Psychiatric disorders have no effect on Alzheimer’s risk

Psychiatric disorders do not increase the risk of Alzheimer’s disease, according to new findings.

Researchers from the University of Eastern Finland did, however, see an increased prevalence of psychiatric disorders before an Alzheimer’s diagnosis, which they suspect are early symptoms of the disease. The results were published in the journal European Psychiatry.

“The exponential increase in the prevalence of psychiatric disorders before the diagnosis implies that some of these psychiatric disorders might actually have been prodromal symptoms of Alzheimer’s disease,” the authors write. “This underlines the importance of proper differential diagnostics of Alzheimer’s disease.”

They found a higher risk of Alzheimer’s disease in people who had a history of mood disorder, including depression, or any psychiatric disorder at least five years prior to disease onset. The risk disappeared after 10 years, highlighting the importance of using appropriate time windows to assess risk factors of neurodegenerative diseases with a long onset period. In fact, those risk factors could be manifestations of the neurodegenerative disease.

Researchers analyzed data from the MEDALZ-2005 cohort, which included all Finnish community dwellers with clinically verified Alzheimer’s disease at the end of 2005 and their age, sex and region of residence matched controls.

People with psychiatric disorders diagnosed 10 to 40 years before onset were not found to be at higher risk, but life expectancy for those with psychiatric disorders is still lower. “Thus, those persons with psychiatric disorders who lived long enough to develop Alzheimer’s disease were a selected sample of all persons with psychiatric disorders.”


Topics: Alzheimer's/Dementia