The Physiological and Clinical-Behavioral Effects of Heart Rate Variability Biofeedback in Adolescents with Autism: A Pilot Randomized Controlled Trial

Abstract

BackgroundAdolescents with autism present lower levels of cardiac vagal modulation (CVM). It was hypothesized that Heart Rate Variability Biofeedback (HRVB) increases CVM in adolescents with autism, resulting in positive effects on physiological and psychosocial parameters. It was also hypothesized that home-based HRVB training is feasible. MethodsIn a single-blind, randomized sham-controlled pilot trial, adolescents with autism performed supervised HRVB (n = 24) or sham training (n = 20). Subsequently, half of the adolescents received HRVB training at home, whereas the other subset did not practice. Physiological, cortisol and behavioral data were collected during stress-provoking assessments before and after each training period. ResultsSupervised HRVB resulted in a late increase in CVM in adolescents with autism. Heart rate increased and cortisol decreased signi cantly immediately after supervised HRVB, but none of these effects remained after follow-up. Following supervised HRVB, no signi cant change in psychosocial functioning was found. Home-based HRVB was feasible, adolescents reported lower symptoms of stress, but a signi cant decrease in compliance rate was found. ConclusionHRVB is feasible and effective in adolescents with autism given the late-emerging increases in CVM and decrease in stress symptoms.Replicating this study with a larger sample and further exploration of the working mechanisms of HRVB are recommended.

Heart rate variability biofeedback to reduce anxiety in autism spectrum disorder – a mini review

“…After duplicates were removed, 24 articles were screened for inclusion with 20 articles excluded for the reasons as listed in Figure 1 . Four remaining articles are included in this review ( 38 – 41 ).…”

“…Table 2 summarises the extracted data and critical assessment of the four included articles. Two of the four articles are published within the last two years ( 40 , 41 ), with two studies conducted in the USA ( 38 , 39 ), one in the UK ( 40 ) and one in Belgium ( 41 ). The design of the interventions in these studies varies but all comprise exploratory or pilot studies, with appropriately small sample sizes.…”

“…The most recent study reviewed in this paper, Thoen et al. ( 41 ), did employ this type of design and showed some positive effects for HRVB but also highlighted the need for more follow up to assess the longer-term effects of HRVB for ASD populations.…”

“…The importance of using additional measures of participants reactions is recommended to help elucidate the links between biofeedback and anxiety in ASD. The use of physiological assessments such as cortisol assessment ( 41 ) and the use of tests of EEG functioning ( 39 ) represent valuable methods of gathering vital information on physiological and neurological reactions.…”

“…The involvement of both users and carers in providing direct reports on symptoms and perceived stress in this population is also seen as a vital area which is needed. The use of participant reports on levels of stress and sources of stress ( 40 , 41 ) and usability reports on device function highlight how user input can help to develop future work and highlight risks and benefits of an intervention.…”