansky 2000). A further reference to the already included Suri trial has been added (Suri 2001). Two trials have been added to Studies awaiting classification (Elkins 2006b; Vanlaethem 2008).
12 November 2008	Amended	Converted to new review format.
2 May 2005	New citation required but conclusions have not changed	No new trials have been included. One trial is currently awaiting assessment (Adde 2004). Individual patient data have kindly been provided by Dr Adde and will be included in a future update of the review. Further data have been included for the Suri trial (Suri 2001). The layout of the analysis has been changed from the previous updates to ensure clarity for the reader.
2 October 2003	New search has been performed	Six additional references to the already included Suri trial have been added (Suri 2001). This did not add greatly to the data already present. Two of the references looked at the cost of treatment with HS and rhDNase and additional data has been added. One other reference looked at the effect of rhDNase and HS on airway inflammation and the data has now been included.  The other references did not add to the data already presented. One additional reference to the already included Ballmann trial has been added (Ballmann 1998). No additional data has been included in the review. One additional reference to the already included Riedler trial has been added (Riedler 1996). No additional data has been included in the review.
3 November 2002	New search has been performed	An additional trial was found and incorporated in the review (Suri 2001). This was a relatively large clinical trial comparing hypertonic saline and rhDNase. Significant changes have been made to the review.
3 November 2001	New search has been performed	With this update significant changes to style were made particularly in the order of the outcomes and the presentation of the results. The Suri trial was added and this contained a large amount of additional information particularly concerning the effect of hypertonic saline versus DNase on lung function (Suri 2001).

Database or Resource	Strategy
Clinicaltrials.gov	[Advanced Search Form] Other Terms: hypertonic Study Type: Interventional Studies Condition/ Disease: cystic fibrosis
WHO ICTRP	cystic fibrosis AND hypertonic

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Change in FEV₁ (% predicted)	3		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
1.1 At 2 ‐ 4 weeks (all participants)	3	225	Mean Difference (IV, Fixed, 95% CI)	3.44 [0.67, 6.21]
1.2 At 2 ‐ 4 weeks (participants aged 14 years and over)	2	205	Mean Difference (IV, Fixed, 95% CI)	4.15 [1.14, 7.16]
1.3 At 2 ‐ 4 weeks (children FEV₁ > 80% predicted)	1	20	Mean Difference (IV, Fixed, 95% CI)	‐0.42 [‐7.45, 6.61]
1.4 At 12 weeks	1	149	Mean Difference (IV, Fixed, 95% CI)	4.1 [‐0.08, 8.28]
1.5 At 24 weeks	1	140	Mean Difference (IV, Fixed, 95% CI)	5.37 [1.03, 9.71]
1.6 At 36 weeks	1	134	Mean Difference (IV, Fixed, 95% CI)	3.63 [‐1.56, 8.82]
1.7 At 48 weeks	1	134	Mean Difference (IV, Fixed, 95% CI)	2.31 [‐2.72, 7.34]
2 Change in FVC (% predicted)	3		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
2.1 At 2 ‐ 4 weeks	3	225	Mean Difference (IV, Fixed, 95% CI)	1.07 [‐1.63, 3.78]
2.2 At 12 weeks	1	141	Mean Difference (IV, Fixed, 95% CI)	4.56 [0.79, 8.33]
2.3 At 24 weeks	1	140	Mean Difference (IV, Fixed, 95% CI)	3.64 [0.17, 7.11]
2.4 At 36 weeks	1	134	Mean Difference (IV, Fixed, 95% CI)	3.40 [‐0.82, 7.62]
2.5 At 48 weeks	1	134	Mean Difference (IV, Fixed, 95% CI)	2.76 [‐1.09, 6.61]
3 Mean change in FEV_0.5 (mL)	1		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
3.1 At 48 weeks	1	45	Mean Difference (IV, Fixed, 95% CI)	41.0 [0.96, 81.04]
4 Lung clearance index (LCI)	1		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
4.1 At 4 weeks	1	19	Mean Difference (IV, Fixed, 95% CI)	‐1.03 [‐2.76, 0.70]
5 Radiolabelled isotope clearance	3		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
5.1 At 60 mins	3	68	Mean Difference (IV, Fixed, 95% CI)	6.14 [2.56, 9.72]
6 Mucociliary clearance measured as area under the curve	2		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
6.1 Single dose	2	44	Mean Difference (IV, Fixed, 95% CI)	‐212.06 [‐271.64, ‐152.48]
7 Exercise capacity (using a subjective visual analogue score)	1		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
7.1 At Week 1	1	52	Mean Difference (IV, Fixed, 95% CI)	0.88 [0.19, 1.57]
7.2 At Week 2	1	52	Mean Difference (IV, Fixed, 95% CI)	1.01 [0.18, 1.84]
8 Feeling of cleared chest (using a subjective visual analogue scale)	2		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
8.1 At up to Week 1	2	72	Mean Difference (IV, Fixed, 95% CI)	0.97 [0.35, 1.60]
9 Quality of life (change from baseline)	3		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
9.1 CFQ parent	3	365	Mean Difference (IV, Fixed, 95% CI)	1.62 [‐1.69, 4.92]
9.2 CFQ 14+	1	91	Mean Difference (IV, Fixed, 95% CI)	7.77 [1.86, 13.68]
9.3 SF36	1	91	Mean Difference (IV, Fixed, 95% CI)	2.84 [‐7.90, 13.58]
10 Average number of exacerbations	2		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
10.1 Number requiring antibiotics	2	415	Mean Difference (IV, Fixed, 95% CI)	‐0.23 [‐0.48, 0.02]
10.2 Number of visits not requiring antibiotics	1	162	Mean Difference (IV, Fixed, 95% CI)	‐0.25 [‐0.84, 0.34]
11 Average number of hospital admissions per participant	1		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
11.1 At 48 weeks	1	162	Mean Difference (IV, Fixed, 95% CI)	‐0.13 [‐0.48, 0.22]
12 Adverse events: acute fall in lung function	2		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
12.1 Acute fall in FEV₁ % predicted	1	24	Mean Difference (IV, Fixed, 95% CI)	5.2 [‐0.59, 10.99]
12.2 Acute fall in FEV₁ mL	1	19	Mean Difference (IV, Fixed, 95% CI)	75.0 [‐31.49, 181.49]
13 Change in log10 colony forming units (GFU)/g from baseline at final visit	1		Mean Difference (IV, Fixed, 95% CI)	Totals not selected
13.1 P. aeruginosa	1		Mean Difference (IV, Fixed, 95% CI)	0.0 [0.0, 0.0]
13.2 S. aureus	1		Mean Difference (IV, Fixed, 95% CI)	0.0 [0.0, 0.0]
14 Adverse events	2		Risk Ratio (M‐H, Fixed, 95% CI)	Subtotals only
14.1 Cough	2	373	Risk Ratio (M‐H, Fixed, 95% CI)	1.03 [0.78, 1.35]
14.2 Pharyngitis	1	52	Risk Ratio (M‐H, Fixed, 95% CI)	2.79 [0.12, 65.38]
14.3 Chest tightness	2	373	Risk Ratio (M‐H, Fixed, 95% CI)	0.66 [0.11, 3.98]
14.4 Haemoptysis	1	52	Risk Ratio (M‐H, Fixed, 95% CI)	0.93 [0.21, 4.17]
14.5 Vomiting	1	321	Risk Ratio (M‐H, Fixed, 95% CI)	0.52 [0.13, 2.03]
14.6 Wheezing	1	321	Risk Ratio (M‐H, Fixed, 95% CI)	2.06 [0.38, 11.11]
14.7 Fever	1	321	Risk Ratio (M‐H, Fixed, 95% CI)	0.99 [0.58, 1.68]
14.8 Nasal congestion	1	321	Risk Ratio (M‐H, Fixed, 95% CI)	0.76 [0.42, 1.37]
14.9 Ear infection	1	321	Risk Ratio (M‐H, Fixed, 95% CI)	1.40 [0.78, 2.51]
14.10 Acquisition of Burkholderia cepacia	1	321	Risk Ratio (M‐H, Fixed, 95% CI)	1.03 [0.15, 7.23]

