Impact of Obesity on Surgical Outcomes Following Laminectomy for Spinal Metastases

Study Design: Retrospective cohort study. Objectives: To determine the effect of obesity (body mass index >30 kg/m²) on perioperative morbidity and mortality after surgical decompression of spinal metastases. Methods: The American College of Surgeons National Surgical Quality Improvement Program database is a large multicenter clinical registry that collects preoperative risk factors, intraoperative variables, and 30-day postoperative morbidity and mortality outcomes from hospitals nationwide. Current Procedural Terminology codes were used to query the database for adults who underwent decompression with laminectomy for treatment of metastatic spinal lesions between 2010 and 2014. Patients were separated into 2 cohorts based on the presence of absence of obesity. Univariate analysis and multivariate logistic regression analysis were used to analyze the effect of obesity on perioperative morbidity and mortality. Results: There was a significantly higher rate of venous thromboembolism (VTE; obese 6.6% vs nonobese 4.2%; P =.01) and pulmonary complications (obese 2.6% vs nonobese 2.2%; P =.046) in the obese group compared with the nonobese group. The nonobese group had prolonged hospitalization (obese 62.0% vs nonobese 69.0%; P =.001) and a higher incidence of blood transfusions (obese 26.8% vs nonobese 34.2%; P <.001). On multivariate analysis, obesity was found to be an independent risk factor for VTE (odds ratio = 1.75, confidence interval = 1.17-2.63, P =.007). Conclusions: Obese patients were predisposed to an elevated risk of VTE following laminectomy for spinal metastases. Early postoperative mobilization and a low threshold to evaluate for perioperative VTE are important in these patients in order to appropriately diagnose and treat these complications and minimize morbidity.