Blood Pressure Classification Status in Children With CKD Following Adoption of the 2017 American Academy of Pediatrics Guideline

Abstract

Rationale & objective: Accurate detection of hypertension is crucial for clinical management of pediatric chronic kidney disease (CKD). The 2017 American Academy of Pediatrics (AAP) clinical practice guideline for childhood hypertension included new normative blood pressure (BP) values and revised definitions of BP categories. In this study, we examined the effect of applying the AAP guideline's normative data and definitions to the Chronic Kidney Disease in Children (CKiD) cohort compared with use of normative data and definitions from the 2004 Fourth Report on the Diagnosis, Evaluation, and Treatment of High Blood Pressure in Children and Adolescents.

Study design: Observational cohort study.

Setting & participants: Children and adolescents in the CKiD cohort.

Exposure: Clinic BP measurements.

Outcome: BP percentiles and hypertension stages calculated using the 2017 AAP guideline and the Fourth Report from 2004.

Analytical approach: Agreement analysis compared the estimated percentile and prevalence of high BP based on the 2017 guideline and 2004 report to clinic and combined ambulatory BP readings.

Results: The proportion of children classified as having normal clinic BP was similar using the 2017 and 2004 systems, but the use of the 2017 normative data classified more participants as having stages 1-2 hypertension (22% vs 11%), with marginal reproducibility (κ=0.569 [95% CI, 0.538-0.599]). Those identified as having stage 2 hypertension by the 2017 guideline had higher levels of proteinuria compared with those identified using the 2004 report. Comparing use of the 2017 guideline and the 2004 report in terms of ambulatory BP monitoring categories, there were substantially more participants with white coat (3.5% vs 1.5%) and ambulatory (15.5% vs 7.9%) hypertension, but the proportion with masked hypertension was lower (40.2% vs 47.8%, respectively), and the percentage of participants who were normotensive was similar (40.9% vs 42.9%, respectively). Overall, there was good reproducibility (κ=0.799 [95% CI, 0.778-0.819]) of classification by ambulatory BP monitoring.

Limitations: Relationship with long-term progression and target organ damage was not assessed.

Conclusions: A greater percentage of children with CKD were identified as having hypertension based on both clinic and ambulatory BP when using the 2017 AAP guideline versus the Fourth Report from 2004, and the 2017 guideline better discriminated those with higher levels of proteinuria. The substantial differences in the classification of hypertension when using the 2017 guideline should inform clinical care.

Keywords: Ambulatory blood pressure monitoring (ABPM); BP threshold; blood pressure (BP); childhood hypertension; chronic kidney disease (CKD); diagnostic criteria; guideline implementation; hypertension prevalence; hypertension staging; normative data; pediatric BP; pediatric nephrology.

Figure 1.

Differences between 2017 AAP CBG blood pressure percentiles and 2004 Fourth Report percentiles plotted on the 2004 Fourth Report percentiles, stratified by systolic blood pressure (SBP) and diastolic blood pressure (DBP), with nonparametric lowess splines with 95% confidence bands. The horizontal reference line at 0 indicates no difference between 2017- and 2004-calculated percentiles.

Figure 2.

Description of agreement between BP stages based on 2004 Fourth Report and 2017 AAP CPG (n= 6031 person-visits from 1041 participants). Resampling cross-sectional estimate of Kappa statistic= 0.569 (95% CI: 0.538, 0.599).