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Change in FEV₁ from baseline (% predicted)	1		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
1.1 At day 7	1	130	Mean Difference (IV, Fixed, 95% CI)	3.95 [‐16.69, 24.59]
1.2 At day 10	1	99	Mean Difference (IV, Fixed, 95% CI)	‐2.70 [‐24.69, 19.29]
1.3 At discharge	1	130	Mean Difference (IV, Fixed, 95% CI)	5.10 [‐14.67, 24.87]
2 Change in FVC from baseline (% predicted)	1		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
2.1 At day 7	1	130	Mean Difference (IV, Fixed, 95% CI)	1.10 [‐5.74, 7.94]
2.2 At day 10	1	99	Mean Difference (IV, Fixed, 95% CI)	7.90 [‐1.86, 17.66]
2.3 At discharge	1	130	Mean Difference (IV, Fixed, 95% CI)	6.10 [‐0.68, 12.88]
3 Shuttle walk test	1		Mean Difference (IV, Fixed, 95% CI)	Subtotals only
3.1 At day 7	1	132	Mean Difference (IV, Fixed, 95% CI)	46.0 [‐14.81, 106.81]

Outcome or subgroup title	No. of studies	Statistical method	Effect size
1 Change in FEV₁ (% predicted)	2	Treatment difference (Fixed, 95% CI)	Totals not selected
1.1 At 3 weeks	1	Treatment difference (Fixed, 95% CI)	0.0 [0.0, 0.0]
1.2 At 3 months	1	Treatment difference (Fixed, 95% CI)	0.0 [0.0, 0.0]
2 Improvement in FEV₁ >10%	2	Odds Ratio (Fixed, 95% CI)	Totals not selected
2.1 At 3 weeks	1	Odds Ratio (Fixed, 95% CI)	0.0 [0.0, 0.0]
2.2 At 3 months	1	Odds Ratio (Fixed, 95% CI)	0.0 [0.0, 0.0]
3 Change in FVC (% predicted)	1	Treatment difference (Fixed, 95% CI)	Totals not selected
3.1 At 3 months	1	Treatment difference (Fixed, 95% CI)	0.0 [0.0, 0.0]
4 Exercise tolerance ‐ oxygen saturation	1	Treatment difference (Fixed, 95% CI)	Totals not selected
4.1 At 3 months	1	Treatment difference (Fixed, 95% CI)	0.0 [0.0, 0.0]
5 Exercise tolerance ‐ VAS for breathlessness	1	Treatment difference (Fixed, 95% CI)	Totals not selected
5.1 At 3 months	1	Treatment difference (Fixed, 95% CI)	0.0 [0.0, 0.0]
6 Exercise tolerance ‐ FCS	1	Treatment difference (Fixed, 95% CI)	Totals not selected
6.1 At 3 months	1	Treatment difference (Fixed, 95% CI)	0.0 [0.0, 0.0]
7 Mean percentage change in quality of life score	1	Treatment difference (Fixed, 95% CI)	Totals not selected
7.1 At 3 months	1	Treatment difference (Fixed, 95% CI)	0.0 [0.0, 0.0]
8 Delivery time (minutes)	1	Mean Difference (IV, Fixed, 95% CI)	Totals not selected

Methods	Open‐label, randomised trial. Design: cross‐over with 4 weeks in each treatment arm and a 2‐week washout period in between. Location: Brazil (single centre).
Participants	Total participants: n = 18, 5 male and 13 female. CF diagnosis: not stated. Age: mean (SD) 14.8 (4.8) years, range 8.7 to 25.8 years. Baseline characteristics Airway colonization: Pseudomonas aeruginosa = 17 Staphylococcus aureus = 12 Haemophylus influenzae = 1 Shwachman score: median (range) 65 (55 – 90). Pancreatic insufficiency: n = 17. Previous use of DNase: n = 15. Continuous inhaled gentamicin therapy: n = 11.
Interventions	Group 1: HS 6% 10 mL. Group 2: rhDnase 2.5 mg 2x daily. Both trial drugs were delivered by a Pari LC Plus nebulizer with a Proneb® compressor, by a mouthpiece. The first inhalation was done in the hospital, for technique supervision, checking of immediate side effects, post‐medication PFT and measurement of nebulization time. Salbutamol (400 mcg) was given prior to inhalation, twice daily, in both arms of the trial. All the other treatment for CF was unchanged. While in the rhDnase arm of the trial the participant was asked to do a normal saline nebulization (5 mL) at another time during the day.
Outcomes	Change in FEV₁, sputum culture bacterial growth, invitro studies of mucus, symptom score, satisfaction with treatment.
Notes	Abstract only, but some additional information from authors. No sample size calculation stated.
*Risk of bias*
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	No detail provided in abstract, but additional information from authors confirmed use of a random numbers table.
Allocation concealment (selection bias)	Low risk	No detail provided in abstract, but additional information from authors confirmed that for each potential participant the selected sequence of treatment was defined and written in a piece of paper which was then put into numbered envelopes that were kept in the hospital pharmacy. After participants were recruited and informed consent obtained the first envelope was opened and read to see the allocated treatment.
Blinding of participants and personnel (performance bias)   All outcomes	High risk	Double blind, participant blinding was attempted by masking the taste of the solutions with quinine sulphate but additional info states "as participants were well aware of the medication flavour of HS this could not be masked".
Blinding of outcome assessment (detection bias)   All outcomes	Unclear risk	Not discussed.
Incomplete outcome data (attrition bias)   All outcomes	Low risk	Did not report withdrawals. Additional data provided stated that 1 participant (not included in the analysis) had to stop treatment with HS due to severe dyspnoea during its nebulization.
Selective reporting (reporting bias)	Unclear risk	Abstract only.
Other bias	Low risk	2‐week washout period in between treatment arms. No sample size calculation stated.

Methods	Randomised controlled trial. Design: cross‐over with 2 treatment periods of 3 weeks each and a washout period of 3 weeks in between. Location: Germany.
Participants	Total participants: n = 14, 8 males and 6 females.  FEV₁ % predicted had to be greater than 40%. Baseline characteristics: FEV₁ % predicted: mean (SD) 75.6% (14%).  Pseudomonas aeruginosa: chronic colonisation: n = 9 free: n = 3 intermittent: n = 2
Interventions	Pre‐treated salbutamol 200 mcg MDI inhaled (2 puffs).  Group 1: 10 mL HS 5.85% 2x daily. Group 2: 2 mL Pulmozyme 2.5 mg 2x daily. Routine medication not altered during trial.
Outcomes	Change in FEV₁ as a % of predicted, nebulisation time, comparison of cost (in Deutschmarks), preference.
Notes	There was a 3‐week washout between interventions. No sample size calculation stated.
*Risk of bias*
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Participants randomised into groups of 4 and drew lots to start with HS or rhDNase.
Allocation concealment (selection bias)	Unclear risk	No details provided as to how lots concealed allocation.
Blinding of participants and personnel (performance bias)   All outcomes	High risk	Taste of HS and difference in volume made blinding not possible.
Blinding of outcome assessment (detection bias)   All outcomes	Unclear risk	Not discussed.
Incomplete outcome data (attrition bias)   All outcomes	Unclear risk	No information provided whether an ITT was used.
Selective reporting (reporting bias)	Low risk	All outcomes stated in the 'Methods' section reported in the 'Results' section.
Other bias	Low risk	Washout period of 3 weeks.  No sample size calculation stated.

