Summary of findings 6. Vapour ablation versus control.
| Vapour ablation versus optimal medical therapy for the treatment of chronic obstructive pulmonary disease | ||||||
| Patient or population: Participants suffering from chronic obstructive pulmonary disease Setting: Hospital Intervention: Vapour ablation + optimal medical care Comparison: Optimal medical care | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Risk with optimal medical care | Risk with vapour ablation | |||||
| % change from baseline in FEV1 | The mean % change in FEV1 for optimal medical care was ‐3.7 (SD 11.1) | The mean change in FEV1 in the intervention group was 14.7% more (95% CI, 7.98 to 21.42) | ‐ | 64 (1 RCT) | ⊕⊕⊝⊝ MODERATE1 | |
| Mortality at end of follow‐up | 0 per 1,000 | 44 per 1,000 | OR 2.82 (95% CI 0.13 to 61.06) | 69 (1 RCT) | ⊕⊕⊝⊝ LOW2 | |
| Units of SGRQ change from baseline | The mean units of SGRQ change for optimal medical care was 0 units (SD 9.8) | The mean SGRQ change in the intervention group was 9.70 units fewer (95% CI, ‐15.62 to ‐3.78) | ‐ | 65 (1 RCT) | ⊕⊕⊝⊝ LOW3 | |
| Lung function parameters other than FEV1 | The absolute between group difference RV in L at end of follow‐up was ‐0.3 L (95% CI ‐0.54 to ‐0.06) | ‐ | 69 (1 RCT) | ⊕⊕⊕⊝ MODERATE4 | ||
| The absolute between group difference TLC in L at end of follow‐up was ‐0.08 L (95% CI ‐0.31 to 0.16) | 69 (1 RCT) | ⊕⊕⊕⊝ MODERATE5 | ||||
| Meters at end of follow‐up in 6MWD | The absolute between group difference 6MWD in meters at end of follow‐up was 30.5 m (95% CI ‐1.5 to 62.4) | ‐ | 69 (1 RCT) | ⊕⊕⊝⊝ LOW6 | ||
| Adverse events at end of follow‐up | 125 per 1,000 | 355 per 1,000 (125 to 681) | OR 3.86 (1.00 to 14.97) | 69 (1 study) | ⊕⊕⊕⊝ MODERATE7 | COPD exacerbations, pneumonia or pneumonitis occurred more often in the treatment group compared to the control group. There were no cases of respiratory failure or ICU admission. All but one adverse events could be resolved by standard care. |
| Cost effectiveness | Not reported | not estimable | ||||
| *The risk in the intervention group (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; RR: Risk ratio; OR: Odds ratio; SGRQ: St George's Respiratory Questionnaire; FEV1: forced expired volume in one second; RV: Residual Volume; TLC: Total lung capacity; L: Liter; RCT: randomized controlled trial; 6MWD: Six‐Minute Walking Distance; SMD: Standardized Mean Difference; MD: Mean Difference | ||||||
| GRADE Working Group grades of evidence High quality: We are very confident that the true effect lies close to that of the estimate of the effect Moderate quality: We are moderately confident in the effect estimate: The true effect is likely to be close to the estimate of the effect, but there is a possibility that it is substantially different Low quality: Our confidence in the effect estimate is limited: The true effect may be substantially different from the estimate of the effect Very low quality: We have very little confidence in the effect estimate: The true effect is likely to be substantially different from the estimate of effect | ||||||
1 Downgraded 1 level due to imprecision: low participant numbers
2 Downgraded 2 levels due to imprecision: low participant numbers and high CI. Upper bound indicated 61 times the odds of death
3 Downgraded 2 levels due to imprecision and risk of performance and detection bias: low participant numbers and study was not blinded: SGRQ was dependent on participants' subjective answering
4 Downgraded 1 level due to imprecision: low participant numbers
5 Downgraded 1 level due to imprecision: low participant numbers
6 Downgraded 2 levels due to imprecision and risk of performance bias: low participant numbers and the 6MWD was effort‐dependent: can be influenced in non‐blinded studies.
7 Downgraded 1 level due to imprecision: low participant number