Increased Dementia Incidence among Black and Hispanic Veterans across Regions of the United States

Abstract

AbstractBackgroundAlthough the US military is increasingly diverse, the association of race/ethnicity and geographical region with incidence of dementia diagnosis among older Veterans is unknown.MethodWe identified a random sample of 1,869,090 patients age ≥ 55 years [mean age: 69.4 (standard deviation 7.9), 2% female] who received care at the Veterans Health Administration (VHA), the largest integrated health care system in the United States, between October 1, 1999 and September 30, 2019. Participants self‐reported race/ethnicity: White: 88.6% (n = 1,655,376); Black, 9.5% (n = 176,795); Hispanic (1.0%, n = 20,663), Asian (0.5%, n = 9,391), or American Indian/Alaska Native [AIAN (0.4%, n = 6,895). US region was derived using residential ZIP codes and categorized based on 10 Center for Disease Control and Prevention Health Promotion regions. Incident dementia was defined using International Classification of Diseases, 9th (ICD‐9) and 10th (ICD‐10) edition codes; age‐adjusted dementia incidence was estimated using direct standardization to compare rates by race/ethnicity overall and by US region.ResultOver a mean follow‐up of 10.1 years, 243,272 (13%) participants received a diagnosis of dementia. Age‐adjusted incidence per 1,000 person‐years was 14.2 [95% confidence interval (CI), 13.3‐15.1] for AIAN participants, 12.4 (95% CI, 11.7‐13.1) for Asian participants, 19.4 (95% CI, 19.2‐19.6) for Black participants, 20.7 (95% CI, 20.1‐21.3) for Hispanic participants, and 11.5 (95% CI, 11.4‐11.6) for White participants. Across US regions, a similar pattern was observed; compared to White participants, rates were significantly higher for Black participants across all regions (15.5 to 20.7, p values <0.001), and for Hispanic participants in all regions except the Southeast (14.0 to 21.7, p values ≤ 0.03). Across most regions, AIAN (8.6 to 16.2,) and Asian participants (8.4 to 15.6,) showed a pattern of rates that was similar to or slightly higher than for White participants (9.8 to 12.0, p values >0.05).ConclusionAmong older Veterans receiving care at VHA, where access to care for enrollees is held relatively equal, differences in dementia incidence were observed based on race/ethnicity. Across US regions, rates varied, but incidence was consistently higher for Black and Hispanic Veterans. Further research is needed to elucidate drivers of these differences.