The reliability of a breath‐hold protocol to determine cerebrovascular reactivity in adolescents

Abstract

Purpose: Cerebrovascular reactivity (CVR) is impaired in adolescents with cardiovascular disease risk factors. A breath-hold test is a noninvasive method of assessing CVR, yet there are no reliability data of this outcome in youth. This study aimed to assess the reliability of a breath-hold protocol to measure CVR in adolescents. Methods: Twenty-one 13 to 15 year old adolescents visited the laboratory on two separate occasions, to assess the within-test, within-day and between-day reliability of a breath-hold protocol, consisting of three breath-hold attempts. CVR was defined as the relative increase from baseline in middle cerebral artery mean blood velocity following a maximal breath-hold of up to 30 seconds, quantified via transcranial Doppler ultrasonography. Results: Mean breath-hold duration and CVR were never significantly correlated (r < .31, P > .08). The within-test coefficient of variation for CVR was 15.2%, with no significant differences across breath-holds (P = .88), so the three breath-hold attempts were averaged for subsequent analyses. The within-and between-day coefficients of variation for CVR were 10.8% and 15.3%, respectively. Conclusions: CVR assessed via a three breath-hold protocol can be reliably measured in adolescents, yielding similar within-and between-day reliability. Analyses revealed that breath-hold length and CVR were unrelated, indicating the commonly reported normalization of CVR to breath-hold duration (breath-hold index) may be unnecessary in youth. K E Y W O R D S cerebral blood flow, endothelial function, hypercapnic stimulus, reproducibility, transcranial Doppler ultrasound, youth 1 | INTRODUCTION Cerebrovascular reactivity (CVR) refers to the ability of the human brain to modulate cerebral blood flow in response to changes in stimuli, such as the partial pressure of arterial carbon dioxide (PaCO 2). Impairments in CVR are an important hallmark for cerebrovascular disease (CVD) progression. Research highlights that impairments in CVR in adults is associated with Alzheimer's disease, 1 neurocognitive decline, 2 stroke, 3,4 and independently predicts future CVD events in patients with CVD risk factors. 5 Impairments in CVR are present in

The within‐ and between‐day reliability of cerebrovascular reactivity using traditional and novel analytical approaches

“…When analysed in this way, the results of the current study demonstrated acceptable within-and between-day reliability (8.1-11.7%) using the MCAv peak response. This compares favourably to similar variables investigating cerebrovascular regulation via TCD using breath hold-induced CVR or as the percentage increase in MCAv without normalising to the P ETCO 2 stimulus (Koep et al, 2020;McDonnell et al, 2013). It therefore seems that expressed as an absolute CVR using the peak MCAv is the most reliable method to assess CVR.…”

Cerebral blood flow regulation is not acutely altered after a typical number of headers in women footballers

“…Cerebrovascular reactivity to hypercapnia and hypocapnia was inferred using a repeated breath holding and separate hyperventilation protocol, respectively. Such an approach is advocated as an alternative to inhalation of higher concentrations of CO 2 ( 31 – 33 ), and we replicated a breath holding and hyperventilation protocol which is sensitive to alterations post concussion ( 34 ). Participants were coached to perform both techniques prior to any data collection, with particular instruction to avoid the Valsalva maneuver during breath holding.…”

Validation of the Openwater wearable optical system: cerebral hemodynamic monitoring during a breath-hold maneuver

“…10,100,101 The BHI values reported here are within the range of what is expected in a healthy young cohort but is higher than has been reported in some healthy cohorts. [102][103][104][105] The difference may be explained by the fact that some groups identify the maximum CBF at the moment the breath-hold ends, 41,106 which underestimates the BHI because the maximum CBF is expected to occur a few seconds after the completion of the breathhold. 100,106,107 Another consideration is the focus on a single breath-hold, rather than averaging multiple breath-holds as is performed by some groups.…”