Neighborhood socioeconomic disadvantage is not associated with adverse outcomes following elective spine surgery in older Veterans

Background: In the US, over half of all cervical and lumbar arthrodesis spine surgeries are for people ≥60 years of age. The extent to which adverse outcomes vary by social (eg, disadvantaged neighborhoods) and demographic factors have been scarcely investigated in spine surgery. We investigated the association of social, demographic, and clinical factors with complications, 30-day readmission, and 30-day mortality in older Veterans undergoing elective spine surgery. Methods: Veterans (N=5,277) aged ≥65 years who underwent inpatient elective spine surgery for degenerative disease in the Veterans Affairs Surgical Quality Improvement Program (VASQIP) comprised our retrospective cohort. VASQIP (2013–2019) data were merged with other Veterans Health Administration (VHA) and Medicare administrative data. Multivariable logistic regression models were estimated to assess the associations of social (rurality, Area Deprivation Index [ADI]) and clinical (frailty, comorbidity) factors with complications, 30-day readmission, and 30-day mortality. The ADI is a neighborhood-level socioeconomic disadvantage ranking using 17 variables (eg, housing quality). We defined highly disadvantaged as ADI>85. Results: Veterans aged 65–74 years comprised 82.7%; 77.9% identified as White, 15.1% as Black, and 7.0% as another race; and 97.1% were male. Over one-third (38.9%) lived in rural areas and 12.3% lived in highly disadvantaged neighborhoods. Readmission and mortality were 10.0% and 0.6%, respectively, and 6.0% experienced complications. Rurality and ADI>85 were not associated with complications, 30-day readmission, or 30-day mortality. Frailty, comorbidity, class-3 obesity, and operative stress were associated with adverse outcomes. Conclusions: Social (rurality, ADI>85) and demographic variables were not associated with complication, 30-day readmission, or 30-day mortality in older Veterans following elective spine surgery. While clinical factors (frailty, co-morbidity, class-3 obesity, and operative stress score) were associated with adverse outcomes, Veterans in this study did not experience disparities in medical outcomes due to social vulnerability. Untangling mechanisms connecting social and clinical factors may improve outcomes.