Methods	Randomised placebo‐controlled trial. Design: parallel. Location: Italy.
Participants	Total participants: n = 25. Treatment group: n = 12. Placebo group: n = 13. Baseline characteristics: stable disease.
Interventions	Group 1: HS 7%. Group 2: IS 0.09%. Frequency of nebulization not stated.
Outcomes	Change in lung function and exhaled nitric oxide measures, cough, sputum production. Measurements at baseline and 2 weeks.
Notes	Abstract only. No sample size calculation stated.
*Risk of bias*
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No detail provided.
Allocation concealment (selection bias)	Unclear risk	No detail provided.
Blinding of participants and personnel (performance bias)   All outcomes	Unclear risk	No detail provided.
Blinding of outcome assessment (detection bias)   All outcomes	Unclear risk	No detail provided.
Incomplete outcome data (attrition bias)   All outcomes	High risk	Cardinale stated that no adverse events were reported with HS, but no information given for IS group.
Selective reporting (reporting bias)	Unclear risk	Abstract only, no detail provided.
Other bias	Unclear risk	No sample size calculation stated.

Methods	Randomised trial. Design: cross‐over with 3 arms.
Participants	Total participants: n = 15. Groups stratified according to FEV₁ (over 70% and 40% ‐ 70%).
Interventions	Group 1: IS. Group 2: HS 3.5%. Group 3: hypotonic saline.
Outcomes	Change in FEV₁ % predicted, nebulisation.
Notes	Abstract only. No sample size calculation stated.
*Risk of bias*
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No detail provided.
Allocation concealment (selection bias)	Unclear risk	No detail provided.
Blinding of participants and personnel (performance bias)   All outcomes	High risk	Stated as single blind, possibly assessors who were blinded due to difficulties in masking taste of intervention, but not clear.
Blinding of outcome assessment (detection bias)   All outcomes	Unclear risk	Stated as single blind, possibly assessors who were blinded due to difficulties in masking taste of intervention, but not clear.
Incomplete outcome data (attrition bias)   All outcomes	Unclear risk	No description of any dropouts given.
Selective reporting (reporting bias)	Unclear risk	Abstract only, no detail provided.
Other bias	Unclear risk	No sample size calculation stated. No washout period stated.

Methods	Randomised trial. Design: cross‐over trial with 4 weeks treatment in each arm and 4‐week washout period. Location: Canada (multicentre).
Participants	Total participants: n = 20 randomised, 1 excluded from analysis. 7 males and 12 females. CF diagnosis ? Mean (SD) age at baseline = 10.6 (3.1) years. Baseline characteristics Pseudomonas aeruginosa +ve: n = 7  BMI: mean (SD) 17.0 (3.0)  Pancreatic insufficient: 84%  DF508/DF508: 42%  DF508 compound heterozygous: 21%  Lung function: FVC % predicted: mean (SD) 101 (11.3), range (81 to 121) FEV₁ % predicted: mean (SD) 96 (12), range(80 to 118) FEF25‐75% predicted: mean (SD) 84 (24), range (53 to 120
Interventions	Group 1: 4 mL HS 7% 2x daily. Group 2: 4 mL IS 0.9% 2x daily. The solutions were administered using the PARI LC Star nebulizer. 2x 100 mg puffs of salbutamol (Ventolin) were administered before each inhalation of study solution using a holding chamber.
Outcomes	LCI, CFQ‐R. FEV₁, FVC, FEF _25‐75.
Notes	Investigators calculated the sample size required for testing using HS as the main exposure variable and the LCI as the primary outcome variable.
*Risk of bias*
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Concealed computer‐generated randomisation.
Allocation concealment (selection bias)	Low risk	Randomisation concealed as performed by a research pharmacist not otherwise involved in the trial.
Blinding of participants and personnel (performance bias)   All outcomes	High risk	The solutions were indistinguishable from each other in appearance but participants could discern a difference in taste between solutions. High risk with this cross‐over design.
Blinding of outcome assessment (detection bias)   All outcomes	Low risk	Blinding of researchers.
Incomplete outcome data (attrition bias)   All outcomes	Low risk	20 recruited, details of missing data for 3 participants described (as follows), complete cross‐over data were therefore available for 17 participants. The LCI results of 1 participant failed to meet the quality control criteria for all 4 trial visits and were therefore excluded from the analysis. 1 participant receiving IS withdrew from the trial after completion of the initial 4‐week trial period because of difficulties complying with the trial protocol. 1 participant had uninterpretable LCI data at visit 2.
Selective reporting (reporting bias)	Low risk	All outcomes stated in the 'Methods' section reported in the 'Results' section.
Other bias	Low risk	4‐week washout period.  Investigators calculated the sample size.

Methods	Randomised controlled trial. Design: parallel. Duration: 3‐day study which began towards the end of hospitalisation for an exacerbation (approximately 14 days) with follow up for 1 year. If readmission within that year, participant invited to repeat 3‐day study. Location: Australian multicentre trial.
Participants	132 adults with CF admitted to hospital with a respiratory exacerbation. Age: mean (SD) 28 (9) years. 49% were female. FEV₁ % predicted: mean (SD) 48 (20)%.
Interventions	Group 1: 3x daily nebulisation of 4 mL HS 7%. Group 2: IS 0.12% (taste‐masked). Interventions given immediately before or during physiotherapy.
Outcomes	Length of hospital stay, lung function, oxygenation, bacterial load, symptom scores, QoL, exercise tolerance, time to relapse.
Notes
*Risk of bias*
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	High risk	Done sequentially upon admission.
Allocation concealment (selection bias)	High risk	Allocation was sequential.
Blinding of participants and personnel (performance bias)   All outcomes	Low risk	Taste of intervention and control masked by quinine.
Blinding of outcome assessment (detection bias)   All outcomes	Low risk	Investigators blinded to intervention.
Incomplete outcome data (attrition bias)   All outcomes	Low risk	No drop outs.
Selective reporting (reporting bias)	Low risk	All outcomes reported.
Other bias	Low risk	None apparent.

