Children who may have high blood pressure can benefit from 24-hour blood pressure monitoring

The American Heart Association now recommends 24-hour blood pressure monitoring for certain children and adolescents suspected of having high blood pressure or a condition that causes unreliable readings at the doctor’s office.

The statement, published in Hypertension: Journal of the American Heart Association, is expert-opinion driven and not evidence-based. That’s because studies relating 24-hour monitoring in children to hard outcomes like heart attack and stroke are not yet available.

High blood pressure, also called hypertension, is a major risk factor for heart attack and stroke in adults.

“The most important take-home message is that clinical hypertension can be identified in children and adolescents and is associated with organ damage even at young ages. Therefore, accurate diagnosis and early treatment is essential,” said Elaine Urbina, M.D., chair of the statement writing group and director of preventive cardiology at Cincinnati Children’s Hospital Medical Center in Ohio.

“There is now sufficient experience with ambulatory blood pressure monitoring (ABPM) to recommend its use in paediatric patients to assist in diagnosing hypertension,” she said.

In ABPM, the patient wears a blood pressure cuff attached to a portable data recorder during daily activities and sleep. At least once each hour the cuff inflates and the device records a blood pressure reading.

The American Heart Association recommends using ABPM to rule out white coat hypertension (high levels at the doctor’s office but normal levels at home) and masked hypertension (normal levels at the clinic but high blood pressure at home). It can also be useful for evaluating the effectiveness of high blood pressure medications, observing whether blood pressure decreases at night during sleep; and evaluating apparent drug-resistant hypertension.

Researchers found white coat hypertension in 22 percent to 88 percent of children studied.

“Ambulatory monitoring is likely to be most useful in children whose office blood pressure readings are up to 10 percent over the highest acceptable reading, as children with very high readings (more than 10 percent higher than the highest reading) were more likely to have true high blood pressure,” Urbina said.

Studies have shown ABPM is superior to in-clinic monitoring at predicting cardiovascular death and disability in adults. The writing committee said the test’s predictive ability is enhanced because it records blood pressure changes throughout the 24-hour period, including the presence or absence of “dipping” (when blood pressure drops a certain percentage during sleep). “Non-dipping” indicates a risk of organ damage, like left heart thickening, due to high blood pressure.

Because the use of ABPM in children is relatively new, there is little data on the technology’s predictive ability. But the committee recommends ABPM based on evidence of its usefulness in specific situations.

“The global obesity epidemic is linked with increasing blood pressure levels in young people,” Urbina said. “In addition, blood pressure levels at the higher end of the spectrum in the early years tend to track into adulthood and might lead to the development of hypertension.

According to the statement, an estimated one in four adults throughout the world has high blood pressure, which contributes to 49 percent of ischemic heart disease and 62 percent of strokes, globally.

“These guidelines help paediatric healthcare providers to understand the use of ABPM in monitoring children’s blood pressure,” Urbina said. “A standard technique advocated by a national organisation like the American Heart Association is reassuring to parents who want to be sure that their children are receiving consistent, high-quality care.”

The statement includes recommendations for doctors on choosing an ABPM machine and caring for the equipment, as well as guidelines on fitting cuffs to paediatric patients. It also suggests that ABPM be performed only by personnel trained to use the device and interpret its data in children.

While the American Heart Association recently recommended home monitoring for adults with high blood pressure, the statement said ABPM had better diagnostic specificity for children compared to home measurement.

Furthermore, the association supports children adopting a healthy lifestyle — including exercise, maintaining ideal body weight, and a diet low in sodium and rich in potassium, calcium and magnesium — to help prevent high blood pressure in adulthood.

(Source: Hypertension: American Heart Association: August 2008)