HRV & Aging

Methods

Cross-sectional analysis of HRV data from 296,000+ participants

Key Findings

• Steepest HRV decline occurs between ages 20-40
• Men have higher RMSSD than women until approximately age 50
• Decline rate slows after age 50 in both sexes
• HRV coefficient of variation increases with age in males after 40

Limitations

Cross-sectional design cannot establish individual trajectories

Methods

Review of long-term studies on HRV and health outcomes

Key Findings

• 24-hour SDNN < 50ms associated with higher mortality
• Low HRV predicts cardiovascular events independently of other risk factors
• Association holds across age groups
• Short-term RMSSD also predictive but less studied for mortality

Limitations

Most studies in populations with existing heart disease

Methods

Prospective study of 501 twins with 24-hour Holter ECG monitoring

Key Findings

• HRV predicted mortality independent of genetic factors
• Deceleration capacity showed strongest mortality association
• Effect persisted after controlling for traditional CVD risk factors
• Suggests HRV reflects brain-heart-autonomic network health

Limitations

All-male veteran population