Overnight pulse wave analysis to assess autonomic changes during sleep in insomnia patients and healthy sleepers

PLoS One. 2020 May 7;15(5):e0232589. doi: 10.1371/journal.pone.0232589. eCollection 2020.

Abstract

Insomnia has been associated with increased cardiovascular (CV) risk, which may be linked to sympathetic activation. Non-invasive overnight pulse wave analysis may be a useful tool to detect early signs of autonomic changes during sleep in insomniacs. Fifty-two participants (26 men, 37±13 years, BMI: 24±5 kg/m2, 26 insomniacs/ 26 controls) underwent overnight polysomnography with pulse oximetry and pulse wave analysis including pulse rate, vascular stiffness (pulse propagation time, PPT), and a composite cardiac risk index based on autonomic function and overnight hypoxia. We identified two subgroups of insomniacs, with and without objectively disturbed sleep (sleep efficiency SE≤80%, n = 14 vs. SE>80%, n = 12), and observed increased pulse rate and vascular stiffness in insomnia cases when diagnosis was based on both, subjective and objective criteria. Both insomnia groups were associated with higher overnight pulse rate than controls (median/ IQR: low-SE (low sleep efficiency): 67/ 58-70bpm; high-SE: 66/ 63-69bpm; controls: 58/ 52-63bpm; p = 0.01). Vascular stiffness was higher (reduction of PPT) in low-SE insomniacs compared with high-SE insomniacs and controls (169/ 147-232ms; 237/ 215-254ms; 244/ 180-284ms; p = 0.01). The cardiac risk index was increased in low-SE insomniacs (0.2/ 0.0-0.7; 0.0/ 0.0-0.4; 0.0/ 0.0-0.3; p = 0.05). Our results suggest a hyperarousal state in young and otherwise healthy insomniacs during sleep. The increased pulse rate and vascular stiffness in insomniacs with low SE suggest early signs of rigid vessels and potentially, an elevated CV risk. Overnight pulse wave analysis may be feasible for CV risk assessment in insomniacs and may provide a useful tool for phenotyping insomnia in order to provide individualized therapy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Cardiovascular System / pathology*
  • Female
  • Heart Rate*
  • Humans
  • Male
  • Middle Aged
  • Pulse Wave Analysis / methods*
  • Sleep Initiation and Maintenance Disorders / pathology*
  • Young Adult

Grants and funding

The study was funded by the Qatar National Research Fund – National Priorities Research Program (NPRP # 5-1327-2-568), the Charité – Universitätsmedizin Berlin owned funding, the Swedish Heart and Lung Foundation (grant 20120811, 20160584), the Russian Federation RF Government (# 075-15-2019-1885), and the agreement concerning research and education of doctors at the Sahlgrenska University Hospital (LUA ALF ALFGBG-534591 and 725601). The funder ASR (Advanced Sleep Research GmbH) provided support in the form of salary for author KL. The funders had no role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the ‘author contributions’ section.