THURSDAY, March 31, 2005 (HealthDay News) -- Inflammation may be the reason why that "spare tire" around the waist raises a person's risk of heart disease, researchers report.
"It is well known that obesity affects nearly one-third of adults in the United States and is closely linked with heart disease," study lead author Tongjian You, a geriatric medicine instructor at Wake Forest University Baptist Medical Center, said in a prepared statement. "While we don't fully understand the link between obesity and heart disease, our study suggests that inflammatory proteins produced by fat itself may play a role."
Reporting in the April issue of the American Journal of Physiology, You's team examined 20 post-menopausal women, ages 50 to 70, who were overweight or obese, with waistlines measuring over 35 inches.
They checked each woman's abdominal fat for two proteins that promote inflammation -- interleukin 6 and tumor necrosis factor alpha -- and for a third protein that encourages blood clots, called plasminogen activator inhibitor 1.
These three proteins are all manufactured by fat tissue and play a role in narrowing of the arteries, the researchers say.
They also checked for two "good" proteins: leptin, which regulates energy metabolism; and adiponectin, which has anti-inflammatory properties.
Eight of the women were diagnosed with what's known as metabolic syndrome, a common cluster of symptoms (such as obesity, high blood cholesterol and high blood pressure) that all increase an individual's risk for heart disease. According to the researchers, the women with metabolic syndrome had adiponectin levels that were 32 percent lower than the 12 women who didn't have the disorder.
"This suggests that low production of adiponectin in subcutaneous fat is linked with an elevated risk of heart disease," You said.
"It's possible that modifying the inflammatory proteins through medication could also lower the risk of heart disease," added senior researcher Barbara Nicklas, an associate professor of internal medicine. "The findings point to a possible treatment target for new drugs. Our goal is to learn more about how these proteins are produced and how levels can be changed."
The researchers are currently conducting a study to determine whether diet and exercise affect the levels of these proteins.
The American Medical Association has more about preventing heart disease.