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[Time-sequential changes of vagal activity with aging]
T Sakurabayashi1, T Sawanobori, H Ishii
1Second Department of Medicine, Yamanashi Medical College.
Journal of Cardiology
|January 1, 1993
Summary
Cardiac vagal activity, measured by RR50, shows a significant circadian rhythm that diminishes with age. This decline in vagal tone with aging impacts heart rate regulation.
Area of Science:
- Cardiology
- Chronobiology
- Autonomic Nervous System Physiology
Context:
- Cardiac autonomic function, specifically vagal activity, exhibits daily rhythms.
- Aging is known to influence physiological processes, including cardiovascular regulation.
Purpose:
- To investigate the circadian rhythm of cardiac vagal activity using RR50 measurements.
- To determine how aging affects the circadian parameters of vagal activity and heart rate.
Summary:
- Circadian rhythms of RR interval and RR50 were analyzed in 154 healthy volunteers (ages 12-83).
- While RR interval amplitude decreased with age, RR50 showed significant age-related declines in MESOR and amplitude, with acrophase delay.
- These findings validate the circadian rhythm of cardiac vagal activity and demonstrate its reduction with aging.
Impact:
- Provides evidence for age-related decline in cardiac vagal tone.
- Highlights the importance of considering circadian rhythms in cardiovascular health and aging.
- Suggests that reduced vagal activity with aging contributes to altered heart rate regulation.
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