Association of 1-year change in neuroticism and 3-year change in cognitive performance among older depressed adults

The relationships among depression, personality factors, and cognitive decline in the elderly are complex. Depressed elders score higher in neuroticism than nondepressed older individuals. Presence of neuroticism worsens cognitive decline in depressed older adults. Yet little is known about changes in neuroticism among older adults being treated for depression and the impact of these changes on cognitive decline.

Longitudinal observational study.

Academic Health Center.

We examined 68 participants in the neurobiology of late-life depression (LLD) study to test the hypothesis that older depressed subjects with more improvement in neuroticism would experience less cognitive decline compared with those with less change in neuroticism.

We measured neuroticism using the NEO-Personality Inventory-Revised at baseline and 1 year. Study psychiatrists measured depression using the Montgomery-Åsberg depression rating scale (MADRS). Global cognitive performance was measured using the Consortium to Establish a Registry for Alzheimer's disease (CERAD) battery at baseline and annually over 3 years. Regression models of 1-year change in neuroticism and 3-year change in CERAD included sex, age, race, education, and 1-year change in MADRS score as covariates.

We found that among older adults, 1-year change in neuroticism was inversely associated with 3-year change in CERAD total score.

Our findings challenge the notion of longitudinal stability of measures of personality, especially among older depressed individuals. They highlight the importance of repeated personality assessment, especially of neuroticism, in the management of LLD. Future studies in larger samples followed for longer periods are needed to confirm our results and to extend them to examine both cognitive change and development of dementia.