Summary of findings 6. Cycled inhaled tobramycin compared to culture‐based inhaled tobramycin.
| Cycled inhaled tobramycin compared to culture‐based inhaled tobramycin for eradicating Pseudomonas aeruginosa in people with cystic fibrosis | ||||||
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Patient or population: adults and children with cystic fibrosis and a positive microbiological isolate of P aeruginosa from a respiratory tract specimen Settings: outpatients Intervention: cycled inhaled tobramycin Comparison: culture‐based inhaled tobramycin | ||||||
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No of Participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Assumed risk | Corresponding risk | |||||
| Culture‐based inhaled tobramycin | Cycled inhaled tobramycin | |||||
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Eradication of P aeruginosa from the respiratory tract: proportion of participants with one or more isolates of P aeruginosa from the respiratory tract Follow‐up: 18 months |
467 per 1000 | 228 per 1000 (145 to 383 per 1000) |
OR 0.51 (95% CI 0.31 to 0.82) | 2981 (1 RCT) | ⊕⊕⊕⊝ moderate2 | The original trial report published age group–adjusted ORs which are slightly different to the results of this review. |
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FEV₁: mean 70‐week % change in FEV₁ (% predicted) Follow‐up: 70 weeks |
The mean 70‐week % change in FEV₁ (% predicted) was ‐1.61% in the culture‐based inhaled tobramycin group. | The mean 70‐week % change in FEV₁ (% predicted) was 2.38% higher (2% lower to 6.76% higher) in the cycle‐based inhaled tobramycin group. |
NA | 1431 (1 RCT) | ⊕⊕⊝⊝ low2,3 | |
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FVC Follow‐up: NA |
Outcome not reported. | NA | NA | NA | ||
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Growth and nutritional status: mean 70‐week change from baseline in weight (kg) and height (cm) Follow‐up: 70 weeks |
There were no significant differences between treatment groups in mean 70‐week change from baseline in weight (kg) or height (cm). | NA | 3041 (1 RCT) | ⊕⊕⊕⊝ moderate2 | ||
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Frequency of infective pulmonary exacerbations: proportion of participants with one or more pulmonary exacerbations (any severity) Follow‐up: 18 months |
533 per 1000 | 400 per 1000 (256 to 624 per 1000) |
OR 0.75 (95% 0.48 to 1.17) | 3041 (1 RCT) | ⊕⊕⊕⊝ moderate2 | There was also no significant difference between groups in terms of proportion of participants with one or more severe pulmonary exacerbation or in terms of time to pulmonary exacerbation (severe or any severity). |
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Isolation of other micro‐organisms from the respiratory tract: proportion of participants with new isolates of Stenotrophomonas maltophilia Follow‐up: 18 months |
184 per 1000 | 217 per 1000 (118 to 390 per 1000) |
OR 1.18 (95% CI 0.65 to 2.12) | 2791 (1 RCT) | ⊕⊕⊕⊝ moderate2 | |
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Adverse effects to antibiotics: proportion of participants with one or more serious adverse events Follow‐up: 18 months |
289 per 1000 | 246 per 1000 (147 to 405 per 1000) |
OR 0.85 (95% 0.51 to 1.40) | 3041 (1 RCT) | ⊕⊕⊕⊝ moderate2 | |
| *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 one second; FVC: forced vital capacity; NA: not applicable; NR: not reported OR: odds ratio; P aeruginosa: Pseudomonas aeruginosa; RCT: randomised controlled trial | ||||||
| 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. In the included trial, 306 participants were randomised, 304 received treatment but not all participants contributed to all outcomes (unclear how many participants contributed to some outcomes, spirometry not performed in very young children (less than 4 years of age)).
2. Downgraded once due to applicability: the included studies recruited only children; results are not applicable to adults. Also the included trial required patients to have been free of P aeruginosa for at least two years so results may not be applicable to a wider population.
3. Downgraded once due to applicability: a large proportion of the randomised and treated participants (161 out of 304, 53%) did not contribute to this outcome.