Effect of Glucagon-Like Peptide-1 Receptor Agonist Use on Fusion Outcomes After First Metatarsophalangeal Arthrodesis in Patients With Type 2 Diabetes Mellitus

BACKGROUND: Glucagon-like peptide-1 receptor agonists (GLP-1 RAs) influence bone metabolism by promoting formation and reducing resorption in patients with type 2 diabetes mellitus (T2DM). Although studied in hindfoot and midfoot fusion, their effect on forefoot arthrodesis remains unknown. This study evaluated 1-year fusion and complication rates after first metatarsophalangeal joint (MTPJ) arthrodesis in patients prescribed GLP-1 RAs compared with nonusers, with focused analysis in diabetics. METHODS: A retrospective cohort study was conducted using the TriNetX research network. Adults undergoing first MTPJ arthrodesis were identified and stratified by GLP-1 RA use within 1 year before surgery. Glucagon-like peptide-1 (GLP-1) users were compared with nonusers, using a subgroup analysis among patients with T2DM. Propensity score matching (1:1) was conducted using age, sex, obesity, hypertension, peripheral vascular disease, smoking status, and baseline HbA1c. All patients had at least 1 year of follow-up, and relative risks with 95% confidence intervals were calculated. RESULTS: In the primary matched analysis (n = 712 patients per cohort), rates of pseudarthrosis were similar between GLP-1 users and nonusers (7.2% vs. 8.2%; risk ratio, 0.88; P = 0.49), with no significant differences in other complications. However, in the T2DM subgroup (n = 508 patients per cohort), GLP-1 users demonstrated a lower rate of pseudarthrosis compared with diabetic control subjects (7.7% vs. 11.8%; risk ratio, 0.65; P = 0.026), while rates of implant pain, implant removal, and surgical-site infection were comparable between groups. CONCLUSION: Among patients undergoing first MTPJ arthrodesis, GLP-1 RA use was not associated with differences in overall complication rates in the general population. However, among patients with T2DM, GLP-1 use was linked to a markedly lower risk of pseudarthrosis at 1 year postoperatively. These findings suggest that GLP-1 therapy may have a favorable influence on fusion in diabetic patients and warrant additional prospective investigation. LEVEL OF EVIDENCE: III.