Depressive symptoms and cognitive decline in older african americans: two scales and their factors

Depressive symptoms are common in older adults, and researchers have explored the possibility of a link between depressive symptoms and cognitive decline, with mixed results. Most studies use total score of the Center for Epidemiological Studies Depression Scale (CES-D) with predominately non-Hispanic white participants. We sought to examine the relationship between the four factors of the CES-D and cognitive decline in older African Americans. Generalizability was determined using the Geriatric Depression Scale (GDS) and its factors.

Participants without dementia from the Minority Aging Research Study (N = 298, mean age: 74 ± 5.68) underwent annual clinical evaluations (mean years: 5 ± 1.9), including depression assessment and cognitive testing, from which global and specific measures were derived. Cognitive decline was examined with linear mixed models adjusted for demographic variables and indicators of vascular risk.

Total CES-D score was not related to baseline cognition or change over time, whereas total GDS score was related to decline in semantic and working memory. In examining CES-D factors, lack of positive affect (e.g., anhedonia) was related to decline in global cognition, episodic memory, and perceptual speed. Similarly for the GDS, anhedonia was associated with decline in semantic memory, and increased negative affect was associated with decline in global cognition and episodic, semantic, and working memory.

Results suggest that depressive symptoms, particularly anhedonia and negative affect, are related to cognitive decline in older African Americans.