Clinical Research Fellow Ohio State University Wexner Medical Center
Disclosure(s):
Muhammad Talal Ibrahim, MD: No financial relationships to disclose
Introduction: Obesity increases the risk of degenerative spine disease and worsens the outcomes of lumbar spine fusion surgery. However, the effect of different BMI groups on surgical outcomes is not linear, and previous literature is either too old, less detailed, or not adjusted for confounders. This study aimed to identify the association between BMI and postoperative complications and perioperative costs in lumbar fusion surgery.
Methods: This study was conducted using the PearlDiver Mariner Database. Patients undergoing index lumbar fusion were divided into five groups based on body mass index (BMI): less than 18.9 (underweight), 19.0 – 24.9 (healthy weight), 25.0 – 29.9 (overweight), 30.0 – 39.9 (Obese-I/II), and more than 40.0 (Obese-III). Patients were followed after 90 and 365 days of surgery. The total patient costs incurred within 90 and 365 days before and after the procedure were also extracted. PearlDiver’s statistical analysis was used for multivariable regression to identify the adjusted odds of complications.
Results: A total of 126,427 patients were included, with most patients in the obese-I/II group (48.2%), followed by the obese-III group (28.9%), and the underweight group (1.8%) had the least patients. The underweight group had the worst outcomes, with lower odds only for lower back pain. Patients in the overweight group had the best outcomes, with lower odds for eight outcomes and higher odds for none. With increasing BMI, the proportion of high odds for complications increased. Notably, the patients with a BMI higher than 25.0 kg/m2 had better neurological outcomes.
Conclusion : Underweight and obese-III patients are at significantly higher odds of surgical complications after lumbar fusion surgery. Overweight and obese-I/II group patients have mixed outcomes. Healthcare-associated costs in the perioperative period were highest for underweight patients, followed by obese-III patients.