Focus intensified on child and teen health
■ Legislation is introduced regarding childhood obesity while new guidelines urge physicians to check young patients' blood pressure.
By Susan J. Landers — Posted July 12, 2004
Washington -- Children as young as 3 should have their blood pressure checked as part of a routine examination, according to new federal guidelines, so that corrective action can be taken early to rein in higher than optimal readings.
"The long-term health risks for hypertensive children and adolescents can be substantial," warned Bonita Falkner, MD, professor of medicine and pediatrics at Jefferson Medical College of Thomas Jefferson University in Philadelphia.
Blood pressure has been on the rise among children and teens, and research shows that for every 1 mm Hg to 2 mm Hg rise in systolic blood pressure, children face a 10% greater risk of developing hypertension as young adults.
Dr. Falkner chaired the National High Blood Pressure Education Program Working Group that updated the 1996 hypertension guidelines for children, and she would like to see all physicians measure and plot out the blood pressure readings of their young patients just as they measure and plot their heights and weights.
The updated guidelines, part of the Fourth Report on the Diagnosis, Evaluation and Treatment of High Blood Pressure in Children and Adolescents, were scheduled for publication in the July issue of Pediatrics and were previewed last spring at meetings of the Pediatric Academic Societies and the American Society of Hypertension. While the definition of hypertension for children is unchanged, the new guidelines introduce a "prehypertensive" category to serve as an early alert. Adult guidelines updated last year also included such a classification.
Young children who fall into this category are those whose average systolic or diastolic blood pressures fall between the 90th and 95th percentiles on published blood pressure tables. Prehypertensive adolescents have blood pressures greater than 120/80 mm Hg, the same as the adult prehypertensive category.
In adults, the systolic and diastolic numbers define hypertension but the vast range in body sizes, ages and heights among children necessitated blood pressure tables for children based on gender, age and weight to avoid incorrectly classifying those who are either very tall or very short.
As with their older counterparts, weight control is key to lowering blood pressure in children. "Linked with that are recommendations to avoid a sedentary lifestyle; reduce the intake of high-salt foods; and shift to fruits, vegetables and low-fat dairy products," Dr. Falkner said.
Meanwhile, new Senate legislation works on a parallel track to take aim at childhood obesity, which, like hypertension, is a risk factor for diabetes and cardiovascular disease.
Senate Majority Leader Bill Frist, MD, (R, Tenn.) and Sen. Ron Wyden, (D, Ore.), introduced a bill June 21 designed to encourage school-age children to increase their physical activity and choose healthier foods.
The Childhood Obesity Reduction Act would recognize schools that implement plans to help children control their weight and establish a Congressional Council to Combat Childhood Obesity. More than 15% of American children and teens ages 6 to 19 are overweight, according to recent data.
The federal guidelines also recommend evaluating the cholesterol levels of children with elevated blood pressure, screening them for diabetes and checking for target organ damage. "We now have enough evidence that children with hypertension can show signs of injury from the high blood pressure," Dr. Falkner said.
Pediatric patients with established hypertension should undergo echocardiography assessment for left ventricular hypertrophy, the most prominent evidence of target organ damage, according to the guidelines.
Physicians are also advised to take a sleep history of young patients as there is known to be an association between hypertension, sleep apnea and obesity.
The preferred method of measuring blood pressure in children is auscultation, and elevated readings must be confirmed on repeated visits. Care also must be taken that the cuff used for children is the proper size: wide enough to encircle 40% to 50% of the circumference of the arm. Physicians who aren't accustomed to measuring blood pressure in children sometimes use too small a cuff, Dr. Falkner said.
Doctors also might need to prescribe medication for children who have stage-two hypertension -- or blood pressure 5 mm Hg above the 99th percentile on the chart -- which doesn't respond to diet and exercise; or for those who have kidney disease, diabetes or other comorbid condition.
Dr. Falkner suggests trying any of the major classes of antihypertensive medication to see which works best. Several have been tested on children under new requirements of the 2003 Pediatric Research Equity Act, a law applauded by pediatricians.
Drug testing on children has brought about labeling changes for 70 drugs so far, said Murray A. Lumpkin, acting deputy commissioner for Internal and Special Programs at the Food and Drug Administration.
There also were some surprising findings among the first drugs to be tested, said Richard Goorman, MD, chair of the American Academy of Pediatrics Committee on Drugs. While no safety risks were uncovered, there were some "therapeutic risks," he said.
For example, "It turns out that kids need about 30% more Neurontin, or gabapentin, pound for pound for pain relief than do adults," Dr. Goorman said. "Here were kids being treated for pain with Neurontin who weren't doing as well as adults. They were being underdosed."