Brain morphometric abnormalities in geriatric depression: long-term neurobiological effects of illness duration

Objective: The authors' goal was to compare regional brain volumes in depressed elderly subjects with those of nondepressed elderly subjects by using voxel-based morphometry. Method: They used statistical parametric mapping to analyze magnetic resonance imaging scans from 30 depressed patients 59 to 78 years old and 47 nondepressed comparison subjects 55 to 81 years old. Results: Depressed patients had smaller right hippocampal volume than comparison subjects. The volume of the hippocampal-entorhinal cortex was inversely associated with the number of years since the first lifetime episode of depression. Conclusions: These data provide further evidence of structural brain abnormalities in geriatric depression, particularly in patients with a longer course of illness.