Abstract
Background and Aims: The association between obesity and colorectal cancer (CRC) is well established in older individuals, but evidence is limited in the younger population. The study aims to analyze the relationship of obesity and its related comorbidities in early-onset CRC (E-CRC) and compare it to late-onset CRC (L-CRC). Methods: A retrospective, cross-sectional study was performed on average-risk individuals ≥ 20 years who were active patients in the commercial database, IBM Watson Health Explorys in the last 5 years. Individuals with CRC were compared to those without CRC across different age groups (20–39, 40–49, and 50–74 years). Individuals with CRC diagnosed < 50 years (E-CRC) were compared to those with CRC between 50 and 74 years (L-CRC). Variables included sex, smoking, obese BMI, diabetes mellitus type 2 (DM2), hypertension (HTN), and hyperlipidemia (HLD). Since Explorys aggregates population-level, de-identified data, approval from institutional review board was not required. Results: Among 37,483,140 individuals, 162,150 cases of sporadic CRC were identified. Compared to the general population, obesity and HLD were independent risk factors for CRC across all age groups; DM2, HTN, and smoking were independent risk factors for CRC in men of all age groups and women with L-CRC. Compared to L-CRC, individuals with E-CRC had lower percentages of obesity-related comorbidities. Conclusion: In E-CRC, obesity, DM2, HTN, HLD, and smoking are independent risk factors for CRC among men; obesity and HLD are independent risk factors for CRC in women. These subgroups may benefit from a personalized screening approach to detect early-onset CRC. © 2020, Springer Science+Business Media, LLC, part of Springer Nature.