Depression, especially its physical signs, such as
fatigue and loss of appetite, may contribute to thickening
arteries, an early sign of cardiovascular disease, researchers
report.
Previous research has suggested
that negative emotions like anxiety and anger can increase
the risk for heart disease. But in the new study, depression
-- and its physical symptoms -- was the emotional linchpin
to early signs of heart disease.
"In other studies, anxiety, depression, anger and hostility
have all separately been linked to future risk of heart
disease," said lead researcher Jesse C. Stewart, a member
of the psychology department at Indiana University-Purdue
University Indianapolis. But the problem with those studies
was that they didn't look at these negative emotions together.
And since their symptoms can overlap, it has been hard
to tell which emotion plays the most important role in
heart disease, he said.
For the study, Stewart's team looked for emotional links
to heart disease among 324 men and women with an average
age of 60.6 years old. To determine early signs of heart
disease, the scientists examined carotid artery intima-media
thickness, which is a measure of the inner layers of the
arteries and is related to early stage heart disease.
Measurements were taken at the start of the study and
again three years later.
"We found that mild to moderate depressive symptoms were
associated with greater progression of subclinical atherosclerosis
[hardening of the arteries] -- greater increase of the
artery wall," Stewart said. "In contrast, anxiety symptoms,
hostility and anger were not at all related to a change
in the blood vessel thickness."
What's more, analysis showed that only the physical symptoms
of depression predicted the progression of atherosclerosis.
And it appears that the symptoms of depression exist before
the signs of atherosclerosis, Stewart said.
The findings are published in the February issue of the
Archives of General Psychiatry.
Stewart isn't sure why depression has this effect. "Depression
has been associated with some physiological changes, including
in the immune system. These physiological changes probably
explain this association," he said.
The study also found that the 5 percent of study participants
taking antidepressants fared better than those with depression
who weren't taking the drugs. "They had significantly
reduced progression of atherosclerosis," Stewart said.
But, because the sample was so small, it isn't possible
to make a definitive statement about the value of selective
serotonin reuptake inhibitors (SSRIs) in reducing atherosclerosis,
Stewart said. "There is intriguing evidence that SSRIs
may be associated with reduced progression of atherosclerosis,"
he said.
Stewart thinks the study findings may help in treating
and preventing heart disease.
"Identifying the harmful aspects of emotion could lead
to the identification of people who are at risk for heart
disease due to their tendency to experience negative emotions
and who may benefit from psychological and pharmacological
intervention," he said. "Identifying these harmful aspects
could also lead to the development of more focused and
potent interventions."
Dr. Nieca Goldberg, chief of women's cardiac care at
Lenox Hill Hospital in New York City, noted that depressed
people are less likely to take care of themselves and
have more risk factors for heart disease.
"People who are depressed don't adopt a healthy lifestyle,"
said Goldberg, a spokeswoman for the American
Heart Association and author of The Women's
Healthy Heart Program. "They overeat, smoke more,
may drink more. In addition, people who have depression
have platelets that are more likely to clot."
Goldberg thinks doctors should pay closer attention to
depression and other psychological factors that can affect
patient health.
"For too long, the medical system has amputated the head
from the rest of the body," she said. "It is important
for us to consider the psychological aspects of our patients'
lives, because that is an important factor in our care
of a patient."
