Association between limited primary care access and higher readmissions and reoperations following elective lumbar fusion.

Abstract

Lumbar spinal fusion is a common intervention performed for the treatment of degenerative spinal disease. Recent literature has identified disparities in lumbar fusion outcomes relative to socioeconomic status; however, the underlying mechanisms remain unclear. The authors hypothesized that access to primary healthcare services could be significantly associated with increased complications and reoperation rates in patients undergoing elective lumbar fusion. They sought to assess the association of low access to primary healthcare with readmissions, reoperations, and complications following spinal fusion. All adult patients who underwent open and minimally invasive lumbar spine fusion procedures at a single institution between 2011 and 2023 were retrospectively identified using Current Procedural Terminology and ICD-9/-10 codes. Patient addresses underwent geospatial analysis to retrieve census tract codes. Medically underserved area (MUA) designations for census tracts were made according to the Health Resources Services Administration. MUA designation is calculated based on access to primary care services in a designated census tract. Both matched analysis and multivariate analyses were performed to assess the effect of residence in an MUA and other variables on readmission and reoperation rates. A total of 1567 operations were included. The median age at the time of surgery was 64 (56-70) years, and 154 (9.8%) resided in an MUA. In multivariate regression adjusting for clinical and other socioeconomic variables, low access to care was associated with increased odds of 30-day (OR 1.86, 95% CI 1.13-2.97; p = 0.011) and 90-day (OR 1.84, 95% CI 1.20-2.77; p = 0.004) readmissions. After exact matching by age, race, Area Deprivation Index, surgical characteristics, income, and comorbidity burden, patients with low access to care had increased rates of readmission due to surgical complications within 30 days (13% vs 4.6%, p = 0.002) and 90 days (15% vs 7.4%, p = 0.011) and had increased rates of reoperation within 30 days (9.1% vs 3.7%, p = 0.024) and 90 days (12% vs 5.1%, p = 0.015). The authors' results suggest that access to a primary care provider could be an underlying driver of disparities in lumbar fusion surgery complications. Utilization of this novel metric might serve as a useful tool for preoperative risk stratification and represent an opportunity for optimization to minimize unplanned readmissions.