A component-based analysis of metabolic syndrome’s impact on 30-day outcomes after hip fracture: reduced mortality in obese patients

Abstract

Introduction: Hip fractures are a common injury associated with significant morbidity and mortality. In the United States, there has been a rapid increase in the prevalence of metabolic syndrome (MetS), a condition comprised several common comorbidities, including obesity, diabetes mellitus, and hypertension, that may worsen perioperative outcomes. This article assesses the impact of MetS and its components on outcomes after hip fracture surgery. Methods: Patients who underwent nonelective operative treatment for traumatic hip fractures were identified in the 2015–2020 American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database. Baseline characteristics between groups were compared, and significant differences were included as covariates. Multivariate regression was performed to assess the impact of characteristics of interest on postoperative outcomes. Patients with MetS, or a single one of its constitutive components—hypertension, diabetes, and obesity—were compared with metabolically healthy cohorts. Results: In total 95,338 patients were included. Patients with MetS had increased complications (OR 1.509; P, 0.001), but reduced mortality (OR 0.71; P, 0.001). Obesity alone was also associated with increased complications (OR 1.14; P, 0.001) and reduced mortality (OR 0.736; P, 0.001). Both hypertension and diabetes alone increased complications (P, 0.001) but had no impact on mortality. Patients with MetS did, however, have greater odds of adverse discharge (OR 1.516; P, 0.001), extended hospital stays (OR 1.18; P, 0.001), and reoperation (OR 1.297; P 5 0.003), but no significant difference in readmission rate. Conclusion: Patients with MetS had increased complications but decreased mortality. Our component-based analysis showed had obesity had a similar effect: increased complications but lower mortality. These results may help surgeons preoperatively counsel patients with hip fracture about their postoperative risks.