Risk of colorectal cancer from alcohol consumption at lower vitamin intakes. A hospital-based case-control study in Poland.

Abstract

The purpose of the study was to assess the relation between the simultaneous exposure to alcohol and consumption of micronutrients that have protective properties against colorectal cancer. A hospital-based case-control study of colorectal cancer was carried out between January 1998 and November 1999 at the University Hospital in Krakow, Poland. In total, 180 incident cases of colorectal cancer, confirmed by histopathology, were recruited and an equal number of controls, individually matched by gender and age (+/-5 y), were chosen amongst patients with no history of cancer. A food-frequency questionnaire for 148 food items, combined with the quantity of foods eaten, was used to assess the normal dietary pattern. The data confirmed the reported inverse association between the intake of retinol, thiamine, or antioxidant micronutrients (vitamins C, E) and the occurrence of colorectal cancer. Alcohol intake was found to be an important risk factor for this cancer site, and the risk escalated in parallel with increased intake of retinol, carotene, vitamins C and E, but with high consumption of alcohol ran a noticeably high risk of colorectal cancer (OR= 6.79; 95% CI: 2.08-22.18). The risk was markedly lower, however, among alcohol drinkers who reported a high intake of micronutrients (OR = 1.35; 95% CI: 0.39-4.67). The data suggest that a combination of high consumption of alcohol and low intake of retinol and antioxidant vitamins may considerably increase the risk of colorectal cancer.