FROM PEDIATRICS
The American Academy of Pediatrics has released its long-anticipated updated guidelines on high blood pressure in children and adolescents, which includes revised BP tables based on normal-weight children only.
The document, published Aug. 21 in Pediatrics, is the first update since 2004, and recommends significant changes in both screening and treatment of hypertension (HTN).
Recognizing the strong association of overweight and obesity with elevated BP and hypertension, the guidelines committee created new normative BP tables based on normal-weight children to reduce the possibility of bias in the tables. These include systolic and diastolic BP values for age, sex, height, and height percentile, based on measurements from around 50,000 children and adolescents, but exclude individuals with a body mass index (BMI) at or above the 85th percentile. As a result, the BP values are several millimeters of mercury lower, compared with those in the previous version of the guidelines (Pediatrics. 2017 Aug 21. doi: 10.1542/peds.2017-1904 )
The guidelines also include a simplified screening table for initial screening, which lists the 90th percentile BP for age and sex, for children at the fifth percentile of height. These values give the table a negative predictive value of greater than 99%, although the committee stressed that the table should only be used for screening, and not for diagnosis.
“To diagnose elevated BP or HTN, it is important to locate the actual cutoffs in the complete BP tables because the [systolic] BP and [diastolic] BP cutoffs may be as much as 9 mm Hg higher depending on a child’s age and length or height,” wrote Joseph T. Flynn, MD, and his colleagues on the AAP subcommittee on screening and management of high blood pressure in children.
To ensure consistency between these guidelines and the 2017 adult guidelines from the American Heart Association and American College of Cardiology, the committee also decided to replace the term “prehypertension” with “elevated blood pressure.”
Similarly, the committee recommended adopting revised stage 1 and stage 2 HTN criteria, to enable the staging scheme for children aged 13 years and over to “seamlessly interface” with the 2017 AHA and ACC adult guidelines.
“There are still no data to identify a specific level of BP in childhood that leads to adverse [cardiovascular] outcomes in adulthood,” the committee wrote. “Therefore, the subcommittee decided to maintain a statistical definition for childhood HTN.”
In terms of screening children for hypertension, the guidelines review committee made the recommendation that BP be measured annually in children and adolescents aged 3 years or above. However, if the child is at greater risk of hypertension because of obesity, medications known to increase BP – such as stimulants for ADHD – renal disease, a history of aortic arch obstruction or coarctation, or have diabetes, they should have their BP measured at every health care encounter.
They also stressed it was important to take more than one measurement over time before diagnosing HTN, and to use appropriately-sized cuffs to ensure an accurate measurement.
If a child or adolescent has confirmed auscultatory BP readings at or above the 95th percentile on three different visits, this justifies a diagnosis of HTN, they wrote.
The committee strongly recommended the routine performance of ambulatory BP monitoring in patients with high-risk conditions, such as diabetes, secondary hypertension, or renal disease, to look for abnormal circadian BP patterns that might point to an increased risk of target organ damage.
They also issued revised recommendations on when to perform echocardiography in children newly diagnosed with HTN.
“It is recommended that echocardiography be performed to assess for cardiac target organ damage (left ventricular mass, geometry, and function) at the time of consideration of pharmacologic treatment of HTN,” they wrote, suggesting repeat echocardiography could be used to monitor target organ damage at 6-12 month intervals.
They offered a revised definition of left ventricular HTN as a left ventricular mass greater than 51 g/m2.7 for children and adolescents older than 8 years (greater than 115 g/body surface area for boys and greater than 95 g/body surface area for girls).
While previous treatment recommendations used a treatment target of a systolic and diastolic BP below the 95th percentile in children without chronic kidney disease, new evidence prompted a revised recommendation of a target either below the 90th percentile or less than 130/80 mm Hg.
“Longitudinal studies on BP from childhood to adulthood that include indirect measures of [cardiovascular] injury indicate that the risk for subsequent [cardiovascular disease] in early adulthood increases as the BP level in adolescence exceeds 120/80 mm Hg,” they wrote. “In addition, there is some evidence that targeting a BP less than 90th percentile results in reductions in [left ventricular mass index] and prevalence of [left ventricular hypertrophy].”
In hypertensive children and adolescents who have failed lifestyle modifications, such as physical activity, weight loss, and stress reduction (particularly those who have left ventricular hypertrophy, symptomatic HTN, or stage 2 HTN without a clearly modifiable factor such as obesity), pharmacologic treatment with an angiotensin-converting enzyme inhibitor, angiotensin receptor blocker, long-acting calcium channel blocker, or thiazide diuretic is indicated, according to the revised guidelines.
The guidelines were supported by the American Academy of Pediatrics and endorsed by the American Heart Association. No conflicts of interest were declared.
