Introduction

Many physiological functions change with age and differ based on sex. Women report less sleep quality while having better polysomnography (PSG) defined sleep quality than men. This analysis evaluates changes in objective non-electroencephalogram (EEG) sleep quality across the adult human life span based on cardiopulmonary coupling (CPC) calculated sleep quality index (SQI).

Methods

We conducted an analysis of de-identified data from the SleepImage® System¹, using methods based on coupling and coherence of heart rate variability and respiratory tidal volume variability, to derive sleep stages presented in the CPC spectrogram and calculate the SQI. Included in the analysis are one million nights of sleep recording from individuals ≥18 years old (45.5% women/54.5% men, average of 2 nights) with ≥6 hours of sleep duration, ≥4 hours of total sleep time, and good signal quality (≥80%).

Results

Age groups were defined as:

• 18-30 years (46.0% women/54.0% men)
• 31-40 years (41.6% women/58.4% men)
• 41-50 years (42.7% women/57.3% men)
• 51-60 years (46.8% women/53.2% men)
• 61-70 years (48.8% women/51.2% men)
• ≥71 years (47.1% women/52.9% men)

On average, women have significantly higher SQI than men in all age groups; SQI gradually declines in both sexes until around 71 years of age, when the decline stabilizes. Average sleep efficiency is significantly lower in women in all age groups and starts to decline in both sexes at ≥51 years of age. AHI_3% is significantly lower in women compared to men in all age groups. AHI_3% gradually increases with age, most prominently in men between 31-51 years of age and women between 41-51 years of age. A stronger correlation of AHI_3% with SQI is observed in men that declines at ≥61 years of age.

Conclusion

In adults, SQI declines and AHI_3% increases with increasing age. CPC-SQI is higher in women than men in all age groups, mirroring what is reported from PSG studies.

[1] Product offered by MyCardio LLC, Denver, CO, USA.