Abstract
BACKGROUND: Individual- and neighborhood-level social determinants of health (SDOH) measures have been associated with higher incidence of acute kidney injury (AKI), lower likelihood of recovery, and higher risk of mortality following AKI. The association of SDOH measures with post-hospitalization AKI follow-up care is unknown. METHODS: Using a retrospective cohort design, we evaluated the association of individual- (insurance status, race, ethnicity) and neighborhood-level (socioeconomic deprivation, rurality, residential segregation, and social vulnerability to natural or human-caused disasters) SDOH measures with receipt of post-hospitalization follow-up for AKI within three months of hospital discharge among intensive care unit (ICU) survivors with AKI stage 2 or 3 hospitalized between 2012 and 2023 at a major academic medical center. The primary outcome, post-hospitalization AKI follow-up, was defined as the occurrence of at least one of the following within three months of hospital discharge: a nephrology outpatient visit, serum creatinine measurement, or urine protein measurement. We utilized pooled logistic regression models with inverse probability of censoring weighting to adjust for demographics, comorbidities, and hospitalization characteristics and to account for the competing risks of death, re-hospitalization, or dialysis initiation. RESULTS: Among 13,392 adult ICU survivors with AKI stages 2 or 3, 5,970 (45%) were female, 4,488 (34%) were of Black race, and 1,561 (12%) were uninsured. A total of 7,316 (61%) received post-hospitalization follow-up for AKI within three months of hospital discharge. Uninsured individuals (adjusted odds ratio (aOR) 0.77, 95% confidence interval (CI) 0.70–0.84), individuals residing in a neighborhood with greater socioeconomic deprivation (aOR 0.86, 95% CI 0.81–0.92), greater rurality (aOR 0.86, 95% CI 0.81–0.92), greater segregation (aOR 0.92, 95% CI 0.87–0.98), and greater social vulnerability (aOR 0.83, 95% CI 0.77–0.89) all experienced significantly lower odds of post-hospitalization AKI care. CONCLUSIONS: Both individual- and neighborhood-level SDOH were associated with lower odds of post-AKI follow-up among ICU survivors with severe AKI.