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.