Methods	Randomised, double‐blind trial. Design: parallel. Location: 16 adult or paediatric hospitals in Australia. Duration: 48‐weeks. The trial was conducted between September 2000 and November 2003.
Participants	Total participants: n = 164, 93 males and 71 females. Age: over 6 years. HS Group (n = 83) Mean (SD) age: 18.4 (9.3) years. Gender split: females 46%. BMI mean (SD): 19.9 (3.9). Lung function (mean (SD)) FEV₁: 73 (21) range (40 – 132) FVC: 85 (18) range (45 ‐ 127) FEF25‐75: 56 (34) range (11 ‐ 155) Sputum: Pseudomonas aeruginosa: 79%; Staphylococcus aureus: 44%. Control Group (n = 81) Mean (SD) age: 18.7 (9.2) years Gender split: females 42% BMI mean (SD): 20.1 (3.6) Lung function (mean (SD)) FEV₁: 76(21), range (40 – 127) FVC: 88 (18) range (44 ‐ 137) FEF_25‐75: 61 (35) range (10 ‐ 151) Sputum: Pseudomonas aeruginosa: 78%; Staphylococcus aureus: 47%.
Interventions	Group 1: 4 mL HS 7% 2x daily. Group 2: 4 mL IS 0.09% 2x daily. Solutions were prepared by Pfizer, quinine sulphate (0.25 mg per mL) was added as a taste‐masking agent.  Solutions were nebulized with a Pari LC PLUS jet nebulizer and a Pari Proneb Turbo compressor. A bronchodilator was administered before each inhalation of the trial solution. All other standard care was maintained throughout the trial.
Outcomes	Mean change in FEV₁ and FVC at 4, 12, 36 and 48 weeks. QOL and pulmonary exacerbations.
Notes	Sample size calculation undertaken.
*Risk of bias*
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Concealed computer randomisation with minimisation algorithm to balance for age, FEV₁ and long‐term treatment with rhDNase, use of physiotherapy and trial centre.
Allocation concealment (selection bias)	Low risk	Randomisation performed by a person not otherwise involved in the trial.
Blinding of participants and personnel (performance bias)   All outcomes	Low risk	Double blind, participant blinding was achieved by masking the taste of the solutions with quinine sulphate. Participants and their clinicians, remained unaware of the treatment assignments throughout the trial.
Blinding of outcome assessment (detection bias)   All outcomes	Low risk	The research assistants and the trial coordinator remained unaware of the treatment assignments throughout the trial.
Incomplete outcome data (attrition bias)   All outcomes	Low risk	2 participants (1 from each group) withdrew voluntarily after randomisation and before first dose. 82 in HS group and 80 in control group included in ITT analysis. Withdrawals described as follows: HS Group: 15 in total withdrawn: 7 lost to follow‐up (2 owing to time constraints; 2 owing to insufficient perceived benefit from trial solution; 2 owing to adverse reaction to trial solution (cough); 1 provided no reason) and 8 stopped inhalations but continued visits (4 had adverse reaction to trial solution; 1 had cough and vomiting; 1 had pharyngitis and wheezing; 1 had voice changes; 1 had chest tightness; 2 could not tolerate taste of trial solution; 1 had insufficient benefit from trial solution; 1 lost interest). Control Group: 17 in total withdrawn: 10 Lost to follow‐up (5 owing to time constraints; 3 owing to insufficient perceived benefit from trial solution; 1 failed to attend; 1 provided no reason) and 7 stopped inhalations but continued visits (3 owing to time constraints; 2 had adverse reaction to trial solution (tonsillitis in 1 and lethargy in 1); 1 had insufficient benefit from trial solution; 1 provided no reason.
Selective reporting (reporting bias)	Low risk	All outcomes stated in the methods were described in the results.
Other bias	Low risk	Sample size calculation undertaken, no other potential bias identified.

Methods	Open‐label, randomised trial. Design: parallel. Duration: 2 weeks. Location: 2 centres in Australia (one children's hospital and one adult unit).
Participants	Total participants: n = 58 randomised, 6 withdrew during trial. Inclusion criteria  Diagnosis of CF with positive sweat chloride test.  Able to do pulmonary function tests.  Cough and daily sputum production.  Regular chest physiotherapy at home.  Reasonable distance from clinic.  On stable medications regime for last 14 days. Exclusion criteria  > 20% fall in FEV₁ at baseline assessment.  Exacerbation of CF in last 4 weeks requiring admission to hospital.  Exacerbation requiring admission to hospital during trial period. HS Group (n = 27).  Gender split: 18 males, 9 females.  Mean (range) age: 16.1 (7 to 25) years. Height (mean (SD)): 155 (17.7) cm. Weight (mean (SD)): 47 (14.5) kg. FEV₁ % predicted (mean (SD)): 50.0 (9.7). FVC % predicted (mean (SD)): 73.5 (15.9). IS Group (n = 25).  Gender split: 13 males, 12 females. Mean (range) age: 16.7 (8 to 36) years. Height (mean (SD)): 150 (19.6) cm. Weight (mean (SD)): 43 (16.2) kg. FEV₁ % predicted (mean (SD)): 53.7 (7.8). FVC % predicted (mean (SD)):77.2 (9.8).
Interventions	Pre‐treated salbutamol 600 mcg MDI and volumatic spacer device.  Group 1: 10 mL HS 6% 2x daily. Group 2: 10 mL IS 2x daily. Inhaled using ultrasonic nebuliser (Omron NE‐U 07). First and last inhalations administered in clinic under a doctor's supervision.
Outcomes	Mean change in FEV₁ at 2 weeks; mean change FVC at 2 weeks; VAS for cleared chest at 1 and 2 weeks; VAS for dyspnoea, fatigue, appetite, exercise tolerance, quality of sleep, general well‐being; adverse effects (increased cough, haemoptysis, chest tightness and pharyngitis).
Notes	Sample size calculation undertaken.
*Risk of bias*
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Random number tables used.
Allocation concealment (selection bias)	Unclear risk	No detail provided.
Blinding of participants and personnel (performance bias)   All outcomes	High risk	Open label, participants not told which group they were in, but not able to disguise trial drug due to salty taste.
Blinding of outcome assessment (detection bias)   All outcomes	Low risk	Technician measuring lung function was blinded to treatment assignment.
Incomplete outcome data (attrition bias)   All outcomes	Low risk	6 participants withdrew in total (3 from each group) due to: non‐compliance with clinic visit (1 in IS group); exacerbation of respiratory infection requiring hospital admission (2 IS group, 1 HS group); irritating cough during inhalation (1 HS group); increased haemoptysis which occurred 3 hours after first treatment (1 HS group). No specific mention of whether an ITT analysis had been performed.
Selective reporting (reporting bias)	Low risk	All outcomes stated in the methods were described in the results.
Other bias	Low risk	Sample size calculation undertaken, no other bias identified.

Methods	Randomised double‐blind trial. Design: cross‐over. Duration: single dose of each treatment, washout period not stated. Location: USA (single centre).
Participants	Total participants: n = 12. Age: median (range) 10.5 (8.9 ‐ 12.4) years, 5 males. Normal pulmonary function (FEV₁ and FVC > 90% of predicted values).
Interventions	Group 1: HS 7%. Group 2: 0.12% saline. Treatment followed by radio‐labelled isotopes.
Outcomes	Mucociliary clearance at 20, 60 and 90 minutes and 24 hours.
Notes	Mearsurements of MMC following inhalation of 0.12% saline were compared to 9 healthy adult controls. Abstract only. No sample size calculation stated.
*Risk of bias*
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	The method of randomisation is not stated.
Allocation concealment (selection bias)	Unclear risk	Not stated in methods.
Blinding of participants and personnel (performance bias)   All outcomes	High risk	No attempt was made to blind to taste of the solution.
Blinding of outcome assessment (detection bias)   All outcomes	Unclear risk	Not stated in methods.
Incomplete outcome data (attrition bias)   All outcomes	Low risk	Low risk as dropouts were replaced.
Selective reporting (reporting bias)	Low risk	All reported outcomes were given.
Other bias	Low risk	Sample size was estimated from data based on adolescents

Methods	Double‐blind randomised controlled trial. Design: cross‐over design. Duration: 1st arm of 28 days followed by a 28‐day washout period and then alternative treatment for 28 days. Location: multicentre in Germany.
Participants	69 people with CF.
Interventions	Group 1: HS 6% via PariSinus^TM. Group 2: IS via PariSinus^TM.
Outcomes	Primary outcome: Sinonasal outcome test (SNOT‐20) upper airway symptoms/disease‐specific QoL. Secondary outcomes: rhinoscopy, rhinomanometry, cytokines in nasal lavage.
Notes
*Risk of bias*
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Stated but not defined.
Allocation concealment (selection bias)	Unclear risk	This was stated but not described.
Blinding of participants and personnel (performance bias)   All outcomes	High risk	No attempt was made to blind the hypertonic saline solution taste.
Blinding of outcome assessment (detection bias)   All outcomes	Unclear risk	Stated but not described in detail.
Incomplete outcome data (attrition bias)   All outcomes	Low risk	All drop outs clearly defined.
Selective reporting (reporting bias)	Low risk	All outcomes that were stated were described.
Other bias	Low risk	No other major source of bias detected.

