Young adults who seem to be healthy, but have a clustering of heart disease risks factors known as metabolic syndrome, tend to have signs of thickening of their carotid artery walls, which is an early indication of atherosclerosis, according to a new study in the Aug 2, 2005, issue of the Journal of the American College of Cardiology.
“What was surprising is how the constellation of abnormalities in patients with metabolic syndrome worked together to create a significant degree of subclinical atherosclerosis in individuals so young. They were only 32 years old on average, but if they had the metabolic syndrome, they were more likely to have thickening of the carotid walls expected in subjects who were much older - indicating that their arteries were “aging” more quickly. This provides a powerful message that maintaining healthy habits should be a lifelong venture. It also shows that risk factor assessment and modification, if needed, should begin much earlier than in middle age,” said James H. Stein, M.D., F.A.C.C., at the University of Wisconsin Medical School in Madison.
The researchers, including lead author Wendy S. Tzou, M.D., studied 507 young adults (20 to 38 years old) who were participants in the Bogalusa Heart Study, which is a long-running heart health study following healthy white and African-American children and adults in Bogalusa, Ala.
Using ultrasound, the researchers measured the thickness of the inner layers of the carotid arteries. Carotid intima-media thickness can identify subclinical atherosclerosis, that is, hardening and thickening of the arteries before an individual feels any symptoms. The artery wall thickness is a predictor of cardiovascular risk.
The study participants were also classified as having metabolic syndrome if they met a set of criteria that included combinations of large waists or high body-mass index, elevated triglycerides, low HDL (“good”) cholesterol, elevated blood pressure and elevated blood sugar or insulin levels.
“Metabolic syndrome has been shown to be associated with atherosclerosis and increased cardiovascular risk among middle-aged and older adults. However, this is the first study to demonstrate that metabolic syndrome is associated with increased subclinical atherosclerosis in otherwise healthy young adults,” Dr. Stein said. “Those with the thickest carotid artery walls were two to three times more likely to have metabolic syndrome, independently of age, sex, race and smoking status.”
The authors wrote that the results support screening and early intervention among young people with metabolic syndrome, even if they feel healthy.