experienced during early adulthood increases the risk of developing
cognitive impairment and dementia later in life, a new study reports.
research has shown that poor cardiovascular health can damage blood
flow to the brain increasing the risk for dementia, a new study led by
UC San Francisco indicates that poor mental health may also take its
toll on cognition.
research adds to a body of evidence that links depression with
dementia, but while most studies have pointed to its association in
later life, the UCSF study shows that depression in early adulthood may
lead to lower cognition 10 years later and to cognitive decline in old
The study publishes in the Journal of Alzheimer’s Disease on Sept. 28, 2021.
researchers used innovative statistical methods to predict average
trajectories of depressive symptoms for approximately 15,000
participants ages 20 to 89, divided into three life stages: older,
midlife and young adulthood.
then applied these predicted trajectories and found that in a group of
approximately 6,000 older participants, the odds of cognitive impairment
were 73 percent higher for those estimated to have elevated depressive
symptoms in early adulthood, and 43 percent higher for those estimated
to have elevated depressive symptoms in later life.
results were adjusted for depressive symptoms in other life stages and
for differences in age, sex, race, educational attainment, body mass
index, history of diabetes and smoking status. For depressive symptoms
in midlife, the researchers found an association with cognitive
impairment, but this was discounted when they adjusted for depression in
other life stages.
Excess Stress Hormones May Damage Ability to Make New Memories
mechanisms explain how depression might increase dementia risk,” said
first author Willa Brenowitz, PhD, MPH, of the UCSF Department of
Psychiatry and Behavioral Sciences and the Weill Institute for
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.”
studies have linked depression with atrophy of the hippocampus, and one
study has shown faster rates of volume loss in women, she said.