Increased nocturnal arterial pulsation frequencies of obstructive sleep apnoea patients is associated with an increased number of lapses in a psychomotor vigilance task

Samu Kainulainen; Brett Duce; Henri Korkalainen; Akseli Leino; Riku Huttunen; Laura Kalevo; Erna S Arnardottir; Antti Kulkas; Sami Myllymaa; Juha Töyräs; Timo Leppänen

doi:10.1183/23120541.00277-2020

Increased nocturnal arterial pulsation frequencies of obstructive sleep apnoea patients is associated with an increased number of lapses in a psychomotor vigilance task

ERJ Open Res. 2020 Nov 16;6(4):00277-2020. doi: 10.1183/23120541.00277-2020. eCollection 2020 Oct.

Authors

Samu Kainulainen^{1

2}, Brett Duce^{3

4}, Henri Korkalainen^{1

2}, Akseli Leino^{1

2}, Riku Huttunen¹, Laura Kalevo^{1

2}, Erna S Arnardottir^{5

6}, Antti Kulkas^{1

7}, Sami Myllymaa^{1

2}, Juha Töyräs^{1

2

8}, Timo Leppänen^{1

2}

Affiliations

¹ Dept of Applied Physics, University of Eastern Finland, Kuopio, Finland.
² Diagnostic Imaging Center, Kuopio University Hospital, Kuopio, Finland.
³ Sleep Disorders Centre, Dept of Respiratory and Sleep Medicine, Princess Alexandra Hospital, Brisbane, Australia.
⁴ Institute for Health and Biomedical Innovation, Queensland University of Technology, Brisbane, Australia.
⁵ Dept of Computer Science, Reykjavik University, Reykjavik, Iceland.
⁶ Internal Medicine Services, Landspitali - The National University Hospital of Iceland, Reykjavik, Iceland.
⁷ Dept of Clinical Neurophysiology, Seinäjoki Central Hospital, Seinäjoki, Finland.
⁸ School of Information Technology and Electrical Engineering, The University of Queensland, Brisbane, Australia.

Abstract

Objectives: Besides hypoxaemia severity, heart rate variability has been linked to cognitive decline in obstructive sleep apnoea (OSA) patients. Thus, our aim was to examine whether the frequency domain features of a nocturnal photoplethysmogram (PPG) can be linked to poor performance in the psychomotor vigilance task (PVT).

Methods: PPG signals from 567 suspected OSA patients, extracted from Type 1 diagnostic polysomnography, and corresponding results of PVT were retrospectively examined. The frequency content of complete PPGs was determined, and analyses were conducted separately for men (n=327) and women (n=240). Patients were grouped into PVT performance quartiles based on the number of lapses (reaction times ≥500 ms) and within-test variation in reaction times. The best-performing (Q1) and worst-performing (Q4) quartiles were compared due the lack of clinical thresholds in PVT.

Results: We found that the increase in arterial pulsation frequency (APF) in both men and women was associated with a higher number of lapses. Higher APF was also associated with higher within-test variation in men, but not in women. Median APF (β=0.27, p=0.01), time spent under 90% saturation (β=0.05, p<0.01), female sex (β=1.29, p<0.01), older age (β=0.03, p<0.01) and subjective sleepiness (β=0.07, p<0.01) were significant predictors of belonging to Q4 based on lapses. Only female sex (β=0.75, p<0.01) and depression (β=0.91, p<0.02) were significant predictors of belonging to Q4 based on the within-test variation.

Conclusions: In conclusion, increased APF in PPG provides a possible polysomnography indicator for deteriorated vigilance especially in male OSA patients. This finding highlights the connection between cardiorespiratory regulation, vigilance and OSA. However, our results indicate substantial sex-dependent differences that warrant further prospective studies.