Association between Abdominal Obesity and Incident Colorectal Cancer: A Nationwide Cohort Study in Korea

Background: We investigated the association of w May aist circumference (WC) and abdominal obesity with the incident colorectal cancer risk in Korean adults. Methods: This nationwide population-based cohort study was based on health insurance claims data. We analyzed data from 9,959,605 participants acquired through health check-ups of the Korean National Health Insurance Service in 2009 who were followed up until the end of 2017. We performed multivariable Cox proportional hazards regression analysis. Results: During 8.3 years of follow up, 101,197 cases (1.0%) of colorectal cancer were recorded. After adjusting for potential confounders, there was a positive association between WC and colorectal cancer risk (pfor trend <0.001). Abdominal obesity was associated with an increased risk of colorectal (hazard ratio: 1.10, (95% confidence interval: 1.08-1.12)), colon (1.11, 1.09-1.13), and rectal cancer (1.08, 1.05-1.10). These associations were independent of body mass index and were more pronounced in men and elderly individuals. Conclusion: We revealed that higher WC is related to colorectal cancer risk, thus suggesting that abdominal obesity may be a risk factor for colorectal cancer in this East Asian population.