IMPACT OF GLP-1 AGONISTS AND SOCIAL DETERMINANTS OF HEALTH ON OUTCOMES FOLLOWING TOTAL KNEE ARTHROPLASTY

Abstract

Glucagon-like peptide (GLP)-1 agonists are increasingly used for type 2 diabetes and obesity management. Access to GLP-1 medications remains difficult for patients, especially those with low socioeconomic status. GLP-1s have been demonstrated to be predictors of positive outcomes following total knee arthroplasty (TKA), however these findings may be confounded by the presence of social determinants of health (SDOH). The interaction between SDOH and GLP-1 use, with implications on outcomes following TKA, has yet to be explored. We conducted a retrospective cohort study of obese patients (body mass index ≥ 35 kg/m 2 ) undergoing primary TKA using the TriNetX Research Network. GLP-1 medication use was recorded within three months of surgery. 90 day and 2-year outcomes were collected using ICD-10 and CPT codes. Patients undergoing TKA with and without recent GLP-1 use were compared. Cox proportional hazard modeling was used with covariates including unfavorable SDOH ICD-10 codes (Z55-65) and medical comorbidities including biomarkers for diabetes severity. An alpha value of 0.05 was used. 85,465 patients were included, with 3,835 using GLP-1 agonists. SDOH was significant in predicting 90-day readmission (hazard ratio [HR] 1.55, p<0.0001), emergency department presentation (HR 1.8, p<0.0001), and medical complications (HR 1.7, p< 0.0001). Unfavorable SDOH was significant in predicting 2-year periprosthetic fracture risk (HR 1.96, p = 0.03). GLP-1 use was not significant in predicting 2-year prosthetic joint infection, periprosthetic fracture, mechanical loosening, or all cause revision rates. Previous literature has demonstrated positive outcomes for obese patients who were prescribed GLP-1 agonists prior to total knee arthroplasty. Our data suggests that some of these short-term benefits are confounded by SDOH and may not be related to GLP-1 use itself. Further, prospective research is needed to further delineate the biologic effects of GLP-1 agonists from their predilection to be prescribed to higher income groups.