Lifetime and baseline alcohol intake and risk of colon and rectal cancers in the European Prospective Investigation into Cancer and Nutrition (EPIC)

Alcohol consumption may be associated with risk of colorectal cancer (CRC), but the epidemiological evidence for an association with specific anatomical subsites, types of alcoholic beverages and current vs. lifetime alcohol intake is inconsistent. Within the European Prospective Investigation into Cancer and Nutrition (EPIC), 478,732 study subjects free of cancer at enrolment between 1992 and 2000 were followed up for an average of 6.2 years, during which 1,833 CRC cases were observed. Detailed information on consumption of alcoholic beverages at baseline (all cases) and during lifetime (1,447 CRC cases, 69% of the cohort) was collected from questionnaires. Cox proportional hazard models were used to examine the alcohol-CRC association. After adjustment for potential confounding factors, lifetime alcohol intake was significantly positively associated to CRC risk (hazard ratio, HR = 1.08, 95%CI = 1.04-1.12 for 15 g/day increase), with higher cancer risks observed in the rectum (HR = 1.12, 95%CI = 1.06-1.18) than distal colon (HR = 1.08, 95%CI = 1.01-1.16), and proximal colon (HR = 1.02, 95%CI = 0.92-1.12). Similar results were observed for baseline alcohol intake. When assessed by alcoholic beverages at baseline, the CRC risk for beer (HR = 1.38, 95%CI = 1.08-1.77 for 20-39.9 vs. 0.1-2.9 g/day) was higher than wine (HR = 1.21, 95%CI = 1.02-1.44), although the two risk estimates were not significantly different from each other. Higher HRs for baseline alcohol were observed for low levels of folate intake (1.13, 95%CI = 1.06-1.20 for 15 g/day increase) compared to high folate intake (1.03, 95%CI = 0.98-1.09). In this large European cohort, both lifetime and baseline alcohol consumption increase colon and rectum cancer risk, with more apparent risk increases for alcohol intakes greater than 30 g/day.