Obesity may modify the association between alcohol consumption and the risk of colorectal cancer

In this study, there was no relation of alcohol with the risk of CRC when considering the entire population. However, when subjects were stratified by BMI (<30 versus = 30), the data indicate an increase in CRC risk for obese subjects who were "drinkers" (OR=2.2, 95% CI 1.2-4.0), especially among subjects reporting 5 or more drinks/daily (OR=3.7, CI 1.5-9.0). On the other hand, even among obese subjects there was not a clear dose-response effect noted, i.e., there was not a step-wise increase in CRC risk with greater number of drinks/day. For example, the odds ratio (OR) was 2.3 times that of non-drinkers for obese subjects reporting 1-2 drinks/daily and 1.3 for those reporting 3-4 drinks/daily.

It will be interesting to determine if other studies show that there is modification of the association between alcohol intake and colorectal cancer by obesity. If such is the case, it could help understand some of the mechanisms for the development of cancer and provide better guidelines for screening for CRC.

More information: Zhao J, Zhu Y, Wang PP, et al. Interaction between alcohol drinking and obesity in relation to colorectal cancer risk: a case-control study in Newfoundland and Labrador, Canada. BMC Public Health 2012, 12:94 doi:10.1186/1471-2458-12-94

Provided by Boston University Medical Center