Introduction: Incidence of colorectal neoplasia (CRN) in patients < 50 years of age has been increasing. Although current guidelines recommend starting screening at age 45, data on the prevalence and characteristics of CRN in this cohort is sparse. We aim to determine the overall prevalence and characteristics of CRN lesions in patients < 50.
Methods: All patients < 50 years who underwent colonoscopy for any indication between Jan 2012 and Dec 2018 were included. Data on demographics, comorbidities, risk factors and indications was obtained. Procedural data on number of polyps and polyp characteristics was collected. Patients with inadequate preparation, personal history of (h/o) colon polyps or cancer and inflammatory bowel disease were excluded. Logistic regression analysis was used to determine predictors of adenoma detection.
Results: 4587 patients had diagnostic colonoscopy during the study period. Mean age was 38.1 years, with 61.2% females, 84% white. Abdominal pain (36%), family h/o CRC (29.5%), diarrhea (29.3%), hematochezia (25.7%) and constipation (21.2%) were the most common indications. Information on clinical characteristics based on age groups are shown in Table 1. 26.2% (n=1201) had at least one polyp; 14.8%, 31.9% and 39.4% were < 39, 40-44 and 45-49 years of age respectively. Overall adenoma prevalence was 15.8%; 7.81%, 19.9% and 24.9% were < 39, 40-44 and 45-49 respectively. ≥ 3 adenomas were observed in 6.9%; prevalence increased with age (Image 1a). Majority of the polyps were tubular adenomas (45.6%), followed by sessile serrated adenomas (17.2%); tubulovillous adenomas were the least common (2.7%). High-grade dysplasia and carcinoma were observed in 0.4% and 0.8% (Image 1b). On multivariate analysis of 1602 patients (801 with polyps and 801 age-sex matched controls), female sex (OR 0.79) and age < 39 (OR 0.63) were associated with lower odds, while family h/o polyps (OR 1.76) and BMI (1.04) were associated with higher odds of adenoma detection (Table 1).
Discussion: There was an increasing trend in the prevalence of polyps, adenomas, advanced adenomas and CRC with increasing age; our rates were similar to other published studies. Prevalence rates for all the above doubled between age groups < 39 and 40-44, but with a smaller proportion of increase between 40-44 and 45-49. Large population studies are needed to confirm this observation. Male gender, increasing age, obesity and family h/o colon polyps were independent predictors of adenoma detection in our cohort.
