A meta-analysis on alcohol drinking and the risk of Hodgkin lymphoma

The role of alcohol intake in the risk of Hodgkin lymphoma (HL) is still largely unclear. To summarize the evidence on the issue, we carried out a meta-analysis of the available studies. We identified eight case-control and two cohort studies, including a total of 1488 cases of HL. We derived meta-analytic estimates using random-effects models, taking into account the correlation between estimates, and carried out a dose-risk analysis using nonlinear random-effects metaregression models. Compared with nondrinkers, the relative risk for alcohol consumers was 0.70 [95% confidence interval (CI), 0.60-0.81] overall, 0.66 (95% CI, 0.56-0.78) among case-control, and 0.92 (95% CI, 0.63-1.33) among cohort studies. Compared with nondrinkers, the pooled relative risks were 0.71 (95% CI, 0.57-0.89) for light (i.e. <=1 drink/day) and 0.73 (95% CI, 0.60-0.87) for moderate-to-heavy (i.e. >1 drink/day) alcohol drinking. This meta-analysis suggests a favourable effect of alcohol on HL, in the absence, however, of a dose-risk relationship. The inverse association was restricted to - or greater in - case-control as compared with cohort studies. This indicates caution in the interpretation of results.