Early Adulthood Depression Associated With Dementia Later in Life

Depression in early adulthood can lead to issues with cognition later in life, according to a study published in the Journal of Alzheimer’s Disease. The research suggests that depression can lead to lower cognition in 10 years and to cognitive decline in old age.

“Several mechanisms explain how depression might increase dementia risk,” said Willa Brenowitz, PhD, MPH, in a press release. “Among them is that hyperactivity of the central stress response system increases production of the stress hormones glucocorticoids, leading to damage of the hippocampus, the part of the brain essential for forming, organizing and storing new memories.”

The investigators predicted the average trajectories of depressive symptoms for approximately 15,000 participants between 20 and 89 years of age, divided into the categories “older,” “midlife,” and “young adulthood.” Then, the researchers applied these predicted trajectories and found that the odds of cognitive impairment were 73% higher for patients estimated to have elevated depressive symptoms in early adulthood and 43% higher for those estimated to have these symptoms in later life among approximately 6000 older participants.

Participants were screened for depression using the CESD-10, a 10-question assessment evaluating symptoms throughout the past week. Moderate or high depressive symptoms were found in 13% of young adults, 26% of midlife adults and 34% of older participants. To estimate depressive symptoms across each life stage, the investigators pooled data from younger participants with data from the approximately 6000 older participants and predicted average trajectories.

According to the study, 1277 participants were diagnosed with cognitive impairment following neuropsychological testing, evidence of global decline, documented use of a dementia medication, or hospitalization with dementia as a primary or secondary diagnosis.

“Generally, we found that the greater the depressive symptoms, the lower the cognition and the faster the rates of decline,” Brenowitz said in the release. “Older adults estimated to have moderate or high depressive symptoms in early adulthood were found to experience a drop in cognition over 10 years.”

REFERENCE

Happiness in early adulthood may protect against dementia [news release]. Science Daily; September 28, 2021. Accessed October 28, 2021. https://www.sciencedaily.com/releases/2021/09/210928121341.htm