WEDNESDAY, Oct. 6, 2021 (HealthDay News) — Happy young adults may be somewhat protected from dementia, but the opposite may also be true: If you’re a depressed young person, your odds of developing dementia go up, a new study suggests.
“Overall, we found that the higher the symptoms of depression, the lower the cognition and the faster the rates of decline,” said researcher Willa Brenowitz.
“Older adults are thought to have moderate or high depressive symptoms early in adulthood, and they have been shown to have cognitive decline over a 10-year period,” added Brenowitz, of the University of California, Department of Psychiatry and Behavioral Sciences in San Francisco.
The researchers developed a statistical model to predict the average arc of depression among 15,000 participants between the ages of 20 and 89. They found that in a group of about 6,000 older adults, the odds of cognitive impairment were 73% higher for those who developed depressive symptoms in early adulthood, and 43% higher for those who developed depressive symptoms later in life.
“Several mechanisms explain how depression may increase the risk of developing dementia,” Brenowitz said in a university news release. “Among them is that hyperactivity in the central stress response system increases production of glycolytic stress hormones, resulting in damage to the hippocampus, a part of the brain essential for the formation, organization and storage of new memories.”
Other studies have linked depression to hippocampal shrinkage, and one study showed faster rates of volume loss in women, she says.
In this study, participants were screened for depression. Moderate or high depressive symptoms were found in 13% of young adults, 26% of middle-aged adults, and 34% of older participants. More than 1,200 participants were diagnosed with cognitive impairment.
With up to 20% of the population experiencing depression during their lifetime, it is important to recognize its role in cognitive or mental aging, said researcher Dr. Kristen Yaffe, of the Department of Psychiatry and Behavioral Sciences at the University of California, San Francisco.
“Future work will be needed to confirm these findings, but in the meantime, we must screen and treat depression for many causes,” Yaffe said in the statement.
The report was published on September 28 in Alzheimer’s Disease Journal.
The Alzheimer’s Association has more on dementia.
Source: University of California, San Francisco, press release, September 28, 2021