Hardened Arteries Threaten Obese, Diabetic Youth
TUESDAY May 26, 2009 -- An examination of the neck arteries of today's obese or diabetic young people bodes ill for their future health, researchers report.
The walls of these carotid arteries, which carry blood to the brain, showed a thickening and stiffness known to increase the risk of future strokes, heart attacks and other cardiovascular problems, according to a report to be published in the June 9 issue of Circulation.
"Since the 1980s, there has been a major increase in obesity in our youth," said Dr. Elaine Urbina, director of preventive cardiology at Cincinnati Children's Hospital Medical Center, associate professor of pediatrics at the University of Cincinnati and lead author of the report. "This could be the first generation of Americans that has a shorter life expectancy than its parents," she said.
In the study, Urbina and her team used ultrasound to assess the carotid arteries of a few hundred young people (average age 18) -- 182 who were lean, 128 diagnosed with type 2 diabetes (often tied to obesity), and 136 classified as obese because their weight-for-height was above the 95th percentile. "It was one of the larger studies of carotid thickness in adolescents," Urbina said.
The researchers looked at the thickness of the intima, one of the layers of tissue that line the arteries.
"If you have diabetes, the intima is thicker than if you don't have diabetes," Urbina said. "If you are obese, the artery is also thicker. Stiff carotids are linked to heart attacks as well as strokes, because if you are having a buildup of plaque in the arteries that lead to the brain, you probably are having a buildup in the coronary arteries as well."
Plaque is the term for the fatty deposits that can increase in size and thickness until they limit or totally block normal blood flow.
The young people who were obese or had diabetes were more likely to have other risk factors for cardiovascular disease, such as higher blood pressure and high levels of blood fats such as cholesterol, the study found. But those factors did not account for the significant changes in artery structure and function, the researchers said.
According to Urbina, the detection of unhealthy artery changes in young, obese or diabetic people "demonstrates the need for research in this area."
One expert said the findings reinforce prior research.
"This is more evidence that obesity is not good for young people," said Dr. Robert H. Eckel, professor of physiology and biophysics at the University of Colorado, a spokesman for the American Heart Association. However, it's not clear from the study how damaging obesity might be in these young people, Eckel said.
"How important [the findings are] in terms of what is to follow is not clear," he said, noting that the consequences for adult health of obesity in childhood are not set in stone.
"There can be intervention to modify risk, not necessarily to reduce obesity but to control blood pressure and blood lipids more aggressively. I would like to see further studies that follow these young people with and without intervention for 10 years," Eckel said.
In the meantime, rising childhood obesity is now a troubling fact of life for doctors who see young patients, Urbina added. A kilogram equals 2.2 pounds, and "at least once a month, I see a child who weighs more in kilograms than I weigh in pounds," she said. "Yesterday, I saw that in an 11-year-old."
The child and youth obesity problem is an issue for schools as well as parents, Urbina said. Schools must play a role, because "80 percent of the calories children consume are outside the control of parents," she said, and also because schools often do not emphasize physical activities that can help prevent excess weight gain.
"We need better nutrition and better after-school programs," she said.
There's more on obesity in the United States at the U.S. Centers for Disease Control and Prevention.
Posted: May 2009