Children with risk factors such as high blood pressure, obesity, diabetes and high cholesterol levels already show signs of fatty build-up in their arteries that could lead to heart attack in adulthood, researchers reported at the American Heart Association’s Scientific Sessions 2006.
“Primary prevention of heart disease must start in childhood,” said Sanaz Piran, M.D., internal medicine resident at McMaster University in Hamilton, Ontario, Canada. “We need to start looking at and treating risk factors for heart disease in children.”
Researchers reviewed 26 studies from the United States, the Netherlands, Australia, Finland, Norway and Italy that used non-invasive methods to measure the thickness of the artery walls and blood flow in arteries of children without risk factors, as well as in children with risk factors for cardiovascular disease.
Researchers used ultrasound in three of the studies to examine stiffness in the artery wall. They measured carotid artery intima-media thickness (CIMT), an ultrasound measurement of the thickness of the neck arteries, to determine the level of atherosclerosis. They found that children with risk factors for heart disease and stroke had an average of 8.7 percent more thickening than children without risk factors. Atherosclerosis is the fatty build-up of plaque in the inner walls of the arteries. It can lead to heart attack or stroke.
Another noninvasive test – brachial or femoral artery flow-mediated dilation (FMD) – showed an average 37 percent decreased blood flow in children with risk factors compared to those without. FMD measures endothelial dysfunction, which occurs when blood vessels aren’t flexible enough to expand in response to increased blood flow. In FMD, the flow of blood either in the arm or thigh is gauged with ultrasound after a cuff is inflated and deflated. FMD is a validated measure of early atherosclerosis.
“These results indicate structural abnormalities and artery wall dysfunction, both signs of the early stages of atherosclerosis,” Piran said. “Children with risk factors are showing the markers for sub-clinical atherosclerosis.”
The 26 studies included 3,630 children, age 5 to 18, and compared healthy children to children with cardiovascular risk factors such as high blood pressure, high cholesterol levels, diabetes and obesity.
In 15 studies, researchers measured the children’s CIMT and in eight studies either arm or thigh artery FMD. Thickening of the carotid artery wall is an early sign of atherosclerotic disease that could indicate a higher risk of stroke or disease elsewhere in the body’s arteries, which means a higher risk of heart disease.
Twelve of 15 studies with CIMT showed that the artery wall thickness was higher in children with risk factors. All eight studies testing FMD showed that subgroups of children with risk factors had reduced dilation (expansion) of the artery. Three other ultrasound studies showed that children with risk factors were more likely to have arterial stiffness in neck arteries.
The research highlights the need for parents and physicians to target cardiovascular risk factors in children, Piran said.
“Diet and exercise are especially important to curb the escalating problem of childhood obesity,” she said. “Obesity puts children at risk for high blood pressure, diabetes and high cholesterol levels. Children’s diets have changed dramatically, influenced by television commercials and the convenience of fast foods. Children are eating too much fatty and processed foods. Parents need to involve their kids in regular exercise activities and cut down on fatty meals, emphasizing healthy foods such as vegetables.”
Piran also suggested that parents who smoke should not smoke in the presence of their children. And if there is a family history of elevated cholesterol, then children in the family should have their cholesterol levels checked.
“The very things we recommend to adults should be recommended to parents for their children,” she said. “There needs to be a family-oriented approach to cardiovascular prevention and to addressing these risk factors.”
Co-authors are Katherine Morrison, M.D., and Eva Lonn, M.D.
This study was funded by the Population Health Research Institute (PHRI) at McMaster University in Hamilton, Ontario, Canada.