Methods	Randomised controlled trial. Design: 4‐way cross‐over trial (no information on any washout period). Duration: single day for each intervention. Participants were initially randomised to receive either the mannitol or HS. On the second day they were randomised to either the remaining active or the control for the first day. On the third day they were randomised to receive either the remaining active or either of the controls. The final day was the remaining control. Location: Australia.
Participants	Total participants: n = 12, 5 males and 7 females.  Age mean (SD) (range): 29.9 (9.4) (16 ‐ 46) years. BMI mean (SD) (range): 21.0.(1.8) (18 ‐ 24). 10/12 participants were colonised with Pseudomonas aeruginosa, 7/12 had Stapylocococcus aureus (including the 2 participants without Pseudomonas aeruginosa) and 4/12 had Aspergillus fumigatus.
Interventions	Pre‐treated with terbutaline 1000 mcg (turbulhaler).  Group 1: single dose 7 mL HS 6%.  Group 2: IS (0.9%) plus matched voluntary cough.  Group 3: mannitol 300 mg (encapsulated dry powder).  Group 4: empty capsules with matched voluntary coughs.
Outcomes	Sputum isotope % clearance at 30 minutes, sputum isotope clearance at 90 minutes, mucociliary clearance.
Notes	Isotope clearance was reported in this paper as occurring at 60 minutes. This is actually the same time period as the 90‐minute clearance reported in 1997 paper. The terminology had been changed. Lung function data are the mean values for all trial days: FEV₁ % predicted mean (SD) (range): 60.2.(16.5) (42 ‐ 87). FVC % predicted mean (SD) (range): 78.8.(16.5) (47 ‐ 102). FEF_25‐75 % predicted mean (SD) (range): 32.5.(21.1) (11 ‐ 77). No sample size calculation stated.
*Risk of bias*
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	No detail provided.
Allocation concealment (selection bias)	Unclear risk	The allocation concealment process was not described.
Blinding of participants and personnel (performance bias)   All outcomes	High risk	Participants could discern taste.
Blinding of outcome assessment (detection bias)   All outcomes	Low risk	The trials were coded such that the investigators were blinded to the identity of the intervention at the time of data analysis.
Incomplete outcome data (attrition bias)   All outcomes	Unclear risk	No discussion of whether an ITT analysis had been used or of any withdrawals.
Selective reporting (reporting bias)	Low risk	All outcomes stated in the methods were described in the results.
Other bias	Unclear risk	Washout period not clear. No sample size calculation stated. The time course of the effect of the interventions on the outcomes is not clear.

Methods	Prospective open‐label randomised controlled trial. Design: cross‐over with 3 treatment arms. 48 children were randomised, 8 to each of the 6 possible treatment orders. Duration: each arm lasted 12 weeks with a 2‐week washout period between treatments. Location: multicentre in UK (2 institutions).
Participants	Total participants recruited: n = 48, but 1 withdrew without commencing treatment, so trial population is 47.  Age (mean (SD)): 12.6 (2.8) years, range (7.3 ‐ 17 years). Gender split: 19 (40%) males; 28 (60%) females. Weight (mean (SD)): 40·0 (12·6) kg, range (18·8 ‐ 77). Spirometry: FEV₁ (L) (mean (SD)): 1·18 (0·47), range (0·44 ‐ 2·34); FEV₁ (% predicted) (mean (SD)): 48% (15), range (14 ‐ 77); FVC (% predicted) (mean (SD)): 68% (22), range (20 ‐ 112). Lung microbiology (number of children with 3 positive cultures of the organism in the previous year): Pseudomonas aeruginosa: 22 (48%); Staphylococcus aureus: 18 (39%); Stenotrophomonas maltophilia: 1 (2%).
Interventions	Pre‐treated with bronchodilators. All treatments were administered with a Sidestream nebuliser and Porta‐Neb compressor (Medic‐Aid, Bognor Regis, UK). Group 1: 5 mL HS 7% 2x daily immediately before the participant's regular physiotherapy session. Group 2: rhDNase 2.5 mg 1x daily at least 1 hour before physiotherapy. Group 3: 2.5 mg alternate daily at least 1 hour before physiotherapy. Routine medication and physiotherapy were continued throughout the trial.
Outcomes	Primary outcome: % change in FEV₁ from baseline. Secondary outcomes: FVC; number of pulmonary exacerbations (defined as a previously outlined protocol for respiratory‐tract infections); weight gain; exercise tolerance (3‐min step test and oxygen saturation monitored); QoL (quality of well‐being scale self‐administered form 1·04, filled out by the participant and guardian together); total health‐care cost (hospital and community‐health‐service perspective, so participants' costs excluded from analysis; resources included covered hospital admissions (inpatient, outpatient, and day case), radiological investigations, blood tests, drug use, and the use of community services (visits to general practitioners, district nurses, and physiotherapists)); adherence (count of unused bottles of HS and empty vials of rhDNase; each participant was also given a diary to record the treatment doses taken).
Notes	Sample size calculation undertaken. Before starting the hypertonic‐saline treatment period, each participant received a test dose of HS in hospital so that he or she could be monitored for bronchoconstriction.
*Risk of bias*
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Telephone randomisation to an independent trials coordinating unit, stratified by hospital and balanced after each group of 12 children.
Allocation concealment (selection bias)	Low risk	Telephone randomisation to an independent trials coordinating unit,
Blinding of participants and personnel (performance bias)   All outcomes	High risk	No attempt to conceal taste, paper states masking impossible because HS can easily be distinguished from rhDNase by its salty taste and timing in relation to physiotherapy.
Blinding of outcome assessment (detection bias)   All outcomes	Unclear risk	No statement on blinding of outcome assessors.
Incomplete outcome data (attrition bias)   All outcomes	Unclear risk	An ITT approach was used within this trial, 43 children are included in the comparison of daily and alternate‐day rhDNase, and 40 in the comparison of daily rhDNase and hypertonic saline. Details of withdrawals as follows: 1 girl withdrew almost immediately after randomisation without starting the first treatment due to illness; 8 children were unable to complete all 3 treatment periods; 4 participants had severe declines in their pulmonary status and required long courses of intravenous antibiotics (2 of them were taking alternate‐day rhDNase, 1 HS, and the other daily rhDNase). In the additional report of airway inflammatory changes following treatment, only 28 of the 48 participants were able to perform induced sputum and be included. It is not evident that any attempts were made to adjust for missing data from those participants unable to do induced sputum.
Selective reporting (reporting bias)	Low risk	All outcomes stated in the methods were described in the results.
Other bias	Low risk	We judged a 2‐week washout period to be low risk. Sample size calculation undertaken.

