title: Reduced cardiac sympathetic autonomic tone after long-term nasal continuous positive airway pressure in obstructive sleep apnoea syndrome.
abstract: The increased sympathetic activation that occurs in obstructive sleep apnoea (OSA) may play an important role in associated morbidity. We investigated the effect of long-term (3 month) nasal continuous positive airway pressure (CPAP) on the autonomic nervous system assessed by heart rate variability (HRV). Fourteen patients (12 men), mean age 61.4 +/- 8.1 years, with OSA underwent continuous synchronized electrocardiographic and polysomnographic monitoring. The apnoea/hypopnoea index (AHI) decreased from 50.6 +/- 13.7 to 2.2 +/- 2.5 events h-1 after CPAP. HRV analysis showed significant decreases in low frequency (LF; from 7.12 +/- 1.06 to 6.22 +/- 1.18 ln ms2 Hz-1; P < 0.001), high frequency (HF; from 5.91 +/- 0.87 to 5.62 +/- 0.92 ln ms2 Hz-1; P < 0.05) and LF/HF (from 1.21 +/- 0.12 to 1.11 +/- 0.15 ln ms2 Hz-1; P < 0.001) when the patients were asleep. The decrease in LF/HF was prolonged into the daytime (from 1.33 +/- 0.22 to 1.24 +/- 0.21 ln ms2 Hz-1; P < 0.001). Treatment of OSA by CPAP significantly reduced the parameters of cardiac sympathetic tone, a favourable effect.
authors: Laboratoire de Physiologie GIP-Exercice, Service d'Exploration Fonctionnelle CardioRespiratoire, Université Jean Monnet, Saint-Etienne, France.
authors: F
authors: F
authors: Roche
authors: I
authors: I
authors: Court-Fortune
authors: V
authors: V
authors: Pichot
authors: D
authors: D
authors: Duverney
authors: F
authors: F
authors: Costes
authors: A
authors: A
authors: Emonot
authors: J M
authors: JM
authors: Vergnon
authors: A
authors: A
authors: Geyssant
authors: J R
authors: JR
authors: Lacour
authors: J C
authors: JC
authors: Barthélémy
mesh_terms: D000328:Adult; D000368:Aged; D004562:Electrocardiography; D005260:Female; D006321:Heart / Q000294:innervation / Q000503:physiopathology*; D006339:Heart Rate / Q000502:physiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D017286:Polysomnography; D011175:Positive-Pressure Respiration / Q000009:adverse effects*; D012891:Sleep Apnea Syndromes / Q000150:complications / Q000503:physiopathology* / Q000628:therapy; D013564:Sympathetic Nervous System / Q000503:physiopathology*