Prior bariatric surgery is associated with lower complications, in-hospital mortality and healthcare utilization following elective spine fusion surgery

Abstract Background Grade 3 obesity could potentially increase postoperative complications following spinal fusion surgery. However, the relationship between prior bariatric surgery (prior-BS) and postoperative complications following spinal fusion surgery is not well-established. Setting Inpatient hospital admissions from the Nationwide Inpatient Sample. Methods Patients with a primary procedure of spinal fusion surgery discharged between 2006 and 2014 were identified. In-hospital outcomes included postoperative complications, mortality, cost and length of stay (LOS) were compared between patients with prior BS and grade 3 obesity. Results A total of 3,132,192 patients who underwent elective spinal fusion surgery were identified. There were 33,936 (1.1%) patients with a diagnosis of prior BS. The prevalence of prior-BS increased significantly from 0.1% in 2006 to 1.5% in 2014. Compared to patients with grade 3 obesity, patients with prior-BS were younger, more likely to be female, had less comorbidities and higher proportion of cervical surgery. Multivariable analysis indicated that patients with prior-BS had lower risk of overall complications (OR: 0.44; 95% CI:0.38-0.49), neurologic (OR:0.55; 95%CI: 0.35-0.84), respiratory (OR:0.30; 95%CI: 0.23-0.37), cardiac (OR:0.38; 95%CI: 0.24-0.60), gastrointestinal (OR:0.61; 95%CI: 0.44-0.84), urinary and renal (OR:0.34; 95%CI: 0.26-0.44), venous thromboembolism (OR:0.35; 95%CI: 0.19-0.63), wound-related complications (OR:0.67; 95%CI: 0.53-0.85) and in-hospital mortality (OR:0.12; 95%CI: 0.02-0.88). Prior-BS was also related to 13% shorter LOS and 2% lower cost. Conclusions Among patients undergoing spinal fusion surgery, prior-BS is associated with lower complications, in-hospital mortality and healthcare utilization. Bariatric surgery might mitigate risk of worse outcomes associated with grade 3 obesity following spine fusion surgery.