S276 Does Hepatitis C Independently Increase the Risk of Colorectal Adenoma?

Abstract

Introduction: Hepatitis C virus (HCV) infection has been associated with extrahepatic malignancies, one such is colorectal carcinoma (CRC). The majority of CRC arise from adenomatous polyps, it is not known if HCV infection influences the growth of these precancerous lesions. This study evaluates the prevalence of colorectal adenomas in HCV patients compared to the general population and if HCV is an independent risk factor for the detection of colorectal adenomas. Methods: This case-control study included patients who underwent screening colonoscopy at our hospital. Patients were divided into cases (HCV) and controls (non-HCV). Patients with no biopsy reports, hepatitis B, and inflammatory bowel disease were excluded. Colonoscopy findings were stratified on the biopsy results i.e., hyperplastic, adenomatous, CRC or normal mucosa. Continuous variables were analyzed using Mann Whitney U test and categorical variables using Chi-square and Fisher's exact test with p< 0.05 considered statistically significant. After 1:1 propensity score matching (PSM), a matched cohort of cases and controls was generated. A multivariate regression analysis to compute an odds ratio for colorectal adenoma detection rate was done. Results: 415 patients were screened, of which 109 HCV patients and 97 controls were included. Descriptive analysis showed that age (p = 0.03), BMI (p = 0.001), aspirin (p = 0.01), smoking (p = 0.004), alcohol use (p = 0.01) and adenoma detection (p = 0.006) were significantly different between both groups. After propensity matching, multivariate regression analysis showed patients with HCV had odds ratio (OR) = 2.06 (p = 0.03), and aspirin use had OR = 0.38 (p = 0.01) in having colorectal adenoma. (Table) Conclusion: Our study shows a significantly higher rate of adenomas in chronic HCV patients. On multivariate analysis with and without propensity score matching, HCV infection was found to be an independent risk factor for colorectal adenoma. Current guidelines do not recommend earlier screening for CRC for such patients. Prospective studies would be required to assess if treatment of HCV leads to lower adenoma detection rates. Table 1. - Multivariate logistic regression for colorectal adenoma detection Variables p value Odds ratio Lower Limit of 95% CI Upper Limit of 95% CI Age ( >60, median) 0.0295* 1.043 1.034 2.125 Hepatitis C 0.0314* 2.152 1.125 3.810 Family history of CRC 0.220 1.984 0.665 5.922 Aspirin use 0.0116* 0.387 0.253 0.89 Smoking 0.499 1.229 0.677 2.231 Alcohol use 0.293 1.527 0.694 3.359 Female Gender 0.869 1.050 0.586 1.882 Diabetes Mellitus 0.529 1.244 0.630 2.459 HIV 0.895 1.148 0.150 8.806