Impact of body mass index on 30-day outcomes after spinopelvic fixation surgery

BACKGROUND: Obesity is one of the most prevalent chronic diseases associated with degenerative spinal disease. There is limited evidence regarding the short-term outcome of patients with elevated BMI following spinopelvic fixation surgery. METHODS: We used the American College of Surgeons National Surgical Quality Improvement Program (ACS NSQIP) database from 2013 to 2014. Inclusion criteria included: adults, aged 18 and older, who underwent all-cause spinopelvic fixation surgery. Primary outcome measures were 30-day readmission, reoperation, and major complication rates. Logistic regression analysis was used to assess the effect of elevated body mass index (BMI) on 30-day outcome. RESULTS: A total of 618 patients met inclusion criteria stratified into levels of BMI: 11.2% were Class 2 obese and 10.3% were Class 3 obese. Significant differences were found between the classes for the incidence of revision surgery, reoperations, and deep wound infections. However, there were no significant increases in readmissions and major complications rates, and only Class 3 obese patients had significantly higher odds of reoperation than those who were not obese. CONCLUSION: Significant differences between all classes of obesity regarding revision surgery, reoperation, and deep wound infection rates were found. Class 3 obese patients had significantly higher odds of reoperation, most likely attributed to the greater number/severity of preoperative comorbidities.