Link between LLD & Dementia Risk

Late-life depression and risk of vascular dementia and Alzheimer?s disease: a systematic review and meta-analysis of community-based cohort studies.

Diniz BS, Butters MA, Albert SM, Dew MA, Reynolds CF

Late-life depression is one of the most common psychiatric illnesses in older adults, affecting 15% of adults aged 65 or older in the United States (approximately 6 million people). Previous studies have shown an association between depression and Alzheimer's disease, but a study by investigators in Pitt's Department of Psychiatry, including Drs. Meryl Butters, Mary Amanda Dew, and Charles Reynolds, is the first meta-analysis that specifically addresses the risk of Alzheimer's disease and vascular dementia in older adults with late-life depression. The study, published in the British Journal of Psychiatry, is also the first to show that late-life depression increases the risk of vascular dementia and that the risk of vascular dementia is greater than the risk of Alzheimer's disease for older adults with depression.

The meta-analysis involved the evaluation of 23 community-based cohort studies in order to calculate the pooled risk of all-cause dementia, Alzheimer's disease, and vascular dementia in older adults with late-life depression. The findings concluded that those with late-life depression are: 1) 1.85 times more likely to develop all-cause dementia; 2) 1.65 times more likely to develop Alzheimer?s disease; and 3) 2.52 times more likely to develop vascular dementia.

An understanding of how late-life depression increases the risk of dementia could lead to better prediction and prevention mechanisms. Early diagnosis and prevention of depression could have a major dual public health impact as they could also potentially prevent or delay cognitive decline and dementia in older adults. Using these findings, clinical trials can be conducted to investigate the impact of preventing depression on risk of cognitive decline and dementia in older adults.

Contributors:
Meryl A. Butters, PhD; Mary Amanda Dew, PhD; Charles F. Reynolds, MD (Department of Psychiatry, University of Pittsburgh)
Breno S. Diniz, MD (Department of Mental Health, School of Medicine, Federal University of Minas Gerais, Brazil)
Steven M. Albert (Department of Behavioral and Community Health Sciences, University of Pittsburgh Graduate School of Public Health)

The results of this investigation were published in the May 2013 issue of the British Journal of Psychiatry. Click here for a link to the abstract.  This publication was selected for F1000 Prime.