Heart Rate Variability Analysis in Obstructive Sleep Apnoea Patients with Daytime Sleepiness

Seren Ucak; Hasthi U Dissanayake; Philip de Chazal; Yu Sun Bin; Kate Sutherland; Bianca Setionago; Benjamin Tong; Brendon J Yee; Kristina Kairaitis; John R Wheatley; Amanda J Piper; Peter A Cistulli; Sydney Sleep Biobank Investigators

doi:10.1093/sleep/zsae075

Heart Rate Variability Analysis in Obstructive Sleep Apnoea Patients with Daytime Sleepiness

Sleep. 2024 Mar 26:zsae075. doi: 10.1093/sleep/zsae075. Online ahead of print.

Authors

Seren Ucak¹, Hasthi U Dissanayake^{1

2}, Philip de Chazal^{1

3}, Yu Sun Bin^{1

2}, Kate Sutherland^{1

2}, Bianca Setionago¹, Benjamin Tong^{1

2}, Brendon J Yee^{4

5}, Kristina Kairaitis^{4

6

7}, John R Wheatley^{4

6

7}, Amanda J Piper^{4

8}, Peter A Cistulli^{1

2}; Sydney Sleep Biobank Investigators

Affiliations

¹ Charles Perkins Centre and Northern Clinical School, Faculty of Medicine and Health, University of Sydney, Sydney, Australia.
² Department of Respiratory and Sleep Medicine, Royal North Shore Hospital, Sydney, Australia.
³ School of Biomedical Engineering, Faculty of Engineering, University of Sydney, Sydney, Australia.
⁴ Sydney Medical School, Faculty of Medicine and Health, University of Sydney, Sydney, Australia.
⁵ Woolcock Institute of Medical Research, Royal Prince Alfred Hospital, Sydney, Australia.
⁶ Ludwig Engel Centre for Respiratory Research, Westmead Institute for Medical Research, Sydney, Australia.
⁷ Department of Respiratory and Sleep Medicine, Westmead Hospital, Sydney, Australia.
⁸ Department of Respiratory and Sleep Medicine, Royal Prince Alfred Hospital, Sydney, Australia.

PMID: 38531670
DOI: 10.1093/sleep/zsae075

Abstract

Study objectives: Recent studies suggest sleepy patients with OSA are at higher risk for incident cardiovascular disease. This study assessed cardiac autonomic function in sleepy versus non-sleepy patients with obstructive sleep apnoea (OSA) using heart rate variability (HRV) analysis. We hypothesised that HRV profiles of sleepy patients would indicate higher cardiovascular risk.

Methods: Electrocardiograms (ECG) derived from polysomnograms (PSG) collected by the Sydney Sleep Biobank were used to study HRV in groups of sleepy (ESS≥10) and non-sleepy OSA patients (ESS<10). HRV parameters were averaged across available ECG signal during N2 sleep.

Results: A total of 421 patients were evaluated, with mean age of 54 (14) years, body mass index (BMI) of 33 (9) kg/m2, apnoea hypopnoea index (AHI) of 21 (28) events/h and, 66% male. The sleepy group consisted of 119 patients, and the non-sleepy group 302 patients. Sleepy patients exhibited lower HRV values for: root mean square successive difference (RMSSD, p= 0.028); total power (TP, p= 0.031); absolute low frequency (LF, p= 0.045); and high frequency (HF, p= 0.010) power compared to Non-Sleepy patients. Sleepy patients with moderate to severe OSA exhibited lower HRV values for: (RMSSD, p= 0.045; TP, p= 0.052) ; absolute LF (p= 0.051); and HF power (p= 0.025). There were no differences in other time and frequency domain HRV markers.

Conclusions: This study shows a trend towards parasympathetic withdrawal in sleepy OSA patients, particularly in moderate to severe cases, lending mechanistic support to the link between the sleepy phenotype and CVD risk in OSA.

Keywords: Heart rate variability; autonomic nervous system; cardiovascular risk; excessive daytime sleepiness; obstructive sleep apnoea.