Subcortical hyperintensities on magnetic resonance imaging in patients with severe depression--a longitudinal evaluation.

In a longitudinal evaluation of 37 patients with severe depression who had undergone brain magnetic resonance imaging (MRI) 6 months-2 years (mean 14.1 months) previously, the degree of residual dysfunction was predicted by the extent of subcortical white matter hyperintensities (WMHS, p <.01), longer time elapsed since the MRI scan (p < .05), older age (p < .05), and older age at onset of affective disorder (p < .05). Ten (27%) patients developed "probable" dementia syndromes of the vascular type, with such syndromes being predicted by WMHS (p <.01) and alder age of onset of affective disorder (p <.05). Institutionalization of patients was predicted largely by the combination of chronic depression, progressive cognitive decline, and advanced age. The study supports the notion that a subgroup of patients with late-onset depressive disorders, without a family history of depression, and with risk factors to cerebrovascular disease, have extensive WMHS on MRI, and that such structural brain changes predispose to chronic depression and progressive cognitive decline. (C) 1997 Society of Biological Psychiatry.