Utility of home doppler blood pressure measurement to minimise unnecessary investigations in children with suspected hypertension

An accurate measurement of blood pressure (BP) is essential in making a diagnosis of hypertension, however lack of reference values in children <5 years old makes out-of-office BP measurement using ambulatory blood pressure monitoring difficult in this age group. We conducted a retrospective analysis in children aged under 5 years referred to our hypertension service for suspected hypertension. We included those who underwent home doppler blood pressure measurement (HDBPM) for hypertension diagnosis confirmation, and evaluated the investigations performed for suspected hypertension before the diagnosis was confirmed using out-of-office BP measurements. Children receiving anti-hypertensive medication at the time of initial review were excluded. Fifty-five children (62% male) with a median age of 1.6 years completed HDBPM and were included. Nearly 90% of them referred for hypertension were found to be normotensive following out-of-office BP assessment using HDBPM. In these normotensive patients, different investigations for secondary hypertension, including blood tests (creatinine, renin, aldosterone, cortisol, thyroid function tests, and catecholamine levels), doppler kidney ultrasound, and echocardiograms were performed before referral, most of which yielded unremarkable results. Our finding suggested that whilst some initial investigations were essential, second-line tests for less common secondary causes of hypertension are often unnecessary before hypertension is confirmed. We recommend deferring some of these investigations in asymptomatic children until hypertension is verified by home blood pressure measurements.