Using Ambulatory Blood Pressure Monitoring for Hypertension in Pediatric-Aged Patients
Saturday, February 04, 2012
By recent estimates, nearly 4 percent of pediatric-aged patients have hypertension, indicating a blood pressure greater than the 95th percentile for patients of similar age, sex and height.
Photo: James Prebis, MD
A staggering 10 percent of pediatric-aged patients have prehypertension, with blood pressure falling between the 90th and 95th percentiles, marked by a high probability of becoming hypertensive without intervention. Although a vast majority of pediatric patients and their families are unaware that this condition can affect children and adolescents, it has become a significant issue within the pediatric population.
In adults, hypertension is often referred to as “the silent killer,” leading to heart attack, stroke or kidney failure without warning symptoms. In pediatric-aged patients, “the silent thief” is more appropriate, as it has the potential to steal a young patient’s long-term health. The proof is in the nearly 40 percent of pediatric-aged hypertensive patients that show a thickening of the heart muscle on echocardiograms, as well as thickening of the wall of the carotid artery, which is related to both elevated lipids and hypertension.
According to guidelines from the National Heart, Lung and Blood Institute, children should have their blood pressure checked during medical visits beginning at the age of three. However, through the introduction of ambulatory blood pressure monitoring (ABPM), we find that 40 to 50 percent of those pediatric-aged patients presenting with high blood pressure during these visits actually have what is referred to as “white coat hypertension,” meaning that a child is anxious or nervous due to the clinical setting, causing an elevated blood pressure.
ABPM, an out-of-office measurement more commonly used to identify potentially hypertensive adults, involves attaching a blood pressure cuff to the patient’s arm, which is attached to a small device (only slightly larger than a pager) worn on the waistband. The device is programmed to check the blood pressure for 24 hours, roughly every 20 minutes during the day and every 45 minutes during sleep. While an individual sleeps, blood pressure should drop at least 10 percent. If this does not occur, or if blood pressure rises during sleep, the patient is at an increased risk for significant long-term cardiovascular complications.
As opposed to the standard measure of blood pressure in an office setting, ABPM measures the patient’s blood pressure throughout the day and night, while they are at home or school, and performing normal daily activities. This provides a more accurate assessment of their blood pressure fluctuations and helps to identify white coat hypertension vs. prehypertension or hypertension.
The prevalence of obesity in children and adolescents has tripled over the last 30 years. In the past, hypertension in pediatric patients was often due to an underlying organ dysfunction (secondary hypertension), but today the most common cause of pediatric hypertension is obesity.
The fundamental goal of ABPM is to identify patients with prehypertension or hypertension as early as possible, and intervene appropriately to reduce the risk of long-term side effects and complications. The initial treatment for all patients with high blood pressure is healthy lifestyle modifications, which include weight loss and at least 30 to 60 minutes of daily exercise, which may simply be playing for children. Additionally, following a low-sodium, high-potassium diet that also limits added fats and sugar, such as the National Heart, Lung and Blood Institute’s DASH diet (Dietary Approaches to Stop Hypertension), is recommended. In fact, the DASH diet is considered an ideal eating plan for all individuals, despite blood pressure concerns.
For those children who require antihypertensive medications, ABPM can reveal how effective the medication is at controlling the patient’s blood pressure throughout the day and night.
Ultimately, it is the role of a physician to provide preventive care for their patients, and effectively monitoring the blood pressure of pediatric-aged patients is vital to identify and reduce risk factors that begin in childhood and carry into adulthood. When a pediatric-aged patient shows persistent elevated blood pressure readings on three separate occasions, ABPM is likely the next best step in their evaluation.
Dr. James Prebis is a board-certified pediatric nephrologist and director of the Pediatric Hypertension Center at Akron Children’s Hospital.
MD News January/February 2012, Cleveland/Akron/Canton