(716) Divergent Trends in Testosterone and GLP-1 Prescribing Across the United States: A State-Level Analysis of Medicare Part D Data (2013–2025)

Introduction In recent years, metabolic and endocrine therapies in the United States have drastically changed, specifically through the widespread adoption of glucagon-like peptide-1 agonists (GLP-1s) and the burgeoning testosterone replacement therapy (TRT) industry. Objective We assessed state-level temporal trends in per-capita testosterone and GLP-1 prescription claims to evaluate directional change and geographic variation. We further explored the hypothesis that increased GLP-1 utilization may correlate with reduced TRT prescribing, potentially reflecting GLP-1–mediated improvements in endogenous testosterone through weight loss and metabolic health. Methods Medicare Part D data (2013–2025) were analyzed for all 50 U.S. states and the District of Columbia. Annual testosterone and GLP-1 prescription claims per 100,000 population were modeled using linear regression and confirmed by Spearman correlation. States were classified as showing significant increase or decline if p < 0.05 by either method. Results Nationally, testosterone prescribing remained stable, while GLP-1 utilization rose sharply. Significant testosterone declines occurred in New York (−0.72 claims/100 k/year, p = 0.024), Massachusetts (−0.66, p = 0.041), California (−0.58, p = 0.048), and Illinois (−0.55, p = 0.049); increases were noted in Texas (+0.81, p = 0.038), Florida (+0.75, p = 0.046), and Utah (+0.71, p = 0.044). GLP-1 prescribing increased significantly in 45 of 51 jurisdictions, led by Louisiana (+49, p < 0.001), Mississippi (+41, p < 0.001), and Texas (+37, p = 0.002). No state exhibited a significant GLP-1 decline. Testosterone declines were inversely correlated with GLP-1 growth (Spearman p = −0.61, p < 0.01), most notably in the Northeast and West. Conclusions From 2013–2025, GLP-1 prescribing expanded nationwide, while testosterone utilization declined modestly or stabilized. The inverse association between GLP-1 and TRT trends suggests a shifting therapeutic landscape, potentially reflecting metabolic improvement, evolving provider attitudes, and regional heterogeneity in hormone prescribing behavior. Disclosure No