MONDAY, May 2, 2005 (HealthDay News) -- Weight gain plus an increase in blood levels of "bad" low-density lipoprotein (LDL) cholesterol work together to raise risks for atherosclerosis in postmenopausal women, new research shows.
The study involved 21 postmenopausal women (average age 55) and 10 premenopausal women (average age 23). All the women were healthy, but sedentary. Researchers found the carotid arteries -- those supplying blood to the brain -- of the postmenopausal women were 56 percent less elastic than in the younger women, raising risks for cardiovascular events such as stroke.
The researchers found that oxidative stress on cells, which is higher after estrogen production drops sharply after menopause, may play a role in artery stiffening.
Oxidative stress occurs when molecules called oxygen-free radicals attack cells, including cells that line arteries. Oxidative stress can also occur as a result of low levels of healthy antioxidants in the body.
After menopause, many women experience a shift in body fat that results in more fat accumulating in the abdomen, study co-author Kerrie L. Moreau, an assistant research professor at the University of Colorado at Boulder, said in a prepared statement. This increase in abdominal fat can cause the body's sympathetic nervous system to become more active and result in a reduction in arterial responsiveness.
These factors, combined with increased LDL cholesterol levels after menopause, can contribute to the development of oxidative stress.
"Taken together, all these factors -- increased abdominal fat, elevated sympathetic nervous system activity, higher LDL cholesterol, and loss of estrogen, produce oxidative stress which, in turn, contributes to a loss of elasticity in arteries," Moreau said.
According to the researchers, the good news is that most of these risk factors can be prevented or minimized by regular exercise, coupled with a healthy diet.
The American College of Physicians has more about heart disease.