Study DesignRetrospective propensity-score-matched cohort study.ObjectivesTo evaluate whether postoperative glucagon-like peptide-1 receptor agonist (GLP-1 RA) use is associated with fewer complications, lower pseudarthrosis, and improved survival after lumbar fusion in adults aged 50 years and older.MethodsThe TriNetX Global Collaborative Network was queried to identify adults ≥50 years who underwent lumbar arthrodesis (2010-2025). GLP-1 RA exposure was defined as an active prescription within 1 to 90 days postoperatively. The comparison group consisted of patients without a GLP-1 RA prescription during this window. Propensity score matching adjusted for demographics, BMI, hemoglobin A1c, preoperative GLP-1 RA use, and comorbidities. Outcomes: 90-day and 1-year infectious, pulmonary, and thromboembolic complications, 1-year pseudarthrosis, and 1-year mortality rates. Survival was assessed with Kaplan Meier and Cox regression.ResultsAmong 169 286 patients who underwent lumbar arthrodesis, 1844 had postoperative GLP-1 RA use and 167 442 did not. After matching, 1816 patients remained in each cohort. Postoperative GLP-1 RA use was associated with lower 90-day pneumonia (Risk Ratio [RR] 0.51), surgical site infection (RR 0.58), sepsis (RR 0.64), urinary tract infection (RR 0.56), wound dehiscence (RR 0.46), and venous thromboembolism (RR 0.54) (all < 0.05), and 1-year lower hazard of death (HR 0.38; = 0.018).ConclusionIn this large propensity-score-matched cohort, postoperative GLP-1 RA use was associated with fewer early infectious, pulmonary, wound, and thromboembolic complications and improved 1-year survival after lumbar spinal fusion.