Environmental and social injustices impact dementia risk among older adults with end-stage kidney disease: a national registry study.

Abstract

Racial/ethnic dementia disparities among older adults with end-stage kidney disease (ESKD) are likely driven by environmental and social injustices. We quantified the impact of fine particulate air pollution exposure (PM_2.5; environmental injustice) by racial/ethnic segregation (social injustice) on dementia diagnosis in ESKD. We leveraged the US national registry to identify 884 950 older adults (age ≥55 years) who initiated dialysis (2003-2019). Adjusted Cox regression models with shared state-level frailty quantified the adjusted hazard ratio (aHR) of dementia by PM_2.5 concentrations (annualized and matched to older adults' residential ZIP code at dialysis initiation) and by segregation scores (Theil's H method). Older ESKD adults residing in neighborhoods with high PM_2.5 (n = 598,778, 59,515 with dementia) experienced a 1.44-fold (95% confidence interval (CI):1.41-1.47) higher risk of dementia; this association differed by race and ethnicity (P_interaction<0.0001). Dementia risk was exacerbated for those residing in neighborhoods with high PM_2.5 and segregation (n = 232,708, 29,959 with dementia; aHR = 2.28, 95% CI: 2.21-2.36). Within these neighborhoods, older adults in predominantly minority neighborhoods (aHR = 2.85, 95% CI: 2.75-2.95) had a significantly higher risk of dementia compared to those in neighborhoods with low PM_2.5 and segregation. Older adults with ESKD in neighborhoods with high PM_2.5 experienced an increased risk of dementia; this risk was particularly pronounced among individuals in high segregation and predominantly minority neighborhoods. Environmental and social injustices likely drive racial and ethnic disparities in dementia for older adults with ESKD, underscoring the need for interventions and policies to mitigate these injustices. National Institutes of Health.