Intersecting vulnerabilities: Race, Depression, and White Matter Hyperintensity burden in Aging.

BACKGROUND

White matter hyperintensities (WMHs) are markers of brain aging and are associated with cognitive decline and dementia. However, research regarding how race, ethnicity, and depression status influence WMHs remains mixed. This study examined the interactive effects of race/ethnicity and depression on WMHs and cognition in older adults.

METHODS

Data from the National Alzheimer's Coordinating Center included 2,411 older adults (773 Whites with Depression, 1,360 Whites without Depression, 89 Blacks with depression, 189 Blacks without depression). Bootstrap sampling (1,000 iterations) was used to match the White and Black samples. Linear regressions were then used to i) assess WMH differences across race/ethnicity and depression groups, and ii) to examine whether the associations between WMH burden and cognition were different across these groups.

RESULTS

Black older adults with depression showed greater global as well as regional WMH burden than Black older adults without depression (median = 0.68-1.67), and depression significantly influenced the relationship between WMH burden and cognitive impairment in this group (median = 1.15-2.03). Similar results were observed for Hispanics with depression (median = 1.47-2.87), while WMH burden did not differ in White older adults with and without depression.

CONCLUSIONS

These findings suggest that race and depression may jointly influence cerebrovascular disease burden as well as its associations with cognition in aging and dementia.