Heart rate variability during sleep in children with autism spectrum disorder

Abstract

Purpose Autonomic dysfunction has been reported in autism spectrum disorder (ASD). Less is known about autonomic function during sleep in ASD. The objective of this study is to provide insight into the autonomic cardiovascular control during different sleep stages in ASD. We hypothesized that patients with ASD have lower vagal and higher sympathetic modulation with elevated heart rate (HR), as compared to typical developing children (TD). Methods We studied 21 children with ASD and 23 TD children during overnight polysomnography. Heart rate and spectral parameters were calculated for each vigilance stage during sleep. Data from the first four sleep cycles were used to avoid possible effects of different individual sleep lengths and sleep cycle structures. Linear regression models were applied to study the effects of age and diagnosis (ASD and TD). Results In both groups, HR decreased during non-REM sleep and increased during REM sleep. However, HR was significantly higher in stages N2, N3 and REM sleep in the ASD group. Children with ASD showed less high frequency (HF) modulation during N3 and REM sleep. LF/HF ratio was higher during REM. Heart rate decreases with age at the same level in ASD and in TD. We found an age effect in LF in REM different in ASD and TD. Conclusion Our findings suggest possible deficits in vagal influence to the heart during sleep, especially during REM sleep. Children with ASD may have higher sympathetic dominance during sleep but rather due to decreased vagal influence.

The Inconsistent Nature of Heart Rate Variability During Sleep in Normal Children and Adolescents

“…Furthermore, the outcome of the mixed model analysis supports that this phenomenon in HRV is independent of age in children and adolescents aged 3-13 years. Similar to results in adults (29) and children (30), we showed that the most significant drop in heart rate (increase in mean NN) occurs between sleep onset and SWS1 and continues to drop only in SWS cycles as time asleep progresses. Unlike Baharav et al who in 10 children and adolescents showed no difference in heart rate between sleep stages (31), we showed that heart rate (mean NN) was significantly different between some SWS periods and REM sleep periods across the night but that all sleep stage cycles were not the same in uninterrupted sleep.…”

A cohort study reporting normal oximetry values in healthy infants under 4 months of age using Masimo technology

“…Only artefact-free recording time (AFRT) was included in the analysis. Acceptable recordings contained at least 4 hours of data including a period of presumed REM as determined by increased heart rate variability 13. If insufficient data were obtained, a repeat recording was undertaken with the family’s agreement.…”

Autonomic dysfunction in sleep disorders: introduction to the series

“…For obvious reasons, routinely used techniques in the autonomic laboratory, such as the tilt-table test, cold pressor test or Valsalva maneuver, cannot be used while patients are sleeping. Some investigators are able to perform microneurography recordings or make catecholamine measurements on their subjects during sleep, but because virtually every polysomnography includes electrocardiography, heart rate variability has become the gold standard to study the autonomic nervous system during sleep, notwithstanding its limitations [8,17]. In this issue, Bugalho and colleagues [4] report their measurements of heart rate variability during sleep in patients with RBD; their results appear to show that these patients have reduced vagal modulation compared to patients without RBD.…”