Metabolic syndrome is a risk factor for adenoma occurrence at surveillance colonoscopy

We investigated the risk factors for adenoma occurrence at surveillance colonoscopy, especially focusing on patient characteristics, including metabolic factors.Surveillance colonoscopy intervals depend on baseline adenoma characteristics. However, patients' characteristics may also influence the occurrence of adenomas.Of 62,171 asymptomatic subjects who underwent colonoscopy for a health check-up between 2010 and 2011, 4869 subjects who underwent follow-up colonoscopy between 2012 and 2013 were included in this longitudinal study. The risk of adenoma occurrence was assessed using Cox proportional hazards modeling.Of 4869 subjects, 2827 (58.1%), 1619 (33.3%), and 423 (8.7%) were assigned to the normal, low-risk, and high-risk groups, respectively, according to baseline adenoma characteristics. The mean interval between initial and follow-up colonoscopy was 2.2 ± 0.6 years. Certain patient factors, including older age (≥50 years; adjusted hazard ratio [aHR], 2.08; 95% CI, 1.73-2.49), male sex (aHR, 1.69; 95% CI, 1.30-2.19), metabolic syndrome (MetS) (aHR, 1.28; 95% CI, 1.09-1.51), obesity (aHR, 1.17; 95% CI, 1.02-1.34), elevated fasting blood glucose levels (aHR, 1.37; 95% CI, 1.19-1.58), and elevated triglyceride levels (aHR, 1.19; 95% CI, 1.03-1.37), as well as baseline adenoma characteristics, were associated with a higher risk of adenoma occurrence at follow-up colonoscopy. The cumulative incidence of adenoma occurrence in the high-risk group was higher than that in the low-risk group, whereas the incidence in the high-risk group without MetS was comparable with that in the low-risk group with MetS.Patient characteristics, such as MetS, obesity, older age, and male sex, in addition to adenoma characteristics, were independent risk factors for adenoma occurrence at surveillance colonoscopy. These patient characteristics may be considered in surveillance colonoscopy intervals.