Metabolic health is a determining factor for incident colorectal cancer in the obese population: A nationwide population-based cohort study

Abstract

Background: The association of the risk of colorectal cancer (CRC) with obesity or obesity-induced metabolic disturbances remains controversial. We assessed the association of metabolic health status with incident CRC among subjects with obesity. Methods: This study included 319,397 subjects from the Korean National Health Insurance Service-National Health Screening Cohort. Transitions in metabolic health status and obesity were examined during 2009?2010 and 2011?2012. We categorized subjects with obesity into four separate groups according to their dynamic metabolic health status: metabolically healthy obesity (MHO), MHO to metabolically unhealthy obesity (MUO), MUO to MHO, and stable MUO. Subjects were followed up from 2009 to 2015 for incident CRC. Results: The stable MHO group showed no increased risk of incident CRC (hazard ratio [HR], 0.97; 95% confidence interval [CI], 0.83?1.14). However, the MHO to MUO group had a higher risk of incident CRC than the stable metabolically healthy nonobese (MHNO) group (HR, 1.34; 95% CI, 1.15?1.57). Among patients with MUO at baseline, those in the subgroup who transitioned to MHO group were not at increased risk of CRC (HR, 1.06; 95% CI, 0.91?1.25), whereas those who remained in the stable MUO group had a higher risk of incident CRC than those in the stable MHNO group (HR, 1.29; 95% CI, 1.19?1.41). Conclusions: The transition of metabolic health was a determining factor for CRC among subjects with obesity. Hence, maintenance or recovery of metabolic health should be addressed to prevent CRC in individuals with obesity.