Change in hippocampal volume on magnetic resonance imaging and cognitive decline among older depressed and nondepressed subjects in the neurocognitive outcomes of depression in the elderly study.

INTRODUCTION: previous studies have linked hippocampal volume change and cognitive decline in older adults with dementia. The authors examined hippocampal volume change and cognitive change in older nondemented adults with and without major depression.
METHODS: the sample consisted of 90 depressed individuals and 72 healthy, nondepressed individuals aged 60 years and older who completed at least 2 years of follow-up data. All patients underwent periodic clinical evaluation by a geriatric psychiatrist as well as baseline and 2-year magnetic resonance imaging.
RESULTS: over 2 years, the depressed group showed a greater reduction in left hippocampal volume (normalized for total cerebral volume) compared with the nondepressed group (mean difference = 0.013 ± 0.0059, t = 2.18, df = 160, p <0.0305). The difference remained significant after controlling for age, sex, and baseline normalized left hippocampal volume. The authors also found that hippocampal change from baseline to 2 years was associated with subsequent change in Mini-Mental State Examination score from 2 years to 2½ years (left t = 2.81, df = 66, p = 0.0066; right t = 2.40, df = 66, p = 0.0193) among the depressed group.
CONCLUSIONS: these findings add to the literature linking hippocampal volume loss and late-life depression. Depressed patients with hippocampal volume loss are at greater risk of cognitive decline. 2011 American Association for Geriatric Psychiatry.