Heart Rate Variability and its Modulation Across Lifecycle Among Healthy Individuals.
Introduction: Autonomic imbalance is known to play a key role in health and disease. However, there is a lack of data exploring
the sympathovagal balance across the lifecycle among the healthy Asian Indians
Objective: To compare the changes in HRV (Heart rate variability) indices among clusters of the healthy population across the
life cycle.
Methods: Analysis was performed on pooled data categorised into 4 study groups including fetal (n=90), child (n=90), young
adult (n=134), and old (n=85). ECG was collected and subjected to HRV power spectral analysis.
Results: There was a significant difference in all log-transformed HRV indices between the study groups (p<0.01). Low frequency (LF) and high frequency (HF) HRV indices were lower in the fetal and the older adult group compared to the child and young
adult (p<0.01). Effect size (Cohen’s d) estimates for fetal and young adult groups for LF was 2.9 and that for HF was higher at
3.4. The effect size between young adult and old groups was 1.7 for LF and 2.1 for HF
Conclusion: There was an increment in HRV indices reflecting the maturity of cardiac vagal and cardiac sympathetic control of
the heart from fetal to adult life. The degree of modulation across age groups was greater for the parasympathetic compared to
the sympathetic component.