Friday, September 28, 2018 3:00 PM–4:00 PM abstracts: the gravity of obesity: 226. Prior bariatric surgery lowers complication rates following spine surgery in obese patients

Abstract

BACKGROUND CONTEXT Bariatric surgery is an increasingly common treatment for morbid obesity that has the potential to effect bone and mineral metabolism. The effect of prior bariatric surgery on outcomes following spinal surgery has not been well-established. PURPOSE To assess differences in complication rates following spinal surgery for patients with and without a history of bariatric surgery. STUDY DESIGN/SETTING Retrospective analysis of the prospectively collected New York State Inpatient Database (NYSID) years (2004–2013). PATIENT SAMPLE A total of 1,939 patients with prior bariatric surgery now undergoing spine surgery, 1,625 overweight or obese spine surgery patients (no bariatric procedures), and 28,304 spine surgery patients who are not obese or overweight. OUTCOME MEASURES Complications following spine surgery. METHODS Retrospective analysis of the prospectively collected New York State Inpatient Database (NYSID) years 2004-2013. Patient linkage codes allow identification of multiple and return inpatient stays within the time-frame analyzed. Complication rates were compared between bariatric surgery patients now undergoing spine surgery versus morbidly obese patients having spine surgery. Bariatric surgery (BS) patients and morbidly obese patients (non-BS) were divided into cervical and thoracolumbar surgical groups and were propensity score matched for age, gender and degree of invasiveness. Nonobese spine surgery patients were used as a standard. RESULTS A total of 1,939 spine surgery patients with a history of BS were compared to 1,625 non-BS spine surgery patients in the NYSID database. A total of 89% of normal weight spine surgery patients had a decompression and the overall complication rate for these patients is 45%. The average time from bariatric surgery to spine surgery is 2.95 years. BS patients had primarily two-three level fusions and decompressions, which is similar to non-BS patients. After propensity score matching for age, gender and invasiveness, 740 BS patients were compared to 740 non-BS patients undergoing thoracolumbar surgery, with similar comorbidity rates between cohorts. The overall complication rate for BS patients undergoing thoracolumbar surgery was significantly lower than non-BS patients (45.8% vs. 58.1%, P .05). CONCLUSIONS Bariatric surgery patients undergoing spine surgery experience lower overall complication rates than morbidly obese patients. This study warrants further investigation into these populations to mitigate risks associated with spine surgery for bariatric patients.