We hear plenty about the dangers
of high cholesterol levels, but low levels apparently
confer their own risks. Naturally low cholesterol levels
are associated with poorer performance on a variety
of cognitive measures, according to a new study.
"It is not entirely surprising
that lower cholesterol levels were associated with moderately
lower levels of cognitive function, given (that) cholesterol
is important in brain function," Dr. Penelope K. Elias
from Boston University stated.
Previous reports have
related both high and low total cholesterol levels to
deficits in cognitive performance, Elias and her colleagues
explain in the journal Psychosomatic Medicine.
The team used data from
789 men and 1105 women participating in the original
cohort of the Framingham Heart Study to examine the
relationship between total cholesterol and cognitive
Individuals in the lowest
total cholesterol group (less than 200 units) performed
more poorly than patients with higher cholesterol levels
on tests of similarities, word fluency, attention/concentration,
and overall, the investigators report.
Participants in the lowest
total cholesterol group were 49 percent more likely
than were participants in the highest total cholesterol
group (240-380) to perform poorly, and 80 percent more
likely to perform very poorly, the results indicate.
Do the findings raise
questions about treating high cholesterol? "It is important
to note that we did not examine the association between
cognition (and) cholesterol-lowering via medications,"
"In fact, a unique aspect
of the study was that few of our participants were being
treated with anti-cholesterol drugs; in other words,
we looked at 'naturally low and high levels of cholesterol',"
she pointed out.
"Naturally low levels
of cholesterol and lowered levels of cholesterol may
have very different ramifications for cognitive function,"
Elias said. "Thus, our study does not have implications
for the guidelines for treatment of high cholesterol."
Medicine, January/February 2005.