Moving from Scores to Solutions: Lessons Learned from the Social Vulnerability Index and Disparities in Surgical Outcomes

Social vulnerability index (SVI) is a composite measure of 16 census tract-level variables from the American Community Survey that are categorized into four domains: socioeconomic status, household composition, language and minority status, and housing and transportation.¹ SVI was developed by the U.S. Centers for Disease Control and Prevention in 2011 for resource allocation in response to natural or human disasters.² The vulnerability of a neighborhood is scored on a scale that ranges from 0 - 100, representing low to high vulnerability. Since its creation, SVI has been widely incorporated into clinical research for assessment of social deprivation. The surgical literature has leveraged SVI to evaluate health disparities, and high SVI has been found to be associated with undesirable surgical outcomes. For example, patients from areas with high SVI have worse long-term outcomes after traumatic injury and are more likely to undergo emergent versus elective cholecystectomy and colectomy compared to their counterparts with low SVI.^3-5

In this issue of American Journal of Surgery, Dyas et al. report surgical outcomes based on SVI using the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) data from five hospitals within one regional care network in Colorado.⁶ In this comprehensive analysis that included 31,224 patients who underwent surgery across multiple surgical sub-specialties, high SVI (defined as score ≥ 75) was associated with younger age, female sex, self-identification as a racial/ethnic minority, and higher comorbidity severity. Despite similar case complexity between the low and high SVI groups as highlighted by similar mean work relative value units (wRVU) between the two populations, patients with high SVI experienced more surgical complications (including infections, cardiac and respiratory complications), and higher rates of non-home discharge and unplanned re-admissions after surgery. These post-operative occurrences were common among patients with high SVI who underwent general, gynecologic, and orthopedic surgeries.

Although numerous studies have found that barriers associated with social determinants of health (SDOH) negatively impact surgical outcomes, this study by Dyas et al. adds to the literature by evaluating SVI in a broad surgical population. One strength of the analysis includes the comprehensive approach that was used to assess surgical outcomes in several surgical sub-specialties based on patient SVI. The authors provided a comprehensive summary of complications that were likely to be experienced by patients from vulnerable communities, and they suggested strategies such as aggressive urinary catheter removal protocols and extensive pre-operative cardiac work-up that could mitigate poor outcomes in this population. One limitation is that more than 80% of patients were White. Thus, these results may not generalize to other regions in the U.S.

These findings amplify the existing literature regarding adverse health consequences that patients from socially vulnerable communities experience in the U.S. healthcare system. Policies addressing structural SDOH at the neighborhood level would help to promote health equity among surgical patients. One approach that could support development of new policies is utilization of the Healthy People 2030 framework as a guide. This framework divides SDOH into five domains including education access, healthcare access, neighborhood and built environment, social and community context, and economic stability.⁷ From a clinical perspective, measures to identify socially vulnerable patients who are presenting for surgery in a timely fashion to mitigate undesirable outcomes is essential. This could be addressed through the incorporation of SVI data into surgical risk estimation tools to help with prediction of surgical outcomes. Implementation of this approach could prompt surgical teams to take extra measures to optimize pre-operative comorbidities and key post-operative care elements of patients with high SVI. If we are going to achieve health equity in the U.S. (i.e., elimination of health disparities and their determinants), clinicians, researchers, and public policymakers must work together to identify solutions.