Alcohol consumption as a risk factor for pneumonia: a systematic review and meta-analysis

The aim of this study was to quantify the association between alcohol consumption and incidence of pneumonia and to examine possible pathways. This was done by a systematic review and meta-analyses on the dose-response relationship between alcohol consumption or alcohol-use disorders and the incidence of community-acquired pneumonia (CAP). The relative risk (RR) of CAP increased monotonically with increasing alcohol consumption. Individuals consuming 24, 60, and 120 g of pure alcohol daily demonstrated RRs for incident CAP of 1.12 (95% CI 1.02-1.23), 1.33 (95% CI 1.06-1.67) and 1.76 (95% CI 1.13-2.77), respectively, relative to non-drinkers. Clinically defined alcohol-use disorders were associated with an eightfold increased risk of CAP (RR 8.22, 95% CI 4.85-13.95). In conclusion, alcohol was found to be a risk factor for pneumonia with a clear statistical association, and a monotonic dose-response relationship.