Key points Is there a difference in the incidence of dementia among Veterans Health Administration enrollees by neighborhood disadvantage as assessed by the Area Deprivation Index (ADI)? Findings In this cohort study of 1,637,484 Veterans Health Administration patients, over a mean follow-up of 11 years, 12.8% of veterans developed dementia; those in the most disadvantaged groups had a higher risk of dementia in models adjusted for demographic characteristics and comorbid conditions, with those residing within the most disadvantaged neighborhood quintile demonstrating the highest risk. Meaning Findings suggest that within a nationally representative cohort of older veterans receiving care, significant differences in dementia incidence existed as a function of neighborhood deprivation. |
Importance
Residence in a disadvantaged neighborhood may be associated with an increased risk of cognitive decline and dementia, but has not been studied in nationally representative populations.
Aim
To investigate the association between the Area Deprivation Index (ADI) and dementia.
Design, environment and participants
Retrospective cohort study within the US Veterans Health Administration from October 1, 1999 to September 30, 2021, with a national cohort of older veterans receiving care in the most integrated health care system. largest of the United States.
For each fiscal year, a random sample of 5% of all patients was selected (n = 2,398,659). Patients with missing information on ADI (n = 492,721) or sex (n = 6) and cases of prevalent dementia (n = 25,379) were excluded. Participants were required to have at least 1 follow-up visit (n = 1,662,863). The final analytical sample was 1,637,484.
Exposed neighborhoods were characterized with the Area Deprivation Index (ADI), which combines several sociodemographic indicators (e.g., income, education, employment, and housing) into a census block group-level disadvantage index. Participants were classified into ADI rank quintiles by their census block group of residence (the highest ADI rank quintile corresponds to more deprivation).
Main result and measures
Time to diagnosis of dementia (using International Classification of Diseases, Ninth Revision and International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes) was estimated with Cox proportional hazards models with age as the rating scale. time, and the sensitivity of the findings were assessed with Fine-Gray proportional hazards models, which account for the competing risk of death.
Results
Among 1,637,484 Veterans Health Administration patients, the mean (SD) age was 68.6 (7.7) years and 198,247 (98.0%) were men. A total of 7,318 patients were Asian (0.4%), 151,818 (9.3%) were black, 10,591 were Hispanic (0.6%), 1,422,713 (86.9%) were white, and 45,044 (2.8%) were white. of other nationalities. or unknown race and ethnicity.
During a mean (SD) follow-up of 11.0 (4.8) years, 12.8% of veterans developed dementia. Compared with veterans in the least disadvantaged neighborhood quintile, those in most disadvantaged groups had a higher risk of dementia in models adjusted for sex, race and ethnicity, and comorbid medical and psychiatric conditions (first quintile = baseline; second quintile ratio adjusted risk ratio [HR], 1.09 [95% CI, 1.07-1.10]; third quintile adjusted HR, 1.14 [95% CI, 1.12-1.15]; fourth quintile, 1.16 [95% CI, 1.14-1.18]; and HR adjusted by fifth quintile, 1.22 [95% CI, 1.21-1.24]). Repeating the main analysis using competing risk of mortality led to similar results.
Conclusions and relevance The results of this study suggest that residence in more disadvantaged neighborhoods was associated with an increased risk of dementia among older veterans integrated into a national health care system. This study demonstrated that neighborhood disadvantage was negatively associated with brain health beyond individual-level factors, even in a population that theoretically has equal access to care. Continued research on the association of neighborhood socioeconomic disadvantage and Alzheimer’s disease and related dementias (ADRD) is needed to understand the potential pathways involved and provide further valuable information for public policy, community interventions, and social and health care. health to prevent and treat ADRD. |