Study	Reason for exclusion
Brivio 2016	Comparison of HS to HS plus HA (no control without HS).
Buonpensiero 2010	Comparison of HS to HS plus HA (no control without HS)
DeCono 2008	Not randomised.
Dentice 2012	Did not compare HS to a control group. Instead the trial sought out the optimum timing of physiotherapy to HS use, before, during or after.
Donaldson 2006	Did not compare to a control group that did not include HS, comparison of HS with or without pre‐treatment with amiloride.
Elkins 2006b	Comparison of dose frequency of HS; all participants received HS, but randomised to 2 or 4 times daily.
EUCTR2007‐002707‐40‐BE	Not randomised.
Genkova 1998	Did not compare to a control treatment; did not report any results.
Grasemann 2013	The trial did not include an arm with HS. It compared inhaled L‐arginine with isotonic saline as a control.
IRCT20180307038994N1	Not randomised.
King 1997	In vitro trial only.
Kobylyansky 2000	Trial was not performed in a CF population.
NCT01094704	Not randomised; reporting results at different time points after a single dose of HS.
O'Neill 2017	Comparison of timing of HS in reference to airway clearance. No comparator group that did not include HS.
Ros 2012	Comparison of 2 formulations of 7% HS, with or without HA.
San Miguel 2016	Comparison of 2 arms both using HS with and without physiotherapy interventions.
Van Ginderdeuren 2008	Did not compare HS to a control group. Instead the trial sought to evaluate the efficacy of an autogenic drainage treatment combined with HS.
Van Ginderdeuren 2011	Did not compare HS to a control group. Instead the trial sought to evaluate the efficacy of an autogenic drainage treatment combined with HS.
Vanlaethem 2008	Comparison of HS in conjunction with airway clearance techniques.

Methods	RCT. Cross‐over design (1‐week washout between treatments). Duration: single inhalation of each treatment. Multicentre (2 centres) in Canada. Concealed, computer‐generated randomisation performed by a research pharmacist not otherwise involved in the study; clinicians and research personnel remained unaware of the treatment assignments throughout the study, including the primary efficacy analysis. The solutions were indistinguishable from each other in appearance, but not in taste. Sample size calculation was undertaken.
Participants	Inclusion criteria: confirmed diagnosis of CF; informed consent and verbal assent (as appropriate); at least 6 years of age at enrolment; able to perform reproducible spirometry meeting American Thoracic Society standards; pre‐bronchodilator FEV₁% predicted ≥ 40% predicted; able to perform reproducible LCI maneuvers at screening. Exclusion criteria: airway cultures yielding Burkholderia cepacia complex in the previous 2 years or non‐tuberculous mycobacteria in the past year; oral corticosteroid use; oxygen supplementation; lung transplantation; intravenous antibiotics or oral quinolones within 14 days of enrolment; or investigational drugs within 30 days of enrolment. Participants who experienced a drop in FEV₁ of 20% or more after study drug administration were also excluded from further study participation. 242 people with CF identified for the study (134 from St Michael's Hospital and 108 from the Hospital for Sick Children). 113 (47%) were excluded because they were currently using HS. 129 were approached of which 21 (16%) people consented and were enrolled in the trial. 21 participants randomised; 16 completed all of the time point measurements; 18 participants contributed to the intention‐to‐treat analysis and 3 participants were excluded. Age median (range): 140 (7 ‐ 56) months. Gender n (%): 11 (61.1%) females. LCI median (range): 122 (6.5 ‐ 21.1). FEV₁% predicted median (range): 86.9 (47.4 ‐ 102.8). FVC % predicted median (range): 97.9 (61.9 ‐ 121.8). FEF25‐75% predicted median (range): 67.1 (19.5 ‐ 99.2). Delta F508 homozygous n (%): 16 (88.9%). Pseudomonas aeruginosa positive sputum culture n (%): 17 (94.4%).
Interventions	Intervention: single inhalation of 4 mL HS (7%). Control: single inhalation of 4 mL IS (0.9%). The solutions were administered using the PARI LC Star nebuliser (Pari, Midlothian, Virginia, USA). 2x 100 ug puffs of salbutamol were administered before each inhalation of study solution using a holding chamber (Aerochamber Max, Trudell, London, Canada).
Outcomes	MBW and spirometry were performed at each visit ‐ at baseline, 1, 2, 4 and 24 h post inhalation. Primary outcome LCI change from baseline to 24 h post inhalation. Secondary outcomes LCI SF6 change from baseline to 24 h post inhalation. Spirometry (FEV₁, FEF25‐75) change from baseline to 24 h post inhalation. Changes in LCIN2, LCISF6 and spirometric outcomes over 24 h (i.e. slope analysis of all time points). Adverse events.
Notes	All tests were performed in the research pulmonary function laboratory at the Hospital for Sick Children, Toronto Canada between April 2012 and September 2014. The trial was stopped because of difficulty with recruitment. Dr. Felix Ratjen has acted as a consultant for Novartis Pharmaceuticals. Funding support as well as the hypertonic saline used in the study was provided by Novartis Pharmaceuticals.

PERMALINK

Nebulised hypertonic saline for cystic fibrosis

Peter Wark

Vanessa M McDonald

Abstract

Background

Objectives

Search methods

Selection criteria

Data collection and analysis

Main results

Authors' conclusions

Plain language summary

Summary of findings

Background

Description of the condition

Description of the intervention

How the intervention might work

Why it is important to do this review

Objectives

Methods

Criteria for considering studies for this review

Types of studies

Types of participants

Types of interventions

Types of outcome measures

Primary outcomes

Secondary outcomes

Search methods for identification of studies

Electronic searches

Searching other resources

Data collection and analysis

Selection of studies

Data extraction and management

Assessment of risk of bias in included studies

Measures of treatment effect

Unit of analysis issues

Dealing with missing data

Assessment of heterogeneity

Assessment of reporting biases

Data synthesis

Subgroup analysis and investigation of heterogeneity

Sensitivity analysis

Summary of findings and quality of the evidence

Summary of findings for the main comparison. Hypertonic saline 3% to 7% versus isotonic saline for cystic fibrosis (stable lung disease).

Summary of findings 2. Hypertonic saline 3% to 7% versus isotonic saline for cystic fibrosis (during acute exacerbations of lung disease).

Summary of findings 3. Hypertonic saline compared with rhDNase with for cystic fibrosis.

Summary of findings 4. Hypertonic saline compared with amiloride for cystic fibrosis.

Summary of findings 5. Hypertonic saline compared with sodium‐2‐mercaptoethane sulphonate (Mistabron®) for cystic fibrosis.

Summary of findings 6. Hypertonic saline compared with mannitol for cystic fibrosis.

Results

Description of studies

Results of the search

Included studies

Trial design

Participants

Selection by tolerance for hypertonic saline

Baseline microbiology

P aeruginosa

S aureus

Other pathogens

Interventions

Outcomes

Excluded studies

Studies awaiting classification

Ongoing studies

Risk of bias in included studies

1.

Allocation

Generation of the randomisation sequence

Allocation concealment

Blinding

Incomplete outcome data

Selective reporting

Other potential sources of bias

Effects of interventions

Hypertonic saline 3% to 7% versus isotonic saline in stable lung disease

Primary outcomes

1. Lung function

a. FEV1

a. FEV₁

d. Change in FEV_0.5

a. FEV₁

Methods	Prospective, randomised, double‐blind controlled trial. Duration: 1 year.
Participants	Children over 6 years of age with a diagnosis of CF made by 6 months of age. 19 participants randomised: 3 excluded, 9 participants in HS group, 7 participants in IS group.
Interventions	Intervention: HS 3% plus 0.25 mg/kg salbutamol 2x daily. Control: IS 0.9% plus 0.25 mg/kg salbutamol 2x daily.
Outcomes	Primary outcome: maximal flow at functional residual capacity (change from baseline). Secondary outcomes: pulmonary exacerbations, respiratory rate, nutritional status, adverse events.
Notes

Methods	Controlled trial ‐ randomisation not clear.
Participants	Children with CF under 6 years.
Interventions	Intervention: single inhalation of HS 7%. Control: single inhalation of IS 0.9%.
Outcomes	Change in LCI.
Notes	To study the feasibility of using lung clearance index to assess treatment effect outcomes in CF trials, especially in children under 6 years. We are waiting for further data to judge whether this should be included.

