Components of metabolic syndrome as significant risk factors for postoperative complications following total shoulder arthroplasty: hypertension, diabetes, and obesity

Metabolic syndrome (MetS) is a known risk factor for adverse postoperative outcomes. However, the literature surrounding the effects of MetS on orthopedic surgery outcomes following total shoulder arthroplasty (TSA) remains understudied. The purpose of this study is to investigate the effect of MetS on postoperative 30-day adverse outcomes following TSA. The American College of Surgeons National Surgical Quality Improvement Program database was queried for all patients who underwent TSA between 2015 and 2020. After exclusion criteria, patients were divided into MetS and no MetS cohorts. MetS patients were defined as presence of hypertension, diabetes, and body mass index > 30 kg/m 2. Bivariate logistic regression was used to compare patient demographics, comorbidities, and complications. Multivariate logistic regression, adjusted for all significant patient demographics and comorbidities, was used to identify the complications independently associated with MetS. A total of 26,613 patients remained after exclusion criteria, with 23,717 (89.1%) in the no MetS cohort and 2896 (10.9%) in the MetS cohort. On multivariate analysis, MetS was found to be an independent predictor of postoperative pneumonia (odds ratio [OR] 1.61, 95% confidence interval [CI] 1.02-2.55; P  = .042), renal insufficiency (OR 4.09, 95% CI 1.67-10.00; P  = .002), acute renal failure (OR 4.17, 95% CI 1.13-15.31; P  = .032), myocardial infarction (OR 2.11, 95% CI 1.21-3.69; P  = .009), nonhome discharge (OR 1.41, 95% CI 1.24-1.60; P  < .001), and prolonged hospital stay > 3 days (OR 1.44, 95% CI 1.25-1.66; P  < .001). MetS was identified as an independent risk factor for postoperative pneumonia, renal insufficiency, acute renal failure, myocardial infarction, nonhome discharge, and prolonged hospital stay following TSA. These findings encourage physicians to medically optimize MetS patients prior to surgery to limit adverse outcomes.