The arteries of obese children may be aging 30 years faster than normal, new research suggests.

A study of 70 boys and girls found obese children and teens with abnormal cholesterol had thicker carotid arteries, the arteries in the neck that supply blood to the brain.

Thickened neck arteries are a sign of fatty buildup of plaque within the arteries feeding the heart muscle and brain.

The neck arteries in the obese children, aged 13 on average, “are looking like those of a 45-year-old,” says Dr. Geetha Raghuveer, associate professor of pediatrics at the University of Missouri Kansas City School of Medicine, and cardiologist at Children’s Mercy Hospital.

Given the scope of the obesity crisis, the findings suggest a generation of children is at risk for premature cardiovascular disease.

“Kids almost never have heart attacks, no matter how high their risk may be,” Raghuveer says. What’s more, “I’m hoping they don’t have hard calcified plaque like older adults. I’m very hopeful we may be able to reverse this process.”

“But it is very possible that these kids - especially the cohort of obese kids we’ve been seeing in the last decade or so - may grow up to be young adults who may well have premature angina or heart attack, even as early as their 30s.”

The children’s “vascular age” surprised doctors in Canada.

“I thought they would be at increased risk, but I didn’t think that it would be that bad,” says Dr. Brian McCrindle, professor of pediatrics and staff cardiologist at Toronto’s Hospital for Sick Children.

“We know that kids with cardiovascular risk factors and obesity have thicker lining to their carotid arteries than kids without those conditions,” McCrindle says.

“What this study does is, it actually gives it an age.”

Autopsy studies showed decades ago that fatty streaks and narrowing of the arteries can develop in the late teens and early 20s, says Dr. Geoff Ball, assistant professor in the department of pediatrics at the University of Alberta in Edmonton.

But the new study used ultrasound to detect subtle changes in the main arteries, he says. “These small changes are early steps in the genesis” of cardiovascular disease.

The study was small, and it’s not clear if the ultrasounds are picking up early, or advanced lesions.

But, “it’s one more piece of evidence that if we don’t start taking this childhood obesity epidemic seriously, we’re going to wind up with health problems that could potentially swamp the whole health-care system,” McCrindle says.

In Canada, 18 per cent of children aged two to 17 are overweight, and another eight per cent - an estimated 500,000 children - are obese.

The new study, to be presented Wednesday at the American Heart Association’s scientific sessions in New Orleans, involved 34 boys and 36 girls seen at a cardiology clinic.

All had risk factors such as obesity, abnormal levels of different types of cholesterol or a family history of premature cardiac death.

The children’s vascular age - the age at which their level of thickening would be normal - was calculated by comparing their carotid artery thickness to that of 45-year-old matched for race and gender. The researchers used a 45-year-old, because there is no data to compare them to normal, healthy children.

Overall, about 75 per cent of the children in the study plotted “advanced vascular age”, Raghuveer says. The effect was strongest in children with a high body mass index and high triglyceride levels.

“Their arteries and their hearts are probably behaving like that of middle-aged adults,” Raghuveer says. What’s not clear is whether “they just advance, advance, advance, or do they plateau out?”

Her group hopes to look at whether diet, exercise or medication can have an impact on the children’s artery wall thickness.

In the U.S, some groups have recommended that cholesterol-lowering drugs be prescribed more frequently to children at high risk. But Ball, of the University of Alberta, says the approach of most Canadian pediatricians “is generally more conservative.”