Parameters of Overnight Pulse Wave under Treatment in Obstructive Sleep Apnea

Respiration. 2016;92(3):136-43. doi: 10.1159/000448248. Epub 2016 Aug 31.


Background: Sleep-related breathing disorders may promote cardiovascular (CV) diseases. A novel and differentiated approach to overnight photoplethysmographic pulse wave analysis, which includes risk assessment and measurement of various pulse wave characteristics, has been evaluated in obstructive sleep apnea (OSA).

Objectives: The purpose of this study was to assess if and which of the differentiated pulse wave characteristics might be influenced by OSA treatment with positive airway pressure (PAP).

Methods: The study included two protocols. In the case-control study (group A), pulse wave-derived CV risk indices recorded during PAP therapy were compared with those obtained in age, body mass index, and CV risk class-matched patients with untreated OSA (n = 67/67). In the prospective PAP treatment study (group B), 17 unselected patients undergoing a full-night sleep test at baseline and after 23 ± 19 weeks of treatment were analyzed.

Results: In untreated OSA patients (group A), the overnight hypoxic load was increased (SpO2 index 38.7 ± 17.5 vs. 24.0 ± 11.1, p < 0.001) and the pulse wave attenuation index (PWA-I) was lower (29.4 ± 9.2 vs. 33.5 ± 11.8, p = 0.022) than in treated patients. In group B, PAP therapy reduced the hypoxic load and increased the PWA-I significantly. The composite CV risk index was slightly but not significantly reduced.

Conclusions: PAP therapy modified the hypoxic load and pulse wave-derived markers. The PWA-I - associated with sympathetic vascular tone - was most prominently modified by PAP. This novel approach to markers of CV function should be further evaluated in prospective studies.

MeSH terms

  • Aged
  • Cardiovascular Diseases
  • Case-Control Studies
  • Continuous Positive Airway Pressure
  • Cross-Sectional Studies
  • Female
  • Humans
  • Hypoxia / physiopathology*
  • Male
  • Middle Aged
  • Polysomnography
  • Pulse Wave Analysis*
  • Sleep Apnea, Obstructive / physiopathology*
  • Sleep Apnea, Obstructive / therapy
  • Sympathetic Nervous System / physiopathology*