The metabolic syndrome in patients undergoing knee and hip arthroplasty: trends and in-hospital outcomes in the United States.

We evaluated the impact of metabolic syndrome (MetS) on perioperative outcomes in patients undergoing total joint arthroplasty. Using the Nationwide Inpatient Sample, patients with MetS were identified if they had at least 3 of 4 component comorbidities (obesity, dyslipidemia, hypertension, and diabetes). Patient demographics, in-hospital outcomes, and cost were compared between patients with and patients without MetS. Trends were studied for 3-year periods between 2000 and 2008. The prevalence of MetS increased over time, reaching 14% (total knee arthroplasty) and 8.7% (total hip arthroplasty) most recently. Metabolic syndrome was overproportionately prevalent among female total knee arthroplasty recipients, male total hip arthroplasty recipients, and patients in the minority race group. In the regression analysis, MetS was an independent risk factor for the development of major complications, nonroutine discharge, and increased hospital cost. Given the increasing rates of MetS and its association with higher risk for major complications among total joint arthroplasty recipients, further research into the impact of this disease complex is warranted.