Association between metabolic syndrome and the risk of colorectal cancer: a prospective study in China

Objective To evaluate the correlation between metabolic syndrome (MetS) and its components on the incidence of colorectal cancer (CRC) based on data from Jinchang Cohort. Methods This is a large prospective cohort study. Between 2011 and 2020, a total of 43 516 individuals from Jinchang Cohort were included for this study. Hazard ratios (HRs) with 95% confidence intervals (CIs) for CRC according to MetS were calculated with the Cox proportional hazard models. The restricted cubic spine models with four knots were conducted to fit the dose-response relationships. Results MetS was associated with increased risk of CRC (n = 141; HR: 1.64, 95% CI: 1.15-2.33) after adjusting for confounding factors (age, sex, education level, family history of CRC, smoking index and alcohol index). Participants with hyperglycemia had a significantly higher risk of developing incident CRC (HR: 1.70; 95% CI: 1.19-2.43). The positive association between MetS and CRC was observed in males (HR: 1.76; 95% CI: 1.17-2.63), but not in females (HR: 1.24; 95% CI: 0.59-2.64). Furthermore, linear dose-response relationship was found between fasting plasma glucose (FPG) and CRC risk in males (P-overall < 0.05, Pnon-linear = 0.35). When stratified by smoke and drink, MetS was found to increase the incidence of CRC only in the smoke (HR: 2.07, 95% CI: 1.35-3.18) and drink (HR: 2.93, 95% CI: 1.51-5.69) groups. Conclusion MetS was associated with a higher risk of CRC incidence. Hyperglycemia lended strong support to the role of MetS in new-onset CRC, especially in males. Other components of MetS were not found to be associated with increased risk of CRC.