Many kids classified as having hypertension might be misdiagnosed due to lack of repeat blood pressure measurement during the same visit, a study suggested.
In the cohort study of patients ages 3 to 17 years enrolled in a Kaiser Permanente Southern California health plan since 2007, 24.7% had a blood pressure reading in the hypertensive range, defined by the 95th percentile or above (n=186,732).
Only about one-fifth of them had a repeat measurement (n=30,565), Corinna Koebnick, PhD, of Kaiser Permanente Southern California in Pasadena, and colleagues reported online in the Journal of Clinical Hypertension.
Among those who did have two blood pressure readings, half turned out to have an average blood pressure in normal range, meaning they would have been false positives if the initial measurement had been taken on its own. These are the children that avoided a potentially unnecessary follow-up visit, according to the researchers.
In contrast, just 1.2% of pediatric patients had false negatives, or a lower initial reading and then a higher one on repeat.
New pediatric hypertension guidelines released in 2017 call for a repeat measure when office blood pressure is high.
“The recommendation to repeat high blood pressure during the same visit needs to be emphasized because it saves unnecessary follow-up visits,” Koebnick and colleagues said. Electronic medical records from 2012 to 2015 provided the data for their study.
As for those whose initial blood pressure reading exceeded the 99th percentile by at least 5 mm Hg and was tested a second time, 65.0% had an average blood pressure below the 95th percentile and would have been false positives if not for repeat measurement.
“Our results also indicate that if asymptomatic youth are screened and followed up as recommended within 3 months, hypertension was confirmed in only a small proportion of youth. About 2% of youth with an initial visit indicating hypertension stage I, and 11% of youth with an initial visit indicating hypertension stage II continued to have high blood pressure during their follow-up visits,” according to Koebnick’s group.