PURPOSE: Both glucagon-like peptide-1 (GLP-1) receptor agonists and bariatric surgery (BS) are interventions that result in weight loss prior to total knee arthroplasty (TKA). We sought to compare 90-day postoperative complications between TKA patients with a history of GLP-1 use versus those who underwent BS prior to TKA.
METHODS: Patients undergoing primary TKA for osteoarthritis from 2005 to 2025 were identified from the TriNetX Research Network. Patients who underwent BS 6 months to 1 year prior to TKA were propensity score-matched 1:1 to patients who initiated GLP-1 therapy during this same time period based on age, sex, race, chronic kidney disease, rheumatoid arthritis, hypertension, heart disease, diabetes and body mass index (BMI) measured 6 weeks prior to weight-loss intervention. A total of 1650 patients were included in each cohort with 90-day follow-up. The risk of various 90-day complications associated with each weight-loss intervention was compared utilizing univariate analyses.
RESULTS: Rates of individual medical and surgical complications were largely comparable between cohorts; however, compared with the BS group, the GLP-1 cohort had significantly lower rates of deep vein thrombosis/pulmonary embolus (2.18% vs. 4.42%, p < 0.001), transfusion (0.30% vs. 1.03%, p = 0.016), any surgical complication (1.64% vs. 3.45%, p = 0.001), any medical complication (9.09% vs. 12.30%, p = 0.003) and readmission/emergency department visit (21.33% vs. 25.33%, p = 0.007). Compared to obese controls without intervention prior to TKA, both the BS and GLP-1 cohorts had comparable rates of all medical and surgical complications.
CONCLUSIONS: There were largely comparable rates of complications between patients who underwent BS and those who initiated GLP-1 agonists prior to TKA, although GLP-1 use was associated with lower rates of select complications. Patients who choose GLP-1 agonists or BS can expect similar complication rates and comparable outcomes relative to obese patients who elect for no preoperative intervention prior to TKA.
LEVEL OF EVIDENCE: Level III, retrospective cohort study.
