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.
Methods
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.1
Results
Of 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).
FIGURE 1.
(A) Proportion of patients aged 5 to 18 years with incident hypertension based on a new ICD-10 code at an ambulatory visit that had ABPM within 1 year of their hypertension encounter diagnosis, by year of initial encounter diagnosis. (B) Proportion of patients with an incident hypertension ICD-10 encounter diagnosis that had ABPM within 1 year of their hypertension encounter diagnosis, by age at initial encounter diagnosis. (C) Proportion of patients aged 5 to 18 years with each ICD-10 encounter diagnosis at an ambulatory visit between 2018 and 2022 that have ever had ABPM. In Fig 1C, we identified high-risk conditions associated with masked hypertension based on the 2017 American Academy of Pediatrics guideline using the following encounter diagnoses ICD-10 codes: chronic kidney disease stages 2 to 5 (N18.2, N18.3, N18.31, N18.32, N18.4, N18.5, or N18.6), solid organ transplant (Z94.0, Z94.1, Z94.2, Z94.3, Z94.4, Z94.82, Z94.83), obesity (E66.0, E66.1, E66.2, E66.8, or E66.9), obstructive sleep apnea (G47.33), genetic conditions (neurofibromatosis [Q85.0], Turner syndrome [Q96.0], Williams syndrome [Q93.82]), coarctation of the aorta (Q25.1), prematurity ≤32 weeks gestation (P07.2, P07.31, P07.32, P07.33, P07.34, or P07.35), and diabetes mellitus (E08, E09, E10, E11, E12, E13). Of note, the 2017 guideline does not specify the stage of CKD or degree of prematurity for whom ABPM is indicated, but we included CKD stages 2 to 5 and prematurity ≤ 32 weeks to capture a more severe phenotype of patients who may be more likely to undergo ABPM. NF, neurofibromatosis; OSA, obstructive sleep apnea; wga, weeks gestational age.
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.
TABLE 1.
Utilization of ABPM by Characteristics of Patients Aged 5 to 18 Years With New ICD-10 Encounter Diagnosis of Hypertension at an Ambulatory Visit Between 2018 and 2022 (N = 42 995)
| Characteristica | Had ABPM (N = 3344) | No ABPM (N = 39 651) | P b |
|---|---|---|---|
| Age at hypertension diagnosis, years (SD) | 13.5 (3.2) | 13.3 (3.7) | .002 |
| Sex, N (%) | |||
| Female | 1173 (6.7) | 16 342 (93.3) | <.001 |
| Male | 2171 (8.7) | 22 847 (91.3) | |
| Unknown | 0 (0.0) | 462 (100.0) | |
| Race, N (%) | |||
| White | 1606 (6.7) | 22 525 (93.3) | <.001 |
| Black | 628 (7.7) | 7574 (92.3) | |
| Unknown race | 468 (9.2) | 4645 (90.8) | |
| Other race | 454 (11.7) | 3410 (88.3) | |
| Asian | 159 (11.8) | 1194 (88.2) | |
| American Indian or Alaska Native | 17 (10.3) | 148 (89.7) | |
| Native Hawaiian or other Pacific Islander | 12 (7.2) | 155 (92.8) | |
| Ethnicity, N (%) | |||
| Hispanic or Latino | 809 (10.1) | 7185 (89.9) | <.001 |
| Not Hispanic or Latino | 2297 (7.7) | 27 505 (92.3) | |
| Unknown Ethnicity | 238 (4.6) | 4961 (95.4) | |
| Systolic BP at hypertension diagnosis, mean (SD) | 141 (27.0) | 126 (18.9) | <.001 |
| Diastolic BP at hypertension diagnosis, mean (SD) | 88 (32.8) | 76 (15.6) | <.001 |
| Comorbidities by ICD-10 code, N (%) | |||
| Chronic kidney disease (N18) | 392 (11.7) | 2961 (88.3) | <.001 |
| No chronic kidney disease | 2952 (7.4) | 36 690 (92.6) | |
| Overweight or obesity (E66) | 1694 (10.3) | 14 827 (89.7) | <.001 |
| No overweight or obesity | 1650 (6.2) | 24 824 (93.8) | |
| Secondary hypertension (I15) | 654 (15.6) | 3536 (84.4) | <.001 |
| No secondary hypertension | 2690 (6.9) | 36 115 (93.1) | |
| Antihypertensive medication prescribed within 1 year after hypertension diagnosis, N (%)c | |||
| Angiotensin converting enzyme inhibitor | 719 (15.2) | 4020 (84.8) | <.001 |
| Amlodipine | 451 (13.8) | 2818 (86.2) | <.001 |
| Thiazide diuretic | 94 (9.8) | 861 (90.2) | .02 |
| Angiotensin receptor blocker | 116 (14.3) | 694 (85.7) | <.001 |
| Echocardiogram completed within 1 year after hypertension diagnosis, N (%) | 1242 (13.5) | 7984 (86.5) | <.001 |
a We report row percentages to examine differences in utilization by patient characteristics.
b We compared groups using the χ2 test for proportions and t test for continuous variables.
c The medications listed reflect first-line pharmacologic treatment options based on the 2017 American Academy of Pediatrics guideline: angiotensin converting enzyme inhibitor, long-acting calcium channel blocker, thiazide diuretic, or angiotensin receptor blocker.
Discussion
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.1
Because 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.4
Implementation 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.1
Study 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.
Glossary
- AAP
American Academy of Pediatrics
- ABPM
ambulatory blood pressure monitoring
- BP
blood pressure
- CKD
chronic kidney disease
- ICD
International Classification of Diseases
Footnotes
Dr Nugent conceptualized and designed the study, collected data, conducted the initial analyses, and drafted the initial manuscript; Dr Kaelber conceptualized and designed the study, supervised data collection and analysis, and interpreted the data; and all authors critically reviewed and revised the manuscript, approved the final manuscript as submitted, and agree to be accountable for all aspects of the work.
FUNDING: Dr Nugent is funded by a Yale Physician Scientist Development Award, Academic Pediatric Association Young Investigator Award, and American Heart Association Career Development Award 24CDA1051185. This publication was made possible by CTSA grant UL1 TR001863 from the National Center for Advancing Translational Science. This project was supported in part by the Clinical and Translational Science Collaborative of Northern Ohio, which is funded by the National Institutes of Health, National Center for Advancing Translational Sciences, Clinical and Translational Science Award grant UM1TR004528. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.
CONFLICT OF INTEREST DISCLOSURES: The authors have no conflicts of interest relevant to this article to disclose.
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