Summary of findings 3. Hypertonic saline compared with rhDNase with for cystic fibrosis.
| Hypertonic saline compared with rhDNase with for cystic fibrosis | ||||||
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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 | |||||
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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 low3,4,5 | 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. |
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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 low2,6,7 | 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). |
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| LCI | Outcome not reported. | NA | NA | NA | ||
| Mortality | Outcome not reported. | NA | NA | NA | ||
| Measures of sputum clearance | Outcome not reported. | NA | NA | NA | ||
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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 low2,6,7 | 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. |
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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 low2,6,7 | 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. | ||||||
1. An alternate day rhDNase group was also included in one of the trials (Suri 2001), but to allow a comparison across the trials, only results from the rhDNase daily group are presented in the tables. 2. Data analysed as MD between treatment groups via generic inverse variance due to cross‐over design of the trial, therefore an estimate of the assumed risk is not available. 3. Downgraded once due to risk of bias: high risk of detection bias as participants could discern the taste of the intervention and limited information was provided about the methodological design of the trial. 4. Downgraded once due to applicability: results apply only to those who can tolerate hypertonic saline. 5. Downgraded once due to imprecision: cross‐over trial analysed as a parallel trial due to available data, this approach is likely to over‐estimate the within study variability and increase imprecision, also small sample size. 6. Downgraded once due to applicability: results apply only to those who can tolerate hypertonic saline and the trial included only participants under the age of 18 so results may not apply to adults. 7. Downgraded once due to imprecision: small sample size.