Colorectal Cancer Screening Uptake Across Age Groups in an Academic Health System

This study aimed to evaluate colorectal cancer screening uptake in an academic setting after updated guidelines to initiate screening at age 45 years, focusing on differences between adults aged 45-49 years and 50-75 years, and by sociodemographic characteristics.

This was a retrospective cohort of insured, average risk adults aged 45-75 years receiving care in the University of California San Diego Health System between 2021 and 2023. Electronic health records were used to capture colorectal cancer screening uptake and modality, individual-level sociodemographic factors, and linkage to ZIP code-level social vulnerability measures. Colorectal cancer screening adherence was measured by calendar year and compared between ages 45-49 years and 50-75 years using multivariable Poisson regression with robust standard errors.

Adults aged 45-49 years experienced increased screening adherence from 20% in 2021 to 46% in 2023. Their screening adherence likelihood were lower than adults aged 50-75 years across all years (2021 adjusted prevalence ratio [aPR]=0.27, 95% CI=0.25, 0.29; 2022 aPR=0.45, 95% CI=0.43, 0.48; 2023 aPR=0.59, 95% CI= 0.56, 0.62). Colonoscopy was the primary screening modality, though adults aged 45-49 years increased stool-based testing from 3% in 2021 to 9% in 2023. All racial and ethnic groups showed increased screening adherence from 2021 to 2023, leaving existing screening disparities unchanged.

Adults aged 45-49 years had lower colorectal cancer screening adherence likelihood than adults aged 50-75 years and had increasing interest in stool-based test modalities between 2021 and 2023. Despite concerns guideline changes could increase screening disparities, colorectal cancer screening adherence increased across all racial and ethnic groups, though gaps between groups did not change. The findings highlight screening promotion successes at one academic center, while emphasizing the need for focused interventions to continue minimizing disparities and improving adherence.