Patterns of late‐life depressive symptoms and subsequent declines in cognitive domains
International Journal of Geriatric Psychiatry
Published online on November 07, 2016
Abstract
Background
Depression frequently co‐occurs with cognitive decline, but the nature of this association is unclear. We examined relations of late‐life depressive symptom patterns to subsequent domain‐specific cognitive changes.
Methods
Depressive symptoms were measured at up to 3 timepoints among 11,675 Nurses' Health Study participants prior to cognitive testing. Depressive symptom patterns were categorized as non‐depressed, variable or persistent, based on published severity cutpoints. Outcomes were global, verbal, and executive function‐attention composite scores.
Results
Participants with persistent depressive symptoms had worse executive function‐attention decline compared with non‐depressed participants (multivariable‐adjusted mean difference = −0.03 units/year, 95% CI: −0.05, −0.01; p = 0.003); this difference was comparable with 8 years of aging. However, being in the persistent versus non‐depressed group was not significantly related to verbal (p = 0.71) or global score (p = 0.09) decline. By contrast, compared with the non‐depressed group, those with variable depressive symptoms had worse verbal memory decline (multivariable‐adjusted mean difference = −0.01 units/year, 95% CI: −0.02, −0.002; p = 0.03); this group showed no differences for global or executive function‐attention decline.
Conclusions
A variable pattern of depressive symptom severity related to subsequent decline in verbal memory, while a persistent pattern related to decline in executive function‐attention. Findings could signal differences in underlying neuropathologic processes among persons with differing depression patterns and late‐life cognitive decline. Copyright © 2016 John Wiley & Sons, Ltd.