Abstract
Colorectal neoplasm is considered to have a strong association with nonalcoholic fatty liver disease (NAFLD) and metabolic syndrome (MetS), respectively. The relationship among NAFLD, MetS, and colorectal neoplasm was assessed in 1793 participants. Participants were divided into 4 groups based on the status of NAFLD and MetS. Relative excess risks of interaction (RERI), attributable proportion (AP), and synergy index (SI) were applied to evaluate the additive interaction. NAFLD and MetS were significantly correlated with colorectal neoplasm and colorectal cancer (CRC), respectively. The incidence of CRC in NAFLD (+) MetS (+) group was significantly higher than other 3 groups. The result of RERI, AP, and SI indicated the significant additive interaction of NAFLD and MetS on the development of CRC. NAFLD and MetS are risk factors for colorectal neoplasm and CRC, respectively. And NAFLD and MetS have an additive effect on the development of CRC.