Associations between Sleep Quality and Heart Rate Variability: Implications for a Biological Model of Stress...

Area of Science:

• Autonomic Nervous System Physiology
• Sleep Science
• Cardiovascular Regulation

Background:

• The autonomic nervous system regulates vital functions, including sleep-wake cycles.
• While autonomic dysfunction and sleep are studied, links between short-term sleep health and autonomic function in healthy individuals are less explored.
• The Pittsburgh Quality of Sleep Index (PSQI) assesses subjective sleep quality, latency, duration, efficiency, disturbances, medication use, and daytime dysfunction.

Purpose of the Study:

• To investigate the relationship between short-term sleep quality and duration and heart rate variability (HRV) in healthy individuals.
• To understand the impact of stress and sleep on HRV indices for integration into wearable device biological models.

Main Methods:

• A cross-sectional study involving 60 healthy participants.
• Sleep parameters were collected at study commencement.
• Heart rate variability (HRV) was measured using electrocardiogram (ECG) during resting and stress (Trier Stress Test) conditions.

Main Results:

• The low-frequency to high-frequency (LF:HF) ratio increased significantly during the stress task compared to rest.
• Very-low-frequency and high-frequency HRV showed an inverse relationship with impaired sleep during stress.
• Very-low-frequency HRV during stress was inversely correlated with poor sleep quality, daytime dysfunction, and global sleep score.

Conclusions:

• Wearable technology data, particularly HRV, requires consideration of sleep states for accurate interpretation.
• Autonomic functioning, specifically very-low-frequency HRV during stress, reflects negative sleep indices.
• Findings offer insights into stress, sleep, and autonomic regulation for biological models in wearable health tech.