Elderly with depression, mild cognitive impairment more vulnerable to accelerated brain aging

August 7, 2014
Credit: George Hodan/Public Domain

People who develop depression and mild cognitive impairment (MCI) after age 65 are more likely to have biological and brain imaging markers that reflect a greater vulnerability for accelerated brain aging, according to a study conducted by researchers at the University of Pittsburgh School of Medicine. The findings were published online in Molecular Psychiatry.

Older adults with have double the risk of developing dementia in the future compared with those who have never had the , said senior investigator Meryl A. Butters, Ph.D., associate professor of psychiatry, Pitt School of Medicine. But there's no clear explanation for why a treatable mood disorder like depression leads to increased risk for dementia, a progressive disease. Until now, most studies have examined only one or two biomarkers to get at this question.

"Our study represents a significant advance because it provides a more comprehensive and integrated view of the neurobiological changes related to in late-life," she said. "Better understanding of the neurobiology of cognitive impairment in depression can provide new targets for developing more specific treatments, not only for its prevention and treatment, but also for its down-stream negative outcomes, including the development of dementia and related disorders."

The team collected blood samples from 80 in remission after being treated for major depression, 36 of whom had MCI and 44 with normal cognitive function. Their blood was tested for 242 proteins involved in biologic pathways associated with cancer, cardiovascular diseases, and metabolic disorders as well as psychiatric and neurodegenerative disorders. The researchers also performed PET and MRI brain scans on the participants to look for indicators of cerebrovascular disease, brain atrophy or shrinkage, and beta-amyloid, which is the protein that makes up the brain plaques associated with Alzheimer's disease.

The MCI group was more likely to have differences in the biologic activity of 24 proteins that are involved in the regulation of immune and inflammatory pathways, intracellular signaling, cell survival, and protein and lipid balance.

Brain scans revealed a greater propensity for – for example, small strokes – in the MCI group, but there was no difference in the amount of beta-amyloid deposition.

"If you take these results altogether, they suggest that people with depression and cognitive impairment may be more vulnerable to accelerated brain aging, which in turn puts them at risk for developing dementia," Dr. Butters said. "Ultimately, if we can understand what happens in the brain when people are depressed and suffer , we can then develop strategies to slow or perhaps stop the impairment from progressing to dementia."

Next steps include assessing the protein panel in older people with normal cognitive function who have not experienced .

Explore further: Late-life depression associated with prevalent mild cognitive impairment, increased risk of dementia

Related Stories

About one-quarter of patients with MCI progress to dementia

March 12, 2014

(HealthDay)—About 22 percent of patients with mild cognitive impairment (MCI) progress to dementia within three years, and depression symptoms modify the prognosis, according to a study published in the March/April issue ...

Depression in the elderly linked to Alzheimer's risk

June 9, 2014

Many people develop depression in the latest stages of life, but until now doctors had no idea that it could point to a build up of a naturally occurring protein in the brain called beta-amyloid, a hallmark of Alzheimer's ...

How is depression related to dementia?

July 30, 2014

A new study by neuropsychiatric researchers at Rush University Medical Center gives insight into the relationship between depression and dementia. The study is published in the July 30, 2014, online issue of Neurology, the ...

Recommended for you

Umbilical cells help eye's neurons connect

November 24, 2015

Cells isolated from human umbilical cord tissue have been shown to produce molecules that help retinal neurons from the eyes of rats grow, connect and survive, according to Duke University researchers working with Janssen ...

Brain connections predict how well you can pay attention

November 24, 2015

During a 1959 television appearance, Jack Kerouac was asked how long it took him to write his novel On The Road. His response – three weeks – amazed the interviewer and ignited an enduring myth that the book was composed ...

No cable spaghetti in the brain

November 24, 2015

Our brain is a mysterious machine. Billions of nerve cells are connected such that they store information as efficiently as books are stored in a well-organized library. To this date, many details remain unclear, for instance ...

Neurons encoding hand shapes identified in human brain

November 23, 2015

Neural prosthetic devices, which include small electrode arrays implanted in the brain, can allow paralyzed patients to control the movement of a robotic limb, whether that limb is attached to the individual or not. In May ...

Wireless sensor enables study of traumatic brain injury

November 23, 2015

A new system that uses a wireless implant has been shown to record for the first time how brain tissue deforms when subjected to the kind of shock that causes blast-induced trauma commonly seen in combat veterans.


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.