Utilization of Ambulatory Blood Pressure Monitoring in Children and Adolescents With Hypertension

Because of the limited accuracy of office blood pressure (BP), the 2017 American Academy of Pediatrics (AAP) hypertension guidelines recommend that children with high clinic BP undergo ambulatory blood pressure monitoring (ABPM) to confirm hypertension and that clinicians strongly consider ABPM in children with risk factors for masked hypertension, like obesity and chronic kidney disease (CKD).1 Here we describe ABPM utilization in children with hypertension and children with conditions associated with masked hypertension.We performed a retrospective cohort study using aggregated, deidentified electronic health record data in the TriNetX US Research Network (www.trinetx.com), a repository of >74 million patients from 43 US health systems. Research using TriNetX was deemed exempt by the MetroHealth System Institutional Review Board.We queried TriNetX for children and adolescents aged 5 to 18 years with an ambulatory visit between 2018 and 2022 with a new International Classification of Diseases, 10th Revision (ICD-10) code for hypertension: I10, I11, I12, I13, I15, I16, or I1A. We also evaluated ABPM utilization in children with ICD-10 codes for high-risk conditions associated with masked hypertension based on AAP guidelines:1 CKD, solid organ transplant, obesity, obstructive sleep apnea, neurofibromatosis, Turner syndrome, Williams syndrome, aortic coarctation, prematurity, and diabetes mellitus.We calculated the proportion of children and adolescents with a Current Procedural Terminology code for ABPM (93784, 93786, 93788, or 93790) within 1 year of hypertension diagnosis and assessed for trends in ABPM utilization from 2018 to 2022 using the Cochran-Armitage test. We calculated the proportion of children and adolescents with each ICD-10 code associated with masked hypertension that had ever had ABPM. We evaluated ABPM utilization by patient characteristics using the χ2 test for proportions and t test for continuous variables.In sensitivity analyses, we defined hypertension as ≥2, ≥3, and ≥4 visits with encounter diagnoses for hypertension. We also evaluated utilization in children and adolescents with ICD-10 codes for elevated BP (R03.0) at ≥2 visits occurring ≥1 year apart, as persistent elevated BP is a guideline-recommended indication for ABPM.1Of 5 419 471 children and adolescents with ambulatory visits between 2018 and 2022, 42 995 had a new ICD-10 encounter diagnosis for hypertension (mean 13.4 years [SD, 3.7], 40.7% female, 56.1% white, 19.1% Black, 18.6% Hispanic). A total of 2819 children and adolescents (6.6%) with a new encounter diagnosis of hypertension completed ABPM within 1 year of diagnosis. The proportion completing ABPM within 1 year increased from 4.7% in 2018 to 8.4% in 2022 (P < .001 for trend) (Fig 1A). ABPM utilization ranged from 1.0% in 5-year-olds to 8.1% in 16-year-olds (Fig 1B). Among children and adolescents at risk for masked hypertension, 2.0% had ever completed ABPM, with utilization ranging from 1.3% in diabetes mellitus to 12.8% in transplant (Fig 1C).Patient characteristics associated with ABPM utilization included higher clinic BP at diagnosis, history of CKD, overweight or obesity, or secondary hypertension, and prescription for antihypertensive medication (Table 1). ABPM utilization was 6.7% in white patients, 7.7% in Black patients, and 11.8% in Asian patients. In sensitivity analyses, ABPM utilization within 1 year of meeting modified hypertension criteria was 13.5% in children with ≥2 visits with hypertension, 16.3% with ≥3 visits, and 18.1% with ≥4 visits. For children with persistent elevated BP based on ICD-10 code (R03.0) for ≥1 year, 13.9% completed ABPM.In this large sample of children and adolescents with hypertension encounter diagnoses, only 7.8% had ABPM. Among patients with high-risk conditions for masked hypertension, 2.0% had ABPM despite recommendations to strongly consider ABPM for these patients.1Because of the high prevalence of white coat hypertension,2 ABPM is a cost-effective step to prevent unnecessary workups, inappropriate chronic disease labeling, and overtreatment. ABPM results may also help identify which patients need further testing for secondary hypertension.3 Foregoing ABPM in patients at risk for masked hypertension can lead to missed opportunities for treatment and potentiate disparities in cardiovascular outcomes.4Implementation science efforts in adults have attempted to expand access to ABPM,5 emphasizing the need to offer ABPM in nonspecialty settings, like primary care and pharmacies.6,7 In addition to strategies to increase ABPM in pediatrics, future studies may explore alternative approaches for out-of-office BP in children, like home BP monitoring. Although used by 70% of pediatric nephrologists,8 AAP guidelines state that additional data on home BP accuracy are needed before recommending it for diagnosis.1Study limitations include use of ICD-10 codes to define hypertension and lack of information about clinician specialty or ABPM results. Given that pediatric hypertension is often unrecognized,9 we expect ABPM utilization to be substantially lower if we defined hypertension using office BP instead of ICD-10 codes. Nevertheless, our results highlight the need to explore barriers to and facilitators of ABPM to improve guideline adherence and ensure an accurate diagnosis of pediatric hypertension.