Very low frequency component of heart rate variability as a marker for therapeutic efficacy in patients with obstructive sleep apnea: Preliminary study

Akiko Noda; Junichiro Hayano; Nami Ito; Seiko Miyata; Fumihiko Yasuma; Yoshinari Yasuda

doi:10.4103/jrms.JRMS_62_18

Very low frequency component of heart rate variability as a marker for therapeutic efficacy in patients with obstructive sleep apnea: Preliminary study

J Res Med Sci. 2019 Sep 30:24:84. doi: 10.4103/jrms.JRMS_62_18. eCollection 2019.

Authors

Akiko Noda^{1

2}, Junichiro Hayano³, Nami Ito⁴, Seiko Miyata⁵, Fumihiko Yasuma⁶, Yoshinari Yasuda⁷

Affiliations

¹ Department of Biomedical Sciences, Chubu University Graduate School of Life and Health Sciences, Kasugai, Japan.
² Innovative Research Center for Preventive Medical Engineering, Nagoya University, Nagoya, Japan.
³ Department of Medical Education, Nagoya City University Graduate School of Medical Sciences, Nagoya, Japan.
⁴ Department of Medical Technology, Nagoya University School of Health Sciences, Nagoya, Japan.
⁵ Department of Psychiatry, Nagoya University Graduate School of Medicine, Nagoya, Japan.
⁶ Department of Internal Medicine, National Hospital Organization Suzuka Hospital, Suzuka, Japan.
⁷ Department of CKD Intitatives, Nagoya University Graduate School of Medicine, Nagoya, Japan.

Abstract

Background: Although positive airway pressure (PAP) therapy is effective for treating obstructive sleep apnea (OSA), some patients with severe OSA are intolerable to this treatment, which may lead to an increase in the mortality and morbidity of cardiovascular diseases. We investigated the relationship between heart rate variability (HRV) and sleep parameters during natural sleep and treatment of patients with OSA.

Materials and methods: This was the cross-sectional observation study. Patients were 17 males with severe OSA who were unable to accept continuous PAP. Standard polysomnography was performed for two consecutive nights, i.e., during natural sleep and following night with bilevel PAP (BiPAP) treatment. Time-dependent responses of the amplitudes of low frequency (LF), very low frequency (VLF), and high frequency components of HRV were assessed with the technique of complex demodulation.

Results: Apnea-hypopnea index, oxygen desaturation time, and percentage of stage 1 sleep were significantly reduced, whereas the percentages of rapid eye movement and stages 3 + 4 sleep were increased, by BiPAP treatment. Therapy also reduced the amplitudes of VLF and LF components of HRV. Difference in amplitudes of VLF during natural sleep and treatment with BiPAP was significantly correlated with difference in percentages of stage 1 and stages 3 + 4 sleep.

Conclusion: Therapy-induced amelioration of OSA and sleep quality was accompanied by decrease in the amplitudes of VLF components of HRV. The VLF component may thus reflect physiological changes in both autonomic activity and sleep structure and serve as an objective marker for therapeutic efficacy in patients with severe OSA.

Keywords: Continuous positive airway pressure; heart rate; obstructive sleep apnea; polysomnography; sleep stage.