MONDAY, Nov. 10, 2003 (HealthDayNews) -- An estimated one in eight U.S. schoolchildren has risk factors that could signal heart disease in the years to come.
That's the sobering conclusion of a study presented Nov. 9 at the American Heart Association's annual conference in Orlando, Fla.
Researchers from the University of North Carolina at Chapel Hill found approximately 13 percent of the schoolchildren studied have at least three of the risk factors for what doctors call metabolic syndrome, a precursor of cardiovascular disease.
Girls had a 1.6 times higher risk than boys, says Joanne S. Harrell, director of the university's Center for Research on Chronic Illness, who presented the findings.
Metabolic syndrome includes such risk factors as high blood pressure, elevated triglycerides (a fatty substance found in the blood), obesity, and low levels of the so-called "good" HDL cholesterol. Those who have metabolic syndrome are at early risk of heart disease as well as diabetes.
"This study shows a much higher prevalence of metabolic syndrome in children than other studies have shown," Harrell says, adding that's partly because so many children in the study were overweight.
If nothing is done, she says, there's a good chance the children could develop both heart disease and type 2 diabetes.
Harrell's team followed more than 3,200 students, evenly split between boys and girls 8 to 17 years old, in a rural North Carolina county with no cities of more than 50,000 people. The researchers decided to study students in rural areas with high minority populations because they knew that those children have slightly higher obesity rates and that type 2 diabetes is more common in minorities.
They evaluated each student's body mass index (BMI) -- a ratio of weight to height -- to determine if it was high enough to be labeled obese, as well as other risk factors such as blood pressure, blood fats and how well their body utilized glucose. A BMI of 30 and above is considered obese; 25 and higher is overweight.
More than half of the children had a least one of the six risk factors for metabolic syndrome, 27.4 percent had two or more, and 13.5 percent had at least three risk factors. Some children who had three or more factors were only 8 or 9 years old.
The most common risk factor, found in more than 43 percent of the children, was a low HDL cholesterol level. More than one in four of the students were classified as overweight.
In all, 16.3 percent of the girls and 10.7 percent of the boys had at least three risk factors for metabolic syndrome. That was due, Harrell says, to the higher levels of excess weight in the girls.
"There's no surprise in this study. The evidence [of heart-disease risk factors in children] just keeps piling up," says Dr. Henry C. McGill, a senior scientist emeritus at the Southwest Biomedical Research Institute in San Antonio.
McGill recently wrote an editorial in the Journal of the American Medical Association, commenting on two other new studies linking risk factors found in children that help predict heart problems later. One, the so-called Bogalusa Heart Study, followed Louisiana children into young adulthood and found that high levels of so-called "bad" LDL cholesterol was the best predictor later in life of a condition called increased carotid artery thickness.
In the second study, Finnish researchers followed more than 2,000 children and teens and measured blood pressure, cholesterol, weight levels and smoking habits. They found if the children had several risk factors earlier in life, they were at increased risk of hardening of the arteries that can lead to heart problems later.
McGill says the studies should definitely be a wake-up call for parents and pediatricians. "My message is, we have got to start early to stop heart disease in middle age."
"Start with smoking," he urges. "Get them to quit."
Then, work on the weight. "The epidemic of obesity at all ages -- especially in children -- is a time bomb that will soon explode to cause a renewal of the epidemic of coronary heart disease and wipe out the gains of the last 30 years, during which time the mortality rate of CHD [coronary heart disease] has decreased by more than 50 percent," he says.
Harrell suggests that parents should help their kids improve their eating habits and keep them active, for instance, work as a family to get regular exercise.
Also, she adds, "Advocate to your school for more vigorous and more frequent regular activity. It's easier to work on activity first."