Older adults who show signs of apathy tend to have a smaller
brain volume than their peers with more vim and vigor, a new
study suggests. Researchers found that of more than 4,300
older adults, those with at least two symptoms of apathy had
slightly less gray matter and white matter in their brains.
Gray matter basically acts as the brain's
information-processing centers, while white matter is like
the wiring connecting those centers. While the study tied
apathy to reduced brain volume, it didn't prove a
cause-and-effect relationship. It's possible that apathy
could serve as a "warning sign" of increased dementia risk
or some other disorder affecting the brain, according to
study co-author. But she said more research is needed to
understand what is going on. The findings are based on 4,354
adults from Iceland, mainly in their 70s, who underwent MRI
scans to measure their brain volume. They also answered
three questions aimed at gauging apathy: "Have you dropped
many of your activities and interests?" "Do you prefer to
stay at home, rather than going out and doing new things?"
and "Do you feel full of energy?" Almost half of the study
participants had two or three signs of apathy. And on
average, research team found, they had slightly smaller brain volume than those
with one or no signs of apathy. That leaves open the
chicken-and-egg question. "We can't say which comes first,
apathy or changes in the brain consistent with symptoms of
apathy," she said. The researchers did try to tease out
whether certain health conditions could explain the
connection. Apathy symptoms are common in people with
depression, for example, but research
team found that apathy was tied to lower brain volume
even in the absence of depression. People with Alzheimer's
or other forms of dementia often become apathetic as well,
but none of the study participants had dementia. The
researchers also factored in diabetes, high blood pressure,
smoking and study participants' exercise levels and walking
speeds. Apathy was still linked to lower brain volume.
Another possibility, according to research team, is that
"cerebral small-vessel disease" plays some role. That refers
to damage to the small blood vessels of the brain, from
conditions like high blood pressure and diabetes.
Small-vessel disease can lead to what doctors call vascular
dementia -- which is second to Alzheimer's as the most
common form of dementia. For now, study co-author suggested
that older adults who notice a loss of energy or motivation
bring it up to their doctor. She said it could be a sign of
some underlying problem that warrants a closer look.
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