Analyzing the Social Vulnerability Index With Metabolic Surgery

Introduction: The social vulnerability index (SVI) is a census tract-level population-based measure generated from 16 socioeconomic and demographic variables on a scale from 1 (least) to 100 (most) vulnerable. This study has three objectives as follows: 1) to analyze multiple ways of utilizing SVI, 2) compare SVI as a group measure of marginalization to individual markers, and 3) to understand how SVI is associated with choice of surgery in metabolic surgery.

Methods: We retrospectively identified adults undergoing Roux-en-Y gastric bypass and gastric sleeve in 2013-2018 National Surgical Quality Improvement Program data from a single academic center. High SVI was defined as >75^th percentile. Low SVI was coded as <75^th percentile in measure 1 and < 25^th percentile in measure 2. Chi-square and Mann-Whitney U tests were utilized for categorical and continuous variables, respectively. Multivariable regression models were performed comparing SVI to marginalized status as a predictor for type of metabolic surgery.

Results: We identified 436 patients undergoing metabolic surgery, with a low overall morbidity (6.1%). Complication and readmission rates were similar across comparator groups. The logistic regression models had similar area under the curve, supporting SVI as a proxy for individual measures of marginalization.

Conclusions: SVI performed as well as marginalized status in predicting preoperative risk. This suggests the validity of using SVI to identify high risk patients. By providing a single, quantitative score encompassing many social determinants of health, SVI is a useful tool in identifying patients facing the greatest health disparities.