Neuropsychological functioning and MRI signal hyperintensities in geriatric depression

Objective: The purpose of this study was to examine the relationship betwee n signal hyperintensities-a probable marker of underlying pathology-on T-2- weighted magnetic resonance brain scans and neuropsychological test finding s in elderly depressed and normal subjects. Method: Elderly subjects with a DSM-III-R diagnosis of major depression (N=41) and normal elderly comparis on subjects (N=38) participated in a magnetic resonance imaging study (1.0- T) of signal hyperintensities in periventricular, deep white matter, and su bcortical gray matter. Hard copies of scans were rated in random order by r esearch psychiatrists blind to diagnosis; the modified Fazekas hyperintensi ty rating scale was used. Cognitive performance was independently assessed with a comprehensive neuropsychological battery. Clinical and demographic d ifferences between groups were assessed by t tests and chi-square analysis, Relationships between neuropsychological performance and diagnosis and hyp erintensities and their interaction were analyzed by using analysis of cova riance, with adjustment for age and education. Results: Elderly depressed s ubjects manifested poorer cognitive performance on several tests than norma l comparison subjects. A significant interaction between hyperintensity loc ation/severity and presence/absence of depression on cognitive performance was found: depressed patients with moderate-to-severe deep white matter hyp erintensities demonstrated worse performance on general and delayed recall memory indices, executive functioning and language testing than depressed p atients without such lesions and normal elderly subjects with or without de ep white matter changes. Conclusions: Findings validate cognitive performan ce decrements in geriatric depression and suggest possible neuroanatomic vu lnerabilities to developing particular neuropsychological dysfunction in de pressed subjects.