For some people, the body's reaction to
stress may raise the odds of developing high cholesterol,
the results of a new study suggest.
Researchers in the UK found that healthy middle-age adults
whose cholesterol rose in response to a stressful task
were more likely than their peers without this increase
to have high cholesterol several years later.
It's been known that blood cholesterol can show a short-lived
rise in response to stress, study co-author Dr. Andrew
Steptoe stated. The new findings, he said, suggest that
these transient increases may predict long-term elevations
in cholesterol.
A number of studies have linked chronic stress to a higher
risk of heart disease, and it's possible that stress-related
changes in cholesterol contribute to this, according to
Steptoe, who is based at University College London.
Steptoe and colleague Lena Brydon report the findings
in the journal Health Psychology.
To see if stress-related spikes in cholesterol can have
long-range effects, the researchers followed 199 middle-aged
adults over 3 years. At the start of the study, participants
performed two moderately stressful computer-based tasks;
blood samples were taken before and after the tests to
measure any changes in cholesterol levels. The men and
women were then divided into three groups based on the
extent of their cholesterol response.
Three years later, participants had their blood cholesterol
measured again. Those in the group with the greatest cholesterol
response to stress were the most likely to have high cholesterol.
Overall, 56 percent had a total cholesterol level that
surpassed the cutoff for diagnosing high cholesterol,
compared with only 16 percent of the group whose cholesterol
levels had been least affected by stress.
Even when the researchers weighed other factors such
as age, body weight and smoking, the group with the highest
stress response was 13 times more likely than the group
with the lowest response to have high cholesterol 3 years
later.
They were also four times more likely to have high levels
of LDL cholesterol, the "bad" form that contributes to
artery-clogging plaques.
The findings suggest that chronic stress can contribute
to high cholesterol in some people, though the reason
is unclear, according to Steptoe and Brydon.
One possibility, they note, is that changes in metabolism
in response to stress ultimately cause the liver to boost
production of LDL particles. There is also evidence that
stress can temporarily limit the body's clearance of cholesterol
from the blood.
According to Steptoe, it's possible that such effects
could be modified if people changed their conscious reactions
to stress.
Stress management, he noted, has been shown to lower
levels of the stress hormones cortisol and epinephrine.
Steptoe said he is not aware of any studies that have
tested whether the same is true of cholesterol levels.
SOURCE: Health Psychology, November 2005.
- More articles on Stress
