One-Year Weight Reduction With Semaglutide or Liraglutide in Clinical Practice.

IMPORTANCE: Limited data are available on long-term weight loss achieved with semaglutide or liraglutide for type 2 diabetes (T2D) or obesity in clinical practice. OBJECTIVE: To document weight loss achieved with injectable forms of semaglutide or liraglutide and identify factors associated with weight reduction of 10% or greater at 1 year. DESIGN, SETTING, AND PARTICIPANTS: This retrospective cohort study used electronic health records from a large, integrated health system in Ohio and Florida. Participants included adults with a body mass index (calculated as the weight in kilograms divided by the height in meters squared) of at least 30.0 who initiated treatment with semaglutide or liraglutide between July 1, 2015, and June 30, 2022. Follow-up was completed July 28, 2023. EXPOSURE: Injectable forms of semaglutide or liraglutide approved for T2D or obesity. MAIN OUTCOMES AND MEASURES: Percentage weight change and categorical weight reduction of 10% or greater at 1 year. RESULTS: A total of 3389 patients (mean [SD] age, 50.4 [12.2] years; 1835 [54.7%] female) were identified. Of these, 1341 patients received semaglutide for T2D; 1444, liraglutide for T2D; 227, liraglutide for obesity; and 377, semaglutide for obesity. Mean (SD) percentage weight change at 1 year was -5.1% (7.8%) with semaglutide vs -2.2% (6.4%) with liraglutide (P < .001); -3.2% (6.8%) for T2D as a treatment indication vs -5.9% (9.0%) for obesity (P < .001); and -5.5% (7.5%) with persistent medication coverage (ie, a cumulative gap of less than 90 days) at 1 year vs -2.8% (7.0%) with 90 to 275 medication coverage days and -1.8% (6.7%) with fewer than 90 medication coverage days (P < .001). In the multivariable model, semaglutide vs liraglutide (adjusted odds ratio [AOR], 2.19 [95% CI, 1.77-2.72]), obesity as a treatment indication vs T2D (AOR, 2.46 [95% CI, 1.83-3.30]), persistent medication coverage vs 90 medication coverage days (AOR, 3.36 [95% CI, 2.52-4.54]) or 90 to 275 medication coverage days within the first year (AOR, 1.50 [95% CI, 1.10-2.06]), high dosage of the medication vs low (AOR, 1.58 [95% CI, 1.11-2.25]), and female sex (AOR, 1.57 [95% CI, 1.27-1.94]) were associated with achieving a 10% or greater weight reduction at year 1. CONCLUSIONS AND RELEVANCE: In this retrospective cohort study of 3389 patients with obesity, weight reduction at 1 year was associated with the medication's active agent, its dosage, treatment indication, persistent medication coverage, and patient sex. Future research should focus on identifying the reasons for discontinuation of medication use and interventions aimed at improving long-term persistent coverage.