High Adherence to Repeat Multitarget Stool DNA Testing and Follow-Up Colonoscopy in Average-Risk United States Adults: Results from a Nationally Insured Cohort.

[PURPOSE] Colorectal cancer (CRC) is a leading cause of cancer-related deaths in the United States, despite available screening programs, making regular screening essential for early detection and prevention. This study evaluated adherence to repeat multitarget stool DNA (mt-sDNA) testing and follow-up colonoscopy rates among average-risk individuals in the United States METHODS: This retrospective study used mt-sDNA lab data linked to a national multipayer claims database from 2017 to 2023. Adults aged 45 to 75 years at average risk for CRC who underwent repeat mt-sDNA screening after one or more prior negative results were included. The primary outcome was adherence to repeat mt-sDNA testing, defined as the return of a successfully completed test with valid results within 365 days of shipment. The secondary outcome was the rate of follow-up colonoscopy after a positive mt-sDNA result. Baseline characteristics, adherence rates, and follow-up colonoscopy rates were summarized descriptively. Logistic regression was used to identify factors independently associated with adherence.

[FINDINGS] The study included 326,329 individuals, predominantly female (62.0%) and White (62.5%). Adherence to repeat mt-sDNA screening was high across all racial and ethnic subgroups, exceeding 80% in every group analyzed. White individuals had the highest adherence at 86.6%, followed by Asian individuals at 85.7%, Black individuals at 83.1%, and Hispanic or Latino individuals at 82.7% (P < 0.001).Among those with two prior mt-sDNA tests, adherence increased to 90.6%. The rate of follow-up colonoscopy among those with a positive mt-sDNA result was 76.0%. Logistic regression analysis showed higher odds of mt-sDNA adherence among individuals aged 65-75 years (OR: 1.27; 95% CI: 1.25-1.30; P < 0.001), those residing in rural (OR: 1.21; 95% CI: 1.13-1.28; P < 0.001), patients whose tests were ordered by OB/GYNs (OR: 1.19; 95% CI: 1.13-1.28; P < 0.001), individuals receiving digital outreach (OR: 1.34; 95% CI: 1.30-1.37; P < 0.001), and individuals with two or more prior mt-sDNA tests (OR: 1.44; 95% CI: 1.31-1.58; P < 0.001).

[IMPLICATIONS] The mt-sDNA test was associated with high repeat screening adherence (86.1%) and a follow-up colonoscopy rate of 76.0%, with mt-sDNA adherence exceeding 80% in most subgroups. These findings support its utility as a reliable, home-based CRC screening option.