Resident Helen DeVos Children's Hospital Grand Rapids, Michigan, United States
Background: White Coat Hypertension (WCH) is defined as a hypertensive blood pressure (BP) in an office but a normal BP outside of a clinical setting (Miyashita Y, 2017). Multiple studies have shown that children with elevated BP are more likely to develop hypertension (HTN) as adults. Therefore, it is critical to evaluate an elevated BP and rule out WCH. The 2017 American Academy of Pediatrics Clinical Practice Guidelines recommend the use of an Ambulatory Blood Pressure Monitor (ABPM) as the gold standard for diagnosing HTN (Flynn J, 2017). However, an ABPM is a limited resource in some areas. Objective: This study aimed to determine an association between low diastolic BP with WCH. Our hypothesis was a low diastolic BP was associated with the diagnosis of WCH confirmed by an ABPM. Design/Methods: This is a retrospective cohort study of patients aged 6-17 years evaluated at the pediatric nephrology clinic in Helen DeVos Children’s Hospital for elevated BP without the diagnosis of HTN who received an ABPM as part of their evaluation. This was an IRB approved study. All patients had a clinic systolic BP >95th percentile. Exclusion criteria included children with congenital heart disease, chronic kidney disease, previous diagnosis of HTN, diabetes, obstructive sleep apnea, and current use of BP altering medications. Patients meeting inclusion criteria were divided into two groups: patients with WCH and patients without WCH. Descriptive statistics were used for the following variables: weight, height, body mass index (BMI), heart rate, diastolic BP, and systolic BP. Analysis of variables between the two groups done with a t-test or Kruskal Wallis test for numerical variables and Chi Square or Fishers Exact for categorical variables. Additionally, a logistic regression model for WCH was performed with the following variables: age, gender, height, systolic BP, and diastolic BP. Results: 230 patients were reviewed on initial screening and 147 patients met the inclusion criteria with an average age of 14 (27% age < 12 years, age range 7-16). Among them, 69% were diagnosed with WCH. The logistic regression model controlling for age, height, sex and systolic BP revealed a significant association between diastolic BP and the likelihood of WCH (p-value 0.046). Specifically, for every 1 unit increase in diastolic BP there is an expected 3.9% decrease in the odds of WCH.
Conclusion(s): There is a correlation with a normal or low diastolic BP with systolic HTN and increased likelihood of WCH. This information can be valuable for clinicians as a tool to triage the use of ABPMs.
