Exploring social vulnerability in National Health Safety Network surgical site infections.

Objective: To assess the association between social vulnerability index (SVI) and surgical site infections (SSIs) using National Healthcare Safety Network (NHSN) criteria.

Design: Retrospective cohort study between August 1, 2022, and August 31, 2023.

Setting: In total, 20 acute care hospitals in the Southeast United States.

Patients: Totally, 23,768 total hip arthroplasty, total knee arthroplasty, abdominal hysterectomy, colon, and spinal fusion surgeries in 22,239 patients were included. Procedures with infection present at the time of surgery or incomplete geographic tracking data were excluded.

Methods: Patient addresses as noted in the electronic health record were geocoded to determine census tract of residence and determine SVI. Demographic and clinical data were linked with SVI scores. SSIs were identified according to NHSN criteria. SVI was categorized into quartiles, and logistic regression was used to evaluate the association between SVI quartile (overall and for each SVI theme) and SSI risk. Subgroup analyses by procedure type and race were performed. Multivariable models of the association between overall SVI and SSI were adjusted for demographic and clinical factors.

Results: Patients in the top SVI quartiles had significantly higher odds of developing SSIs after adjusting for other clinical and demographic factors. Increased risk was found for socioeconomic status and household characteristics themes, but not for the racial/ethnic minority theme. Association between SVI and SSI risk varied by type of surgery.

Conclusions: Living in an area with a higher SVI is associated with increased SSI risk. Targeted interventions are needed to mitigate these disparities and improve outcomes.