Use of GLP-1 Receptor Agonists Prior to Lumbar Spine Surgery

Introduction: Obesity is a modifiable risk factor for degenerative spine disease and has been associated with worse perioperative and long-term spine surgical outcomes. Recently, GLP-1 receptor agonists (GLP-1RAs) have revolutionized treatment of obesity. Our aim was to study lumbar spine surgery outcomes in patients previously treated with GLP-1RAs.

Methods: This was a single-center, retrospective cohort study of adult patients undergoing lumbar surgery between 2018-2024. Patients prescribed a GLP-1RA ≥2 months prior to surgery were included in the treated cohort. A 2:1 propensity score-matched untreated cohort was selected based on age, sex, insurance, diabetes, procedure type, and BMI when starting GLP-1RA. Untreated patients were matched based on their BMI measurement at a similar timepoint prior to surgery as the treated patient had started a GLP-1RA. Therefore, the cohorts could differ in BMI by the time of surgery. Standardized mean differences of matching variables were verified as < 0.1. Outcomes analyzed included BMI change prior to surgery, blood loss, surgery duration, readmission/reoperation rates, and postoperative change in PROMIS Physical Function and Pain Interference. Outcomes were compared using Mann-Whitney or Chi-square tests and reported as median [Q1,Q3].

Results: Clinical and surgical characteristics were similar between the GLP-1RA (N=127) and untreated (N=254) cohorts. The GLP-1 cohort had a greater percent weight loss before surgery (GLP-1: -4.3% [-10.1, 0.5], untreated: -0.6% [-6.3, 2.1], p<.001). Blood loss, surgery duration, and readmission/reoperation rates were not significantly different between cohorts. The GLP-1RA group had greater improvement in physical function (GLP-1: 5.7 [2.2, 11.1], untreated: 4.2 [-1.3, 7.9], p=.04), but this outcome was only available in one-third of patients.

Conclusion : Patients lost weight taking GLP-1RAs and appear to have comparable or better surgical outcomes. This highlights the potential role for these medications in perioperative optimization and supports a future randomized clinical trial.