WHILST alcohol intake has long been associated with a higher risk of colorectal cancer risk, limited research has been undertaken regarding the effect of lifelong alcohol drinking. Recently, O’Connell et al. published a study with the ambition of rectifying this critical research gap. The objective of the study was to investigate, and ultimately estimate, the respective associations of both higher average lifetime alcohol drinking and consistent heavy alcohol intake with the incident of colorectal adenoma and cancer.
Lifelong Alcohol Consumption and Adenoma
O’Connell at al. analysed data from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial and calculated the average lifetime alcohol intake of US adults enrolled in the trial by averaging drinks per week from age 18 years until the current drinking frequency study baseline. Alcohol consumption patterns were determined by past and current drinking frequency. 12,327 participants with a negative baseline screen were observed. Amongst this number, 812 were found to have an adenoma following a second screen.
Estimate odds ratios (OR) and 95% confidence intervals (CI) for incident of adenoma were estimated using logistic regression. Over the course of 20 years, follow-ups concluded 1,679 cases of colorectal cancer amongst the 88,092 participants. O’Connell and colleagues then used Cox proportional hazards regression to estimate hazard rations (HR) and 95% CI for colorectal cancer.
Estimated Risks of Alcohol Intake
Results concluded that current drinkers with an average lifetime alcohol intake of 14 or more drinks per week had a 25% higher risk of colorectal cancer (HR, 1.25; 95% CI, 1.01–1.53) when compared with those with an average lifetime intake of one drink or less per week. A positive association was found between consistent heavy drinking, versus light drinking, and colorectal cancer risk (HR: 1.91; 95% CI: 1.17–3.12).
The study also suggests the benefits of alcohol cessation, as former drinkers, when compared to current drinkers averaging less than one drink per week, were observed to have lower odds of nonadvanced adenoma (OR, 0.58; 95% CI, 0.39–0.84).
Alcohol Cessation and Cancer Risk
Overall, the study concludes consistent heavy alcohol consumption and higher average lifetime alcohol drinking may increase colorectal cancer risk, whereas cessation of drinking may lower the risk of adenoma. These insights further research into the carcinogenic potential of alcohol and could lead to further research regarding the effect of lifetime alcohol intake and, conversely, alcohol cessation on other malignancies and tumour sites.
References
O’Connell et al. Association of alcohol intake over the lifetime with colorectal adenoma and colorectal cancer risk in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. Cancer. 2026;132(3):e70201.
