Abstract

Colorectal cancer (CRC) incidence at ages <50 years is increasing, leading to proposals lower the CRC screening initiation age to 45 years. Data on the effectiveness of CRC screening at ages 45-49 years are lacking.We studied the association between undergoing colonoscopy at ages 45-49 or 50-54 years and CRC incidence in a retrospective population-based cohort study using Florida's linked Healthcare Cost and Utilization Project databases with mandated reporting from 2005-2017, and Cox models extended for time-varying exposure.Among 195,600 persons with and 2.6 million without exposure to colonoscopy at ages 45-49 years, 276 and 4,844 developed CRC, resulting in CRC incidence rates of 20.8 (95% confidence interval [CI], 18.5-23.4) and 30.6 (95% CI, 29.8-31.5) per 100,000 person-years, respectively. Among 660,248 persons with and 2.4 million without exposure to colonoscopy at ages 50-54 years, 798 and 6,757 developed CRC, resulting in CRC incidence rates of 19.0 (95% CI, 17.7-20.4) and 51.9 (95% CI, 50.7-53.1) per 100,000 person-years, respectively. The adjusted hazard ratios for incident CRC after undergoing compared with not undergoing colonoscopy were 0.50 (95% CI, 0.44-0.56) at ages 45-49 years and 0.32 (95% CI, 0.29-0.34) at ages 50-54 years. The results were similar for women and men (0.48 [95% CI, 0.40-0.57] and 0.52 [95% CI, 0.43-0.62] at ages 45-49 years, and 0.35 [95% CI 0.31-0.39] and 0.29 [95% CI 0.26-0.32] at ages 50-54 years, respectively).Colonoscopy at ages 45-49 years or 50-54 years was associated with substantial decreases in subsequent CRC incidence. These findings can inform screening guidelines.

View details for DOI 10.1053/j.gastro.2021.02.015

View details for PubMedID 33577872