Effectiveness of angiotensin converting enzyme inhibitors in preventing pneumonia: A systematic review and meta‐analysis

We performed a systematic review and meta‐analysis to re‐evaluate the effectiveness of angiotensin‐converting enzyme inhibitors (ACE‐I) in the reduction of pneumonia risk. We searched relevant publications in five databases. All studies included patients older than 18 years, who had used ACE‐I as an intervention, and had assessed pneumonia. Seven RCTs (n = 8704) and 38 observational studies (n = 1,705,030) were included. The overall risk of bias was high. ACE‐I‐treated patients were associated with a slightly lower risk of pneumonia, both from pooled estimates of RCTs [pooled odds ratio (OR), 0.75; 95% confidence interval (CI), 0.62–0.90; low certainty of evidence] and observational studies (pooled OR, 0.85; 95% CI, 0.78–0.92; very low certainty of evidence). Considering the small effect size of ACE‐I in preventing pneumonia and the low quality of the evidence, routine use of ACE‐I for pneumonia prevention is not recommended.