GLP-1’s improve cervical fusion rates.

But wait there’s more. GLP-1s continue to bring miracles.

The new study, “Fusion Outcomes of GLP-1 Agonist Therapy in Multilevel Cervical Spinal Fusion: A Propensity-Matched Analysis” (Vatsia et al., PMID: 40042198), dives into the impact of GLP-1 agonist therapy on pseudarthrosis rates in multilevel cervical spine fusion. Given the growing use of GLP-1 agonists like semaglutide and liraglutide for managing obesity and diabetes—conditions often seen in our patient population—this retrospective analysis is highly relevant to the fusion space.

PubMed article – Fusion Outcomes of GLP-1 Agonist Therapy in Multilevel Cervical Spinal Fusion: A Propensity-Matched Analysis

Using the TriNetX Diamond Network database, the authors pulled data from 2005 to 2024, focusing on patients undergoing anterior and posterior multilevel cervical fusions (identified via CPT codes). They split the cohort into two groups: those prescribed GLP-1 agonists (e.g., liraglutide, tirzepatide, dulaglutide) within a year of surgery and those who weren’t. To control for confounders, they propensity-matched the groups based on age, sex, race, nicotine use, BMI, and HbA1c—key variables we know influence fusion outcomes. Pseudarthrosis was tracked using CPT diagnosis codes at 6 months, 1 year, and 2 years post-op, with statistical significance set at P<0.05 and analyzed via Fisher’s exact test.

The results are compelling. For anterior fusions, the GLP-1 cohort (n=1204) showed significantly lower pseudarthrosis rates compared to the non-GLP-1 cohort (n=1204): 10.71% vs. 17.61% at 6 months, 12.04% vs. 18.52% at 1 year, and 12.87% vs. 19.19% at 2 years (all P<0.001). Posterior fusions followed a similar trend (n=1378 per group): 13.21% vs. 22.28% at 6 months, 14.37% vs. 24.45% at 1 year, and 16.87% vs. 24.43% at 2 years (all P<0.001). These reductions are substantial and consistent across timepoints.

From a mechanistic standpoint, the authors suggest GLP-1 agonists may enhance osteoblastic activity and suppress osteoclasts, promoting bone formation and reducing resorption—potentially a game-changer for fusion biology. For those of us in the spine device industry, this could shift how we think about adjunctive therapies alongside our implants. Lower pseudarthrosis rates could mean better outcomes for multilevel constructs, where nonunion risk is already a challenge. It’s not a stretch to see this sparking interest in combo approaches—say, pairing GLP-1 agonists with next-gen biologics or fusion hardware.

The study’s implications are clear: GLP-1 agonists might improve fusion success, particularly in complex cervical cases. That said, it’s retrospective, so we’d need prospective trials to confirm causality and dive deeper into the bone metabolism angle. Still, this could be a signal worth watching—maybe even a nudge to collaborate with pharma on optimizing patient prep or post-op protocols. Thoughts on how this might integrate with current cervical systems or influence future designs?