News - Hypertension Week of March 9, 2003/ Vol. 2 No. 10

Study: Obesity Blamed for High Rate of Hypertension in Older Children

An increase in the number of children who develop high blood pressure in their teens has been linked to the growing rate of childhood obesity, according to a study presented March 6 at the American Heart Association's annual cardiovascular disease conference in Miami.

Obese children are known to have higher blood pressure. Lead researcher Dr. Gilles Paradis, of McGill University School of Medicine in Montreal, and his colleagues wanted to further examine this issue, recognizing that the long-term consequences of excess body fat may be particularly important when starting at such a young age.

In 1999, the researchers conducted a school-based survey of 4,500 youth ages 9, 13 and 16. The children were sampled from a Department of Education list that includes all children and adolescents who attend school in Quebec.

Researchers gathered lifestyle and socio-demographic variables using a questionnaire. They measured the youth's height, weight, blood pressure and body fat. Body mass index (BMI) was calculated by a height-to-weight ratio.

Three consecutive blood pressure measures were obtained on the right arm in subjects seated and at rest for at least five minutes. The researchers used the average of the last two measures in their analysis.

Blood pressure was recorded for 3,589 youth. Systolic pressures were more elevated than expected for all age and gender groups, but more so for 13- and 16-year-olds. Height-adjusted elevated systolic pressure was found in 4.4 percent of 9-year-olds, 16.7 percent of 13-year-olds and 19.7 percent of 16-year-olds. Average systolic blood pressure rose with increasing BMI categories in all age and gender groups.

"If our results are confirmed by other investigators, there could be important public health implications," Paradis says. "These children will be tomorrow's hypertensive adults. If these levels of blood pressure persist, the number of people with hypertension could increase substantially over the next decades, with subsequent increases in hypertension-related illnesses."

Paradis said schools, parents, health professionals and policy-makers need to understand that the gravity of the obesity epidemic requires urgent and massive prevention efforts targeted at getting kids to become physically active as well as to eat a healthy and not excessive diet.

"Obesity is the No. 1 dietary disorder in North America. If this were an infectious disease, it would be deemed a public health catastrophe and authorities would be performing widespread vaccinations," Paradis said.

Other sources: American Heart Association