Maturation of the Cardiac Autonomic Nervous System Activity in Children and Adolescents

Abstract

Background Despite the increasing interest in cardiac autonomic nervous activity, the normal development is not fully understood. The main aim was to determine the maturation of different cardiac sympathetic‐(SNS) and parasympathetic nervous system (PNS) activity parameters in healthy patients aged 0.5 to 20 years. A second aim was to determine potential sex differences. Methods and Results Five studies covering the 0.5‐ to 20‐year age range provided impedance‐ and electrocardiography recordings from which heart rate, different PNS‐parameters (eg, respiratory sinus arrhythmia) and an SNS‐parameter (pre‐ejection period) were collected. Age trends were computed in the mean values across 12 age‐bins and in the age‐specific variances. Age was associated with changes in mean and variance of all parameters. PNS‐activity followed a cubic trend, with an exponential increase from infancy, a plateau phase during middle childhood, followed by a decrease to adolescence. SNS‐activity showed a more linear trend, with a gradual decrease from infancy to adolescence. Boys had higher SNS‐activity at ages 11 to 15 years, while PNS‐activity was higher at 5 and 11 to 12 years with the plateau level reached earlier in girls. Interindividual variation was high at all ages. Variance was reasonably stable for SNS‐ and the log‐transformed PNS‐parameters. Conclusions Cardiac PNS‐ and SNS‐activity in childhood follows different maturational trajectories. Whereas PNS‐activity shows a cubic trend with a plateau phase during middle childhood, SNS‐activity shows a linear decrease from 0.5 to 20 years. Despite the large samples used, clinical use of the sex‐specific centile and percentile normative values is modest in view of the large individual differences, even within narrow age bands.

Autism Spectrum Disorder in Children Is Not Associated With Abnormal Autonomic Nervous System Function: Hypothesis and Theory

“…Despite numerous assertions in the literature to the contrary, the absolute values of baseline RSA of children with ASD are almost all within the normal range. The wide range of normal RSA values in children was documented by Harteveld et al, who reported on 4,822 children aged 0.5–20 years ( 25 ). Harteveld et al ( 25 ) used the peak-valley method, measuring RSA by subtracting the shortest inter-beat interval during inhalation from the longest inter-beat interval during exhalation, and found that for 328 children aged 13–15, the RSA ranged from 18.7 to 186.7 ms (2.5–97.5 percentile), hence a very wide normal range.…”

“…The wide range of normal RSA values in children was documented by Harteveld et al, who reported on 4,822 children aged 0.5–20 years ( 25 ). Harteveld et al ( 25 ) used the peak-valley method, measuring RSA by subtracting the shortest inter-beat interval during inhalation from the longest inter-beat interval during exhalation, and found that for 328 children aged 13–15, the RSA ranged from 18.7 to 186.7 ms (2.5–97.5 percentile), hence a very wide normal range. In a personal communication, Harteveld calculated the range of RSA values (2.5–97.5 percentile) in 99 typically developing children, aged 4–18, to be 4.5–8.8 ln(ms 2 ) ( Table 1 ).…”

“…Vaughan van Hecke et al ( 24 ) reported baseline RSA to be significantly lower in an ASD group compared to typically developing controls. While statistically significant, the RSA values in the group of children with ASD fall within the normal range of control values ( 25 ), and most values also fall within the experimental control group values ( Figure 1 ); hence their conclusion that “ASD patients have a lower baseline RSA” is not correct. The only valid conclusion is that a small subgroup of patients with RSA values falls outside the control group's confidence levels (or average ± one standard deviation range).…”

“…SD2 is also highly correlated with RMSSD and should therefore not be used as a sympathetic descriptor ( 82 , 83 ). It is important to note that if HRV parameters are used to study co-morbidities with autonomic dysfunction, one has to account for covariates that affect autonomic function such as age, sex, body posture at the time of recording, and time of day of the recording ( 25 ). Several studies provide evidence that HRV parameters are different for children who are intellectually impaired (IQ < 70) compared to non-intellectually impaired children (IQ ≥ 70) ( 8 ).…”

Poincaré Plot Is Useful for Distinguishing Vasovagal Syncope From Postural Tachycardia Syndrome in Children

“…These results suggest that the Poincaré plot may be superior to the frequency-domain indexes of HRV in comparing the autonomic nervous activities between children with VVS and POTS. Moreover, the autonomic functions in children gradually develop and mature with age ( 43 ). This study considered age as a factor and a stratified analysis was implemented to ensure that the results were accurate.…”