Patients taking GLP-1 agonists for weight-loss prior to posterior lumbar decompression and fusion have similar surgical and patient-reported outcomes.

PURPOSE: Although glucagon-like peptide-1 receptor agonists (GRAs) are commonly used for diabetes mellitus, they are also increasingly used for weight loss. However, the impact of these medications taken solely for weight-loss on surgical outcomes has been minimally studied. The purpose of this study was to compare postoperative outcomes after lumbar fusion between patients taking (GRAs) for weight loss versus patients not taking these medications. METHODS: All adults without diabetes mellitus undergoing posterolateral decompression and fusion (PLDF) or transforaminal lumbar interbody fusion (TLIF) (2017–2023) were identified. Patients undergoing fusion for revision/trauma/malignancy/infection were excluded. Demographic/surgical variables and patient-reported outcomes were compared between groups. RESULTS: 196 patients were identified (25 [12.8%] with GRA use). GRA patients were younger (55.5 vs. 65.3 years, p < 0.001), had higher body mass index (BMI) (34.9 vs. 31.0, p = 0.003), and less commonly had Medicare insurance (4% vs. 40.4%, p = 0.001). GRA patients had fewer levels fused (1.08 vs. 1.88, p < 0.001) and shorter length of stay (LOS) (2.10 vs. 3.13 days, p < 0.001). All other outcomes were similar between groups. 1-year postoperative Oswestry Disability Index (ODI) was better in the GRA group (10.0 vs. 22.2, p = 0.014). Similarly, GRA patients experienced greater improvement in VAS Back at 3-months (-5.75 vs. -3.25, p < 0.001) and 6-months (-5.75 vs. -3.12, p = 0.006), and greater improvement in ODI at 6-months (-44.40 vs. -22.20, p = 0.009) and 1-year (-44.40 vs. -23.49, p = 0.033). Multivariable regression demonstrated that LOS (b = 2.60, p = 0.003) and preoperative ODI (b = 0.41, 95% CI 0.26–0.55, p < 0.001) were independent predictors of 1-year ODI. CONCLUSION: Taking GRAs for weight-loss did not impact safety or postoperative outcomes after lumbar fusion. Although bivariate analysis indicated that GRAs may be associated with superior ODI improvement at 1-year, multivariable regression showed this as independently attributable only to baseline ODI and LOS. Further research is needed to contextualize these findings.