Impact of Obesity on Outcomes in Adults Undergoing Elective Posterior Cervical Fusion

Study Design: Retrospective study of prospectively collected data.

Objective: To determine the effect of obesity (body mass Index > 30) on postoperative morbidity and mortality after elective posterior cervical fusion in adults.

Summary Of Background Data: In those with spine disease, obesity has been shown to portend poorer general and disease-specific functional health status. The effect of obesity on outcomes after spine surgery, especially posterior cervical fusion, however, remains unclear. Previous studies have been contradictory to one another and largely limited by small sample sizes.

Methods: The American College of Surgeons National Surgical Quality Improvement Program is a large multicenter clinical registry that prospectively collects preoperative risk factors, intraoperative variables, and 30-day postoperative morbidity and mortality outcomes from about 400 hospitals nationwide. Current Procedural Terminology codes were used to query the database for adults who underwent posterior cervical fusion between 2005 and 2012. Patients were separated into cohorts based on obesity status. Univariate analysis and multivariate logistic regression were used to analyze the effect of obesity on postoperative morbidity and mortality.

Results: There was a significantly higher rate of only venous thromboembolism (VTE) in the obese group compared with nonobese cohort (3.5% vs. 0.6%, P = 0.015). On multivariate analysis, obesity was found to be an independent predictor (odds ratio 6.15; 95% confidence interval [CI], 1.26-30.20; P = 0.02) for VTE.

Conclusion: The present study demonstrated that patients with obesity can safely undergo posterior cervical fusion surgery. Although obesity predisposed to an elevated risk of VTE, postoperative mortality and morbidity were otherwise not significantly increased in this population.

Level Of Evidence: 3.