Persistence of neuropsychologic deficits in the remitted state of late-life depression.
OBJECTIVE: Cognitive impairment in late-life depression (LLD) is prevalent, disabling, and persists despite the remission of depressive symptoms. This article characterizes neuropsychologic functioning during remission in LLD. METHODS: The authors examined longitudinal performance on a comprehensive neuropsychologic battery in 56 nondemented subjects age 60 or older who initially presented with an episode of nonpsychotic unipolar major depression and 40 nondemented, age- and education-equated comparison subjects with no history of depression. Subjects were assessed at baseline (in a depressed state) and one year later (when remitted). RESULTS: After one year, 45% of the LLD subjects were cognitively impaired despite remission of depression. Visuospatial ability, information-processing speed, and delayed memory were most frequently impaired; 94% of the patients who were impaired at baseline remained impaired one year later. Twenty-three percent of the patients who were cognitively normal while depressed developed impairment one year later. CONCLUSIONS: Most older individuals who are cognitively impaired during a depressive episode remain impaired when their depression remits. In addition, a substantial proportion of older depressed individuals who are cognitively intact when depressed are likely to be impaired one year later, although their depression has remitted.