Introduction: Previous studies have noted an association between obesity and increased risk of complications in idiopathic scoliosis surgery. Few reports have identified an association between complications and obesity in patients following ADS using a large nationwide database. The aim of this study was to analyze whether different grades of obesity influence complication rates in patients undergoing ADS.
Methods: Adult patients (>18 years) undergoing ADS (anterior fusion 2+ levels and/or posterior fusion 6+ levels) were categorized into four BMI groups: non-obese (18.5-29.9 kg/m2), Obese I (30-34.9 kg/m2), Obese II (35-39.9 kg/m2) and Obese III (=40 kg/m2). Obese I to III patients were compared to non-obese patients using chi-square test and analysis of variance. Multivariate logistic regression models were employed to adjust for preoperative risk factors.
Results: 4,716 patients underwent ADS during the study period, with no significant differences between the groups in terms of patient demographics or surgical variables. Among all groups, 24.3% were in the Obese I group, 11.7% Obese II and 6.6% Obese III. Using multivariate analysis only the patients in the Obese III group had a statistically increased risk of UTI (OR 2.8, 95% CI 1.5-5.2, p<0.001), return to OR within 30 days (OR 2.2, 95% CI 1.3-3.7, p=0.002) and increase risk of any complication (OR 1.4, 95% CI 1.1-1.9, p=0.014).
Conclusions: Obese III patients appear to have substantially increased complication rates following ADS. However, they do not appear to be at increased risk of postoperative mortality. Surgeons should be aware of the increased risk of multiple postoperative complications for patients with BMI >40 kg/m2.
Patient Care: To improve patient care, surgeons and spine care providers should be aware of the increased risk of postoperative complications for patients with BMI >40 kg/m2.
Learning Objectives: The aim of this study was to analyze whether different grades of obesity influence complication rates in patients undergoing ADS.