ATLANTA, November 10, 1999 — Extra fat around the waist sets off a chain of events leading to life-threatening arterial stiffness, according to researchers from the University of Pittsburgh’s Graduate School of Public Health in a presentation delivered Wednesday, Nov. 10, at the 72nd Scientific Sessions of the American Heart Association in Atlanta.
"This study is the first to show that as they age, people with excess abdominal fat--particularly men--have correspondingly high degrees of arterial stiffness," said Kim Sutton-Tyrrell, D.Ph., associate professor of epidemiology at the University of Pittsburgh and principal investigator of the study.
"Of all the risk variables we evaluated, abdominal fat was second only to blood pressure in predicting stiffness of the major blood vessel, the aorta. The extent of abdominal fat appears to be a highly effective predictor of stiffness of the arteries," said Dr. Sutton-Tyrrell. "The amount of abdominal fat may help medical practitioners predict arterial stiffness and cardiovascular disease risk."
Arterial stiffness increases with age and with increases in systolic blood pressure and can be viewed as a measure of the aging of the vascular system. The condition is associated with risks of cardiovascular disease and stroke. Increased waist circumference is also associated with the risk of diabetes mellitus.
"This study sounds a warning bell to avoid weight gain. And if you’re already overweight, here is one more important reason to exercise and reduce," concluded Dr. Sutton-Tyrrell.
Abdominal, or visceral fat, which accumulates around the abdominal organs and adds to girth, represents a greater risk to vascular health than does subcutaneous fat, which is found in other areas of the body and lies just under the skin.
"The risk factors are tied to one another," explained Dr. Sutton-Tyrrell, "but exercising and losing weight will turn the tide and help to stabilize risk factors, resulting in better vascular health."
The study involved 2,134 adults aged 70-79 who were enrolled in Health ABC, a longitudinal study of aging and changes in health, body composition and function. Researchers used CT scans to measure abdominal fat. Also evaluated were the speed of blood within the aorta, history of smoking, fasting insulin and glucose, levels of hemoglobin A1C (an indirect measure of blood glucose), heart rate, weight, abdominal circumference, thigh fat area, abdominal fat and high-density lipoprotein cholesterol.
African-Americans and those with risk factors such as smoking, hypertension, older age, higher heart rate and higher hemoglobin A1C levels also were found to be at increased risk of vascular stiffness.