Background: Sexual minorities are at a higher risk of colorectal cancer (CRC) and face unique challenges in cancer care compared to the straight population. This study aimed to examine the association between sexual orientation and adherence to the 2021 USPSTF CRC screening guidelines among adults aged 45-75 years without a history of CRC.

Methods: Using data from the 2022 Behavioral Risk Factor Surveillance System (BRFSS), we analyzed the prevalence and rate ratios of up-to-date CRC screening across various sexual orientations (straight, gay/lesbian, bisexual, and questioning) using log-binomial regression models adjusted for demographic and socioeconomic factors. Subgroup analyses were further stratified by age groups (45-49, 50-64, 65-75).

Results: The study included 171,834 (weighted n=92,167,568) individuals aged 45-75 years. Overall, CRC screening prevalence ranged from 58.6% in the questioning group to 68.9% in the straight group (p<0.001). Adjusted prevalence ratios (APR) showed that questioning individuals (APR=0.91, 95%CI: 0.85-0.99) had significantly lower screening rates than straight individuals. In subgroup analyses, questioning individuals had the lowest screening prevalence across all age groups: 45-49 (22.9% vs. 30.2%), 50-64 (61.8% vs. 69.8%), and 65-75 (69.5% vs. 83.7%) compared to straight individuals. In the 65-75 age group, questioning individuals had lower screening likelihoods than both straight (APR=0.89, 95%CI: 0.81-0.97) and gay/lesbian individuals (APR=0.90, 95%CI: 0.82-0.99).

Conclusion: Questioning individuals consistently had the lowest up-to-date CRC screening rates compared to straight and other sexual minority groups. Improving screening rates among questioning individuals, particularly those newly eligible (aged 45-49 years), is crucial for enhancing adherence to the new guidelines.