Depression and Cognitive Decline in the Elderly: A Follow-up Study

Thirty-five depressed elderly subjects, who received comprehensive evaluations in a memory disorders clinic, were followed (mean of 24 months) and evaluated with a brief neuropsychological battery. Diagnoses were made by consensus of a board-certified neuropsychologist and neurologist. A deterioration of four points on follow-up Folstein MMSE, compared to initial MMSE (based on calculation of the standard error of difference), defined cognitive decline. Eight patients demonstrated cognitive decline and 27 did not. A MANOVA using initial neuropsychological, depression severity, and demographic variables did not differentiate the two groups. Chi-square analyses on medical and radiological data from the initial examination showed that those depressed subjects with decline had a greater number of abnormal MRIs, CTs, and EKGs. Results from MRI and CT demonstrated the presence of leukoaraiosis in the depressed patients with cognitive decline. Leukoaraiosis in some depressed elderly may contribute to their cognitive decline and dysphoric affect. Further, depression in some elderly may present the first sign of a later developing dementia.