Varying blood pressure in children: a diagnostic quandary interpreting the Fourth Report.

Fourth Report guidelines on pediatric blood pressure (BP) are not clear when defining hypertension in children as "an average systolic BP and/or diastolic BP ≥ 95th percentile for gender, age, and height on ≥ 3 occasions." We aimed to determine the prevalence of pediatric hypertension in a screening population based on two different guideline interpretations. Prevalence of hypertension among 2094 students at four Houston area schools was calculated based on the summation or sustained model definition from Fourth Report guidelines. Summation hypertension definition required the single average of the BPs recorded across three visits to be elevated. Sustained hypertension definition required BP at each of three visits to be elevated. Hypertension prevalence by the summation method was 7%, whereas sustained prevalence was only 3.3%. Nearly a quarter of students had varying BP and were not classifiable by the sustained method but most would be classified as normal or prehypertensive by the summation method. The prevalence of hypertension among adolescents doubled depending on the interpretation of Fourth Report guidelines. Although methods in research studies can be clearly examined on publication of results, it is unknown which interpretation method is being used in clinical practice.