Methods	RCT. Cross‐over design with washout period (participants "discontinued use of HS for 72 h prior to each study visit"). Duration: 2 overnight visits, 1 for each treatment arm Location: USA.
Participants	Inclusion criteria: adults with CF with FEV₁ 40% ‐110% of predicted and a BMI < 30kg/m². Exclusion criteria: currently experiencing an acute upper or lower respiratory tract infection or requiring treatment with antibiotics or systemic corticosteroids within 28 days of enrolment (not including normal maintenance antibiotics), diagnosis of sleep apnoea, symptoms of allergic rhinitis, previous diagnosis of Burkholderia cepacia, smokers, or pregnant or nursing. All participants performed a 30 min tolerance test of pulmosal inhalation from the tPAD device prior to the overnight visits and were excluded if they demonstrated a > 10% reduction from pre‐dose value in FEV₁, measured 30 min after completion. 12 participants included. Age, mean (SD): 31.8 (9.7) years. Gender: 8 males, 4 females.
Interventions	Participants discontinued use of HS for 72 h prior to each visit. Long‐acting beta agonists were halted for 12 h and short‐acting beta agonists for 6 h prior. Inhaled antibiotics were allowed prior to, or after tPAD use. The tPAD device includes a 2 LPM air pump, an Aeroneb ProNebulizer (Aerogen,Galway, Ireland), a 250 mL liquid reservoir, a liquid collection chamber, and an integrated nebulization chamber where the aerosol is combined with the flow from the air pump. It also includes electronics allowing for timed device operation for up to 8 h. A system‐specific nasal cannula is attached to the integrated nebulization chamber and used to deliver the aerosol. For this trial the cannula was secured to the participant using a Wisp nasal mask frame and headgear (Philips Respironics, Murraysville, PA). Overnight HS visit: inhaled HS* from the tPAD device from 11:30 pm to 7:30 am in the clinical research unit; the tPAD was loaded with an initial HS dose of 240 mL and reloaded 5.5 h later with 60 ‐ 80mL of HS. Overnight sham visit: participants wore the cannula as they did during the HS visit and the tPAD was powered on, but the nebuliser and the air pump were non‐operational and no air flowed through the cannula. * Pulmosal 7% (pH+) sodium chloride inhalation solution was used for all trials except 1 where it was not available. Pulmosal is sterile, non‐pyrogenic, preservative‐free, and balanced to a pH of 7.4. In participant 9 another 7% HS product for inhalation was used.
Outcomes	Primary outcome: MCC. Secondary outcomes: safety assessments, absorptive clearance, and change from baseline in Sino‐Nasal Symptoms (SNOT‐14) and modified Leeds Sleep Evaluation Questionnaires (mLSEQ). Pulse oximetry was monitored throughout the night while the participants slept and the tPAD operated continuously.
Notes	Participants who did not complete both nights were not included in the analysis and were replaced until a total of 12 participants had completed both visits.

Methods	RCT. Location: USA. Duration: 4 weeks.
Participants	Children with CF and stable lung disease (FEV₁ > 60%) aged between 5 and 18 years. 24 screened, 23 randomised, 20 completed treatment and follow‐up.
Interventions	Intervention: HS 6% 3x daily via eFlow nebuliser. Control: IS 0.12% 3x daily via eFlow nebuliser.
Outcomes	Primary outcome Mucociliary clearance. Secondary outcomes Spirometry. QoL (CFQ‐R).
Notes	We are waiting for further data to judge whether this trial should be included.

Methods	RCT. Parallel design. Duration: 16 weeks. Location: Australia. Sequence generation: random number generation with block allocation. Treatment allocation is stratified for: age, gender, FEV₁. Allocation concealment: random allocation to 1 of 3 groups by the Trial Pharmacist at the trial co‐ordinating centre. Treatment allocation recorded at the Trial Pharmacy and the random allocation lists, randomisation procedure and the unblinded treatment allocation is to be concealed from all other trial staff and the participant. Blinded.
Participants	Inclusion criteria: informed consent, diagnosis of CF (positive sweat test or genotyping), best FEV₁ in the previous six months > 20% of predicted normal value FEV₁ > 85% of best in the previous 6 months, no non‐routine antibiotics in the last 14 days, minimum age 6 years, both genders eligible. Exclusion criteria: colonisation with Burkholderia cepacia, major haemoptysis within the last 12 months, pregnant or lactating females, investigational drugs within the last 30 days, previous lung transplant, hypertonic saline within the last 14 days, inhaled mannitol within the last 14 days.
Interventions	Intervention 1: 2x daily inhalation of 4 mL of nebulised 6% HS + 0.25 mg/mL quinine sulphate. Intervention 2: 2x daily inhalation of 4 mL of nebulised 3% HS + 0.25 mg/mL quinine sulphate. Control: 2x daily inhalation of 4 mL of nebulised 0.9% IS + 0.25mg/mL quinine sulphate.
Outcomes	Primary outcome Lung function as measured by the change in FEV₁ % predicted (measured at baseline, Week 1, Week 4, Week 8 and Week 16 (end of trial)). Secondary outcomes Lung function as measured by the change in FVC % predicted (measured at baseline, Week 1, Week 4, Week 8 and Week 16 (end of trial)). Lung function as measured by the change in FEF25‐75 % predicted (measured at baseline, Week 1, Week 4, Week 8 and Week 16 (end of trial)). QoL as measured by the Cystic Fibrosis Questionnaire‐Revised (CFQ‐R) (measured at baseline, Week 1, Week 4, Week 8 and Week 16 (end of trial)). QoL as measured by the Medical Outcomes Survey Short Form‐36 (SF‐36) (measured at baseline, Week 1, Week 4, Week 8 and Week 16 (end of trial)). Exercise capacity as measured by the total distance covered in the Modified Shuttle Test‐25 (MST‐25) (measured at baseline, Week 4 and Week 16 (end of trial)) Exercise capacity as measured by the total exercise time in the Endurance Shuttle Test‐25 (EST‐25) (measured at baseline, Week 4 and Week 16 (end of trial)). Sputum bacterial diversity as measured by the acquisition or loss of bacterial organisms in expectorated sputum as measured by routine microscopy culture and sensitivity (M/C/S) (measured at baseline and Week 16 (end of trial)). Tolerability of nebulised trial solution as measured by participant on a 10‐point visual analogue scale (measured at baseline, Week 1, Week 4, Week 8 and Week 16 (end of trial)). Medication use as measured by number of doses of each prescribed medication (measured at baseline and weekly during trial (Week 1 to Week 16)). Pulmonary exacerbations as measured by the Fuchs exacerbation criteria (measured weekly during trial (Week 1 to Week 16)). Adverse events (such as intolerable cough, sore throat, bronchospasm, haemoptysis, nausea, pulmonary exacerbation) as measured by presence of new symptoms, likelihood of being related to trial solution, severity of symptoms and time to resolution of symptoms (measured weekly during trial (Week 1 to Week 16)). Adherence to nebulisation of trial solution as measured weekly by self‐report in patient diary and count of returned unused ampoules of trial solution at the end of the trial (week 16) Administration time of nebulised trial solution as measured by stop watch from start to completion of 1 dose of trial inhalation solution (measured at baseline, Week 1, Week 4, Week 8 and Week 16 (end of trial)).
Notes	Saline at lower tonicity in cystic fibrosis (SALTI‐CF) trial. Funding source: Australian Cystic Fibrosis Research Trust.

