C-reactive protein and heart rate recovery in middle-aged men with severe obstructive sleep apnea

Sleep Breath. 2012 Sep;16(3):629-37. doi: 10.1007/s11325-011-0549-2. Epub 2011 Jun 27.

Abstract

Objective: The study aimed to evaluate whether the inflammatory marker "high-sensitivity C-reactive protein (hsCRP)" level was associated with impaired heart rate recovery at 1 min after exercise termination (HRR-1) in middle-aged patients with severe obstructive sleep apnea (OSA).

Methods: Thirty middle-aged male patients (40-64 years old) with severe OSA (apnea-hypopnea index [AHI] ≥ 30 h(-1)) and 30 subjects without OSA (AHI < 5 h(-1)), matched with age and body mass index (BMI), were recruited. All subjects underwent an overnight polysomnography and completed a symptom-limited maximal exercise test. Cardiopulmonary parameters included peak oxygen consumption (VO(2peak)) and heart rate response during and immediately after exercise. Fasting blood samples were drawn for hsCRP analysis.

Result: Patients with severe OSA had significantly higher hsCRP levels (0.18 vs. 0.07 mg/dl, P < 0.01), lower reduced HRR-1, peak heart rate, and VO(2peak) values than those in the controls. The hsCRP levels significantly correlated with HRR-1 in the OSA group (r = -0.69, P < 0.01) after adjustment for VO(2peak) (r = -0.66, P < 0.01). Furthermore, stepwise multiple regression analysis showed that HRR-1 and AHI were significant predictors of hsCRP levels in all participants (adjusted R(2) = 0.53, P < 0.01).

Conclusions: Blunted HRR was shown in middle-aged men with severe OSA, and it was associated with high hsCRP levels significantly.

Trial registration: ClinicalTrials.gov NCT00813852.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Arousal / physiology
  • C-Reactive Protein / metabolism*
  • Exercise Test*
  • Heart Rate / physiology*
  • Humans
  • Inflammation Mediators / blood*
  • Male
  • Middle Aged
  • Polysomnography
  • Reference Values
  • Sleep Apnea, Obstructive / diagnosis
  • Sleep Apnea, Obstructive / physiopathology*
  • Statistics as Topic
  • Sympathetic Nervous System / physiopathology

Substances

  • Inflammation Mediators
  • C-Reactive Protein

Associated data

  • ClinicalTrials.gov/NCT00813852