The association between the area deprivation index and dementia in a Veteran Population

Abstract

AbstractBackgroundResidence in a disadvantaged neighborhood is associated with adverse health exposures and outcomes, and may increase risk for cognitive impairment and dementia. We investigated the association of the area deprivation index (ADI) with dementia in in a sample of the national Veteran population.MethodsWe examined data from the Veterans Health Administration (VHA), the largest integrated health care system in the United States. We studied 1,613,337 patients who obtained VHA care from 10/1/1999 to 9/30/2021, (n = 1,395,872 White; n = 147,530 Black) aged ≥55 years (mean: 68.6, SD: 7.7), 98% male. We characterized neighborhood deprivation with the ADI, a validated measure that combines 17 specific indicators (e.g., income, education, employment and housing) into an index of disadvantage. Participant zip codes from residential addresses were geocoded and assigned an ADI national rank according to their census block group. We used these data to categorize participants into ADI rank quintiles, where higher ADI rank quintile corresponds with more deprivation. We estimated adjusted incidence rates of dementia (International Classification of Diseases, 9th and 10th Edition codes) using Cox proportional hazards regression with age as the time scale.ResultsDuring a mean follow‐up of up to 11 (SD 4.8) years, 208,909 participants (12.8%) developed dementia. Compared to the least disadvantaged neighborhood quintile, all other groups had an increased risk of developing dementia in models adjusted for sex, race/ ethnicity, and psychiatric and medical comorbidities. The association was dose‐dependent, with the most disadvantaged quintile demonstrating the greatest risk (Quintile 2 HR: 1.09 95% CI: 1.07, 1.11; Quintile 3 HR: 1.14, 95% CI: 1.12, 1.16; Quintile 4 HR: 1.17, 95% CI: 1.16, 1.19, Quintile 5 HR: 1.24, 95% CI: 1.22, 1.26, Quintile 1 reference group). Repeating our main analysis using competing risks regression led to similar results.ConclusionWe found a dose‐dependent association between ADI and dementia The ADI may be a valuable tool for identifying high‐risk communities for dementia intervention.