Metabolic Syndrome and 30-Day Outcomes in Elective Lumbar Spinal Fusion

Study Design. A retrospective cohort study. Objective. The aim of this study was to evaluate the effect of metabolic syndrome (MetS) on 30-day morbidity and mortality following elective lumbar spinal fusion. Summary of Background Data. MetS is a variable combination of hypertension, obesity, elevated fasting plasma glucose, and dyslipidemia. MetS has been associated with an increased risk of postoperative morbidity and mortality in multiple surgical settings. To our knowledge, the effect of MetS on 30-day outcomes following elective lumbar spinal fusion has not been well studied. Methods. An analysis of ACS-NSQIP data was performed between 2006 and 2013. Patients undergoing elective posterior lumbar fusion were identified. Emergency procedures, infections, tumor cases, and revision surgeries were excluded. Patients were defined as having MetS if they had a history of hypertension requiring medication, diabetes, and a body mass index (BMI) >= 30 kg/m(2). Results. One thousand five hundred ninety (10.2%) patients with MetS were identified. A mild increase in major (P = 0.040) and minor complications (P = 0.003) in patients with MetS was noted. MetS was associated with increased rates of pulmonary complications (1.9% compared with 1.0%; P = 0.001), sepsis (1.7% compared with 0.9%; P = 0.005), and acute post-op renal failure (0.4% compared with 0%; P < 0.001). Multivariate analysis confirmed MetS to be an independent predictor of pulmonary complications [odds ratio (OR) 1.51; 95% confidence interval 95% CI 1.00-2.27); P = 0.048], sepsis (OR 1.56; 95% CI 1.01-2.42; P = 0.039), and acute postoperative renal failure (OR 6.95; 95% CI 2.23-21.67; P = 0.001). MetS status was associated with a mild increase in total hospital length of stay (4.38 compared with 3.81 days; P < 0.001). Conclusion. While MetS is a predictor of postoperative acute renal failure, it only slightly increases the risk of overall complications and is not associated with increased rates of 30-day reoperations or readmissions following elective lumbar fusion.