Methods	Open label RCT. Single dose.
Participants	20 adults with CF.
Interventions	Intervention: amiloride in HS 5.58%. Control: amiloride in IS.
Outcomes	Change in nasal potential difference.
Notes	Trial to determine the effects of HS and amiloride on change in ion flow by nasal potential difference. Abstract only.

Methods	RCT. Parallel design. Duration; 14 days. Triple‐blind (participant, care provider, investigator).
Participants	Estimated enrolment: 60 participants. Both genders eligible. Inclusion criteria: diagnosed with CF (medical record evidence of CFTR mutation or sweat chloride test or nasal voltage difference, and 1 or more clinical findings of CF); 12 years or older; FEV₁ > 30% predicted (within the last 14 days and oxygen saturation > 90% on FiO2 ≤ 50%); admitted for an exacerbation; use of effective contraception in women; written informed consent. Exclusion criteria: pregnancy; history of asthma based on methacholine challenge or bronchial hyper‐responsiveness on PFT; haemoptysis more than 60 mL within the last 30 days; use of any investigational study drug within the last 30 days; initiation of hypertonic saline within the last 30 days; a serum creatinine 2 mg/dL or more; active malignancy in the last year; antibiotics for CF exacerbation as an outpatient in the last 2 weeks; Burkholderia cepacia colonisation; waiting list for lung transplant; lack of FEV₁ data from the last 14 days; previous participation in this study.
Interventions	Intervention: aerosolized 7% HS (5 mL) 2x daily. Control: 15% xylitol (5 mL) 2x daily.
Outcomes	Primary outcomes FEV₁ (change from baseline). Adverse events. Respiratory symptom score. Secondary outcomes Density of colonisation per g of sputum. Time to next exacerbation. Sputum cytokines. CFQ‐R.
Notes	Principal Investigator: Joseph Zabner, M.D. Study Director: Lakshmi Durairaj, M.D. Study Chair: Jan L Launspach, R.N., CCRC. Study Start Date : June 2009. Estimated Primary Completion Date : January 2018. Estimated Study Completion Date : January 2018.

Methods	Randomised, cross‐over trial. Open label. Duration: 2 weeks.
Participants	Estimated enrolment: n = 30 (stated that recruitment complete). Inclusion criteria: documented diagnosis of CF (medical record evidence of 2 identified CFTR mutations or a positive sweat chloride test or nasal voltage difference, and 1 or more clinical findings of CF); 16 years or older; FEV₁ over 30% predicted; oxygen saturation at least 90% on room air; clinically stable, without evidence of pulmonary exacerbation for at least 2 weeks prior to screening (defined as use of oral or intravenous antibiotics for CF exacerbation); use of effective contraception in women; ability to provide written informed consent and assent; successful completion of the trial doses of study drugs. Exclusion criteria: pregnancy; haemoptysis more than 100 mL within the last 30 days; change in chronic medication within the last 30 days; history of elevated serum creatinine (at least 2 mg/dL) within 30 days or at screening; history of lung and other solid organ transplantation; wait‐listed for lung or other solid organ transplant; known intolerance to inhaled HS.
Interventions	Intervention 1: aerosolised xylitol (5 mL) 2x daily for 14 days. Intervention 2: aerosolised 7% HS (4 mL) 2x daily for 14 days.
Outcomes	Primary outcomes: FEV₁ change from baseline; adverse events; and respiratory symptom score. Secondary outcomes: density of colonisation per gram of sputum; time to next exacerbation; sputum cytokines; and CFQ‐R. All outcomes measured at 98 days.
Notes	Sponsored by University of Iowa. Collaborators: Ann & Robert H Lurie Children's Hospital of Chicago Northwestern University. U01HL102288 (US NIH Grant/Contract).

Methods	Open‐label RCT. Parallel design. Duration: 48 weeks. Multicentre (3 centres) in Madrid, Spain.
Participants	Actual enrolment : 71 participants. Inclusion criteria: clinical diagnosis of CF; over 6 years old; FEV₁ over 30% predicted; able to perform spirometry; able to perform induced sputum; able to tolerate the maximum dose of 10 mL HS; no oral or intravenous treatment within the previous 2 weeks before the beginning of the study; no treatment with HS in the 2 weeks before study entry. Exclusion criteria: no clinical diagnosis of CF; not able to tolerate 10 mL HS; positive pregnancy test; not able to tolerate beta 2‐agonist; treatment with corticosteroids; FEV₁ < 30% predicted; liver or lung transplantation, or both; oxygen treatment; hospital admission within the 4 previous weeks; oral or intravenous antibiotic treatment within the 2 previous weeks; smokers; pulmonary colonisation with Burkholderia cepacia complex.
Interventions	Intervention: 10 mL HS. Control: 5 mL HS.
Outcomes	Primary outcomes Time free from pulmonary exacerbation (days) at 12 months. Secondary outcomes Changes in lung function at 12 months. Changes in inflammatory markers in induced sputum at 12 months. QoL at 12 months (CFQ‐R).
Notes	Principal Investigator: Dr Adelaida Lamas, Cystic Fibrosis Unit. Ramón y Cajal University Hospital, Madrid, Spain. Study Start Date : March 2009. Primary Completion Date : May 2011. Study Completion Date : September 2012.

Methods	Blinded (participant, care provider, investigator, outcomes assessor) RCT. Parallel design. Duration: 1 year. Multicentre in Germany.
Participants	Actual enrolment : 42 participants. Inclusion criteria: confirmed diagnosis of CF; age at enrolment is 0 ‐ 4 months; ability of child and parents to comply with medication use, trial visits, and trial procedures as judged by the investigator; written consent from participants' parents or legal guardians. Exclusion criteria: born < 30 weeks gestation; prolonged mechanical ventilation in the first 3 months of life; significant medical disease or condition other than CF likely to interfere with the child's ability to complete the entire protocol; previous major surgery except for meconium ileus; other major organ dysfunction, excluding pancreatic or hepatic dysfunction or another condition due to CF; physical findings that would compromise the safety of the participant or the quality of the study data as determined by investigator; history of adverse reaction to sedation; known hypersensitivity to study treatment; participation in other interventional studies at the same time.
Interventions	Intervention: 6% HS 4 mL inhaled 2x daily. Control: 0.9% IS 4 mL inhaled 2x daily. Both treatments inhaled via PARI LC SPRINT® Junior nebulizer with a baby bend, size‐adapted PARI® Baby face mask size 0 ‐ 3, connection tubing (2.2m) and a PARI JuniorBOY® SX compressor.
Outcomes	Primary outcomes Number of participants with AEs and serious AEs. Safety of inhalation with HS and IS in newborns and infants with CF assessed by proportion of AEs and serious AEs.    Secondary outcomes Protocol‐defined pulmonary exacerbations requiring treatment with oral, inhaled or intravenous antibiotics.  Morphological or functional changes (or both) due to CF lung disease according to MRI chest score and chest x‐ray. Chrispin‐Norman score. Extent and severity of bronchial dilatation after MRI and chest x‐ray scores. Impairments in lung function determined via multiple breath washout.  Severity of impairment in lung function test.  Health‐related QoL (as assessed by CFQ‐R, German version).  Change in anthropometric and basic respiratory parameters (weight, height, BMI, weight‐for‐height, resting respiratory rate, and room air oxygen saturation).  New isolates of CF pathogens from clinically collected respiratory cultures.  Time to first isolation of a CF pathogen.
Notes	Sponsors and Collaborators: Heidelberg University, German Center for Lung Research. Principal Investigator: Marcus A Mall, MD University Hospital Heidelberg. Study Start Date : June 2012. Primary Completion Date : November 2016. Study Completion Date : October 2017.