Risk Factors Associated With Early-onset Colorectal Cancer

Abstract Background & Aims The incidence of colorectal cancer (CRC) is increasing in individuals younger than 50 years, who do not usually undergo screening if they are of average risk. We sought to identify risk factors for CRC in this population. Methods We compared sociodemographic and medical characteristics of patients who received a diagnosis of CRC at an age of 18–49 years (early-onset) with patients who received a diagnosis of CRC at an age of 50 years or older (late-onset) and with age-matched, cancer-free individuals (controls) at a tertiary academic hospital. We collected data from all adult patients with a diagnosis of CRC from January 1, 2011 through April 3, 2017 from electronic health records. Associations with risk factors were assessed using univariable and multivariable logistic regression models. Results We identified 269 patients with early-onset CRC, 2802 with late-onset CRC, and 1122 controls. Compared with controls, patients with early-onset CRC were more likely to be male (odds ratio [OR], 1.87; 95% CI, 1.39–2.51), have inflammatory bowel disease (IBD) (3% vs 0.4% for controls; univariable P Conclusions In a retrospective study of patients with early-onset CRC vs late-onset CRC or no cancer, we identified non-modifiable risk factors, including sex, race, IBD, and family history of CRC, to be associated with early-onset CRC.