Summary of findings 1. PPI plus usual care versus usual care alone or chronic obstructive pulmonary disease.
| Usual care plus PPI compared to Usual care plus alone for chronic obstructive pulmonary disease | ||||||
| Patient or population: chronic obstructive pulmonary disease Setting: hospital outpatients in Japan (three secondary care hospitals and one tertiary care hospital) Intervention: Usual care plus PPI Comparison: Usual care plus alone | ||||||
| Outcomes | Anticipated absolute effects* (95% CI) | Relative effect (95% CI) | № of participants (studies) | Certainty of the evidence (GRADE) | Comments | |
| Risk with Usual care plus alone | Risk with Usual care plus PPI | |||||
| Exacerbation rate (participants with one or more) study duration: 12 months |
Study population | RR 0.46 (0.26 to 0.81) | 100 (1 RCT) | ⊕⊕⊝⊝ LOW ab | The frequency of exacerbations improved with intervention. | |
| 520 per 1,000 | 239 per 1,000 (135 to 421) | |||||
| Pneumonia and other serious adverse events | — | — | — | — | Not reported | |
| Quality of life | — | — | — | — | Not reported | |
| Lung function indices | — | — | — | — | Not reported | |
| Acute respiratory infections study duration: 12 months |
Study population | RR 0.96 (0.67 to 1.39) | 100 (1 RCT) | ⊕⊝⊝⊝ VERY LOW abc | No clear benefit or harm from PPI | |
| 540 per 1,000 | 518 per 1,000 (362 to 751) | |||||
| Disease‐specific adverse events | — | — | — | — | Not reported | |
| *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; PPI: proton pump inhibitor; RR: Risk ratio | ||||||
| GRADE Working Group grades of evidence High certainty: We are very confident that the true effect lies close to that of the estimate of the effect Moderate certainty: 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 certainty: Our confidence in the effect estimate is limited: The true effect may be substantially different from the estimate of the effect Very low certainty: We have very little confidence in the effect estimate: The true effect is likely to be substantially different from the estimate of effect | ||||||
aDowngraded by one level for imprecision: single small trial describes this result
bDowngraded by one level for study limitations: no blinding of participants and personnel
cDowngraded by one level for study limitations: the rate and number of common colds using outcomes that tend to be subjective