Oxidative Stress and Endothelial Dysfunction in Obstructive Sleep Apnea

Assistance Publique - Hôpitaux de Paris11 enrolled

Overview

Patients with sleep apnea syndrome have repeated apneic events that induce periodic hypoxia-reoxygenation, drawing away an overproduction of oxidants. This exaggerated generation of oxidants is associated with a dysfunction of the vascular endothelium that evolves, in its turn, towards cardiovascular diseases such as systemic hypertension, stroke, and myocardial infarction. The major aim of our study is to examine the effect of CPAP treatment on biochemical (markers of oxidative stress) and functional (endothelium-dependent vascular relaxation reactivity) abnormalities at 1 and 4 weeks of treatment.

Subjects will undergo overnight polysomnography in the sleep laboratory (PSG1, D0), which will be immediately preceded and followed by measurements of oxidative stress in exhaled gas and vascular relaxation. Patients included in the OSAS group will be randomly assigned to treatment by either CPAP or Placebo (sham CPAP) for 4 weeks. Measurements of oxidative stress in exhaled gas and vascular reactivity will be repeated immediately before and after PSG2 and PSG3 at D7 and D30, respectively.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

SINGLE

Enrollment

Conditions

Obstructive Sleep Apnea Syndrome Endothelial Dysfunction

Eligibility

Sex: ALLMin age: 30 YearsMax age: 70 Years

Medical Language ↔ Plain English

Inclusion Criteria: * No smoking * 30-70 years old subjects * being referred for daytime hyper- somnolence and snoring * apnea hypopnea index \>=30/hour and desaturation index\>=30/hour Exclusion Criteria: * Chronic lung diseases. * Exposure to occupational contaminants. * Active smoking within last 2 years. * Alcoholism. * Chronic systemic disease other than OSAS. * Treatment with vasoactive drugs or antioxidants * Respiratory infection or vaccination during the 6 weeks preceding the PSG1.

Outcomes

Primary Outcomes

To examine the effect of CPAP treatment on biochemical (markers of oxidative stress) abnormalities

Time frame: 1 and 4 weeks of treatment

Secondary Outcomes

To compare between patients with severe OSAS and controls, the degree of the production of markers of oxidative stress non-invasively measured in both the exhaled gas and urine samples

Time frame: before and after a nocturnal polysomnography

To compare between patients and controls, the endothelium-dependent vascular relaxation

Time frame: before and after nocturnal polysomnography

To analyze the relationship between these biochemical and functional abnormalities and the standard criteria of severity of OSAS.