Morbid Obesity Increases Length of Surgery in Elective Anterior Cervical Discectomy and Fusion Procedures but Not Readmission or Reoperation Rates: A Cohort Study

Abstract

As the obesity epidemic grows, the number of morbidly obese patients undergoing anterior cervical discectomy and fusion (ACDF) continues to climb. Despite obesity's association with perioperative complications in anterior cervical surgery, morbid obesity's impact on ACDF complications remains controversial, and studies examining morbidly obese cohorts are limited. Single-institution, retrospective analysis of patients undergoing ACDF from September 2010 to February 2022. Demographic, intraoperative, and postoperative data were collected via review of the electronic medical record. Patients were categorized as non-obese [body mass index (BMI) < 30], obese (BMI 30-39.9), or morbidly obese (BMI ≥ 40). The associations of BMI class to discharge disposition, length of surgery, and length of stay (LOS) were assessed using multivariable logistic regression, multivariable linear regression, and negative binomial regression, respectively. A total of 670 patients undergoing single or multilevel ACDF were included, comprised of 413 (61.6%) non-obese, 226 (33.7%) obese, and 31 (4.6%) morbidly obese patients. BMI class was associated with prior history of deep venous thrombosis (p < 0.01), pulmonary thromboembolism (p < 0.05), and diabetes mellitus (p < 0.001). In bivariate analysis, there was no significant association between BMI class and reoperation or readmission rates at 30, 60 or 365 days postoperatively. In multivariable analysis, greater BMI class was associated with increased length of surgery (p = 0.03) but not LOS or discharge disposition. For patients undergoing ACDF, greater BMI class was associated with increased length of surgery but not reoperation rate, readmission rate, LOS, or discharge disposition.