A pooled analysis of alcohol intake and colorectal cancer

In order to provide an updated quantification of the association between alcohol intake and colorectal cancer, we conducted a meta-analysis of published observational studies.

Two cohort and 22 case-control studies presenting results for at least three categories of alcohol intake were identified from a PubMed search of articles published before July 2014. Data were extracted independently by two reviewers. Random effects meta-analyses, subgroup analyses, and meta regression were performed for modeling the dose-response relation.

The pooled relative risk (RR) for any alcohol intake compared with non/occasional drinking was 1.13 [95% confidence interval (CI), 1.09-1.17]. The RRs were 1.07 (95% CI, 1.02-1.13), 1.23 (95% CI, 1.15-1.32) and 1.37 (95% CI, 1.26-1.49) for light (≤12.5 g/day), moderate (12.6 to 49.9 g/day) and heavy drinking (≥50 g/day), respectively. The risks were consistent in the subgroup analyses of sex and tumor site.

This meta-analysis provides strong evidence for an association between alcohol intake and colorectal cancer risk.