METHODS TO RECTIFY DISCREPANCIES WITH ADULT BLOOD PRESSURE GUIDELINES

Abstract

Objective: The American Academy of Pediatrics (AAP) guidelines for screening and managing high blood pressure (BP) for children and adolescents are commonly used for Australian children. These were updated in 2017 to remain consistent with recommendations for adults in the United States (hypertension defined as >=130/80mmHg), which differ from guidelines for Australian adults (>=140/90mmHg). We sought to investigate the applicability of the AAP guidelines to define BP thresholds for Australian children. Design and method: The West Australian Pregnancy Cohort (Raine) Study has followed since birth a cohort of 2868 children born between 1989–1991. BP was measured at 3/5/8/10/14/17 years, in the seated position after 5 minutes rest, using an oscillometric sphygmomanometer (Dinamap™). Three readings were taken every 2 minutes until the 10-year visit, and subsequently 6 readings every 2 minutes, with the first measurement discarded and mean of following results calculated to give the BP value. Centile curves were constructed by the LMS method, adjusted for height and stratified by sex, and then compared to the published AAP centile curves. In this analysis we focus on systolic BP (SBP). Results: 2202 participants were included, contributing 7850 observations (1127 males, 51.2%). The 95th SBP centile according to the fitted curves for a child on the 50th height centile are displayed in Fig. 1, along with equivalent AAP curves. The fitted were higher than the AAP curves for both sexes in early and mid-childhood, before converging in adolescence for females but not males in whom the fitted curve approached 140mmHg at 18 years. Comparing absolute BP thresholds, 13.5% of children had an SBP >=130mmHg between 14 and 18 years of age, but only 3.0% had an SBP >=140mmHg. Conclusions: Using data from Australian children and adolescents to define the threshold for hypertension led to curves more congruous with current Australian adult hypertension guidelines. Sex stratification better represents physiologic changes in BP, but again leads to inconsistencies between paediatric and adult guidelines. A better method would be to develop net-benefit or risk-based guidelines based on future clinical events or phenotypes, which we aim to do in future work.