Background: Metabolic factors have been reported to increase the prevalence of colorectal adenomas, however, whether metabolic factors might also accelerate the recurrence after removal of adenomas has not yet been discussed. In this retrospective multicenter study, we clarified the risk factors for adenoma recurrence focusing on metabolic factors.
Methods: We analyzed the medical records of 43,195 patients who had undergone colonoscopy between January 2005 and December 2011 at 5 hospitals in Japan. Of these, the data of 1111 patients who had undergone removal of adenomas at the first screening colonoscopy, and then been followed up by colonoscopy 1 year and 2 years later were analyzed.
Results: The following 8 factors were demonstrated with a multivariate analysis as being associated with colorectal adenomas recurrence: for adenoma-related factors, 5 factors (villous features, grade of dysplasia, location and size of the largest removed adenoma, and number of the removed adenomas) were identified; for metabolic factors and other factors, 3 factors (age, body mass index (BMI), and fasting blood glucose (FBG)) were identified. A risk score (0-10 points) was developed based on these 8 factors. The risk of adenoma recurrence increased as the risk score increased. When the risk score was ≥3 (3-10) points, the odds ratio relative to <3 (0-2) points was 7.07 (95% CIs 5.30-9.43).
Conclusions: In addition to adenoma-related factors (villous features, grade of dysplasia, location, size and number), 3 factors (age, BMI and FBG) were demonstrated to influence the recurrence rate of colorectal adenoma. When the risk score was ≥3, the risk of recurrence was significantly elevated.