Inflammatory Mediators in Obstructive Sleep Apnoea Syndrome; Mechanisms of Production and the Effect of Long Term Antioxidants Administration
Recruitment status was: Recruiting
Obstructive Sleep Apnea Syndrome (OSAS) is associated with elevated plasma levels of IL-6 and TNF-α, which cannot be accounted for by obesity (Vgontzas et al Sleep Med Rev 2005;9:211-24, Ciftci et al Cytokine 2004;28:87-91].
Obstructive apneas-hypopneas are accompanied by strenuous diaphragmatic contractions before the ensuing arousals and re-establishment of airway patency. We have shown that strenuous diaphragmatic contractions induced by resistive loading lead to elevated plasma levels of IL-6, TNF-α, and IL-1β (Vassi-lakopoulos et al AJRCCM 2002;166:1572-8) with concomitant up-regulation of the cytokines within the diaphragmatic myofibers (Vassilakopoulos et al AJRCCM 2004;170:154-61).
OSAS patients exhibit frequent episodes of hypoxemia during the night. Loaded breathing is a form exercise for the respiratory muscles, and both acute and chronic hypoxia lead to an augmented plasma IL-6 response to exercise compared to normoxia (Lundby et al Eur J Appl Physiol 2004;91:88-93).
In OSAS, monocytes have oxidative stress (Dyugovskaya et al AJRCCM 2002;165:934-9) and produce more cytokines (TNF-α) in vitro (Minoguchi et al Chest 204;126:1473-9).
Hypothesis #1: plasma levels of IL-6 and TNF-α are increased during the night in OSAS patients secondary to the intermittent strenuous diaphragmatic contractions and the episodes of hypoxia-reoxygenation associated with the obstructive apneas-hypopneas.
Hypothesis #2: monocytes from sleep apnea patients, exhibit augmented intracellular expression of IL-6 and TNF-α during the night.
Hypothesis #3: Oxidative stress is a stimulus for cytokine upregulation in OSAS.
Obstructive Sleep Apnea Syndrome
Device: Oxygen supplementation
Drug: Vitamin A, Vitamin C, Vitamin E, Allopurinol, N-Acetylcysteine
|Study Design:||Allocation: Non-Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Factorial Assignment
Masking: Open Label
Primary Purpose: Basic Science
|Official Title:||Inflammatory Mediators in Obstructive Sleep Apnoea Syndrome; Mechanisms of Production and the Effect of Long Term Antioxidants Administration|
- IL-6 Area under the curve [ Time Frame: three months ] [ Designated as safety issue: No ]The primary outcome measure ( IL-6 Area under the curve) is evaluated at the end of each polysonographic study. We anticipate each subject to have completed all three sudies within one month and receive the antioxidant supplementation for an additional 60 day period. In total three months
- TNF-a area under the curve [ Time Frame: three months ] [ Designated as safety issue: No ]The secondary outcome measure ( TNF-a Area under the curve) is evaluated at the end of each polysonographic study. we anticipate each subject to have completed all three sudies within one month and receive the antioxidant supplementation for an additional 60 day period. In total three months
|Study Start Date:||August 2010|
|Estimated Study Completion Date:||October 2010|
|Estimated Primary Completion Date:||October 2010 (Final data collection date for primary outcome measure)|
Experimental: OSAS patients
This arm includes the OSAS diagnosed cohort that has been planned to undergo four polysomnographic studies. One standard, one with oxygen supplementation, one with n-CPAP device and one post antioxidants administration
administration of continuous positive airway pressure through a nasal deviceDevice: Oxygen supplementation
Oxygen supplementation (3L) through nasal spectaclesDrug: Vitamin A, Vitamin C, Vitamin E, Allopurinol, N-Acetylcysteine
Vitamin A 50,000 IU, Vitamin C 1000 mg , Vitamin E 200 mg, Allopurinol 600 mg, N-Acetylcysteine 2 g. Duration is set for 60 days
No Intervention: Control