Phenome-wide analysis of downstream health outcomes following second-line antidiabetic agent prescriptions in All of Us.

Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) are increasingly prescribed for type 2 diabetes (T2D) and weight management, yet their real-world health impacts remain understudied. Using a retrospective cohort design with electronic health record data from 17,267 adults with type 2 diabetes in the All of Us Research Program, we conduct propensity score-matched phenome-wide association studies comparing diagnoses following GLP-1 RA prescription (including semaglutide-specific analyses) to those following sodium-glucose cotransporter-2 inhibitor (SGLT2i) and dipeptidyl peptidase-4 inhibitor (DPP4i) prescriptions between January 2018 and October 2023. We employ both intention-to-treat and per-protocol Cox proportional hazards models alongside restricted mean survival time analyses evaluating up to 974 phenotypes. We identify multiple phenome-wide significant and suggestive associations, including for cardiovascular, genitourinary, dental, and metabolic outcomes. Compared to SGLT2i, semaglutide demonstrates reduced risk for genitourinary infections in women (e.g., candidiasis of vulva and vagina (per-protocol hazard ratio 0.31, 95% confidence interval (0.17-0.55)). Compared to DPP4i, GLP-1 RAs are associated with reduced risk of diseases of hard tissues of teeth (0.45 (0.33-0.61)). Time-to-event analyses reveal modest delays for key diagnoses. These findings underscore differences in downstream diagnostic associations across second-line T2D therapies and highlight semaglutide's distinct profile, with implications for clinical decision-making and personalized prescribing.