Summary of findings 3. Endobronchial coils versus control.
| Endobronchial coils + optimal medical care versus optimal medical care for the treatment of chronic obstructive pulmonary disease | ||||||
| Patient or population: Participants suffering from chronic obstructive pulmonary disease Setting: Hospital Intervention: Endobronchial coils + optimal medical care Comparison: Optimal medical care | ||||||
| Outcomes | Anticipated absolute effects* (95% CI or SD) | Relative effect (95% CI) | № of participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Risk with optimal medical care | Risk with endobronchial coils | |||||
| % change from baseline in FEV1 | The mean % change in FEV1 for optimal medical care ranged between ‐3.0% and 3.6% | The mean change in FEV1 in the intervention group was 10.88 more (95% CI, 5.20 to 16.55) | ‐ | 146 (2 RCTs) | ⊕⊕⊕⊝ MODERATE1 | |
| Mortality at end of follow‐up | 48 per 1,000 | 70 per 1,000 | OR 1.49 (0.67 to 3.29) | 461 (3 RCTs) | ⊕⊕⊕⊝ MODERATE2 | |
| Units SGRQ change from baseline | The mean units SGRQ change for optimal medical care ranged between 0.25 and 1.5 | The mean SGRQ change in the intervention group was 9.14 units fewer (95% CI, ‐11.59 to ‐6.70) | ‐ | 461 (3 RCTs) | ⊕⊕⊕⊝ MODERATE3 | |
| Change from baseline in lung function parameters other than FEV1 | The mean L change in RV for optimal medical care ranged between ‐0.2 L and ‐0.1 L | The mean RV change in the intervention group was 0.32 L fewer (95% CI, ‐0.48 to ‐0.17 L) | ‐ | 461 (3 RCTs) | ⊕⊕⊕⊕ HIGH | |
| The mean L change in TLC for optimal medical care was ‐0.09 L | The mean TLC change in the intervention group was 0.19 L fewer (95% CI, ‐0.43 to ‐0.06) | 146 (2 RCTs) | ⊕⊕⊕⊝ MODERATE4 | |||
| The mean change in RV/TLC for optimal medical care ranged between ‐0.5 to 0 | The mean change in RV/TLC in the intervention group was 3.74 fewer (95% CI ‐5.16 to ‐2.33) | 415 (2 RCTs) | ⊕⊕⊕⊕ HIGH | |||
| Meters change from baseline in 6MWD | The mean 6MWD change from baseline ranged between ‐23 meters and ‐3.2 meters | The mean 6MWD change from baseline in the intervention group was 30.85 meters more (‐1.05 to 62.76 more) | ‐ | 461 (3 RCTs) | ⊕⊕⊝⊝ LOW5 | |
| Adverse events at end of follow‐up | 230 per 1,000 | 391 per 1,000 (297 to 492) | OR 2.14 (1.41 to 3.23) | 461 (3 studies) | ⊕⊕⊕⊕ HIGH | Overall rates of adverse events were higher in the treatment condition compared to control. Lower respiratory tract infections, COPD exacerbations, pneumonia and pneumothorax were the most frequent adverse events. |
| Cost effectiveness at end of follow‐up | The mean costs in USD at end of follow‐up for control was $5,912.00 (SD 3,529.00) | The mean cost at end of follow‐up in the intervention group was $47,908.00 higher ($47,879.00 to $48,073.00) | ⊕⊕⊕⊝ MODERATE6 | |||
| *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 1 level due to imprecision: the upper end of CI indicated 3.3 times the odds of death
3 Downgraded 1 level due to risk of performance and detection bias: 3 out of 4 studies were not blinded and SGRQ was dependent on participants' subjective answering
4 Downgraded 1 level due to risk of performance error and imprecision: low participant numbers
5 Downgraded 2 levels due to risk of performance bias and inconsistency in results: high heterogeneity and the 6MWD was effort‐dependent and could be influenced in non‐blinded studies
6 Downgraded 1 level due to imprecision: low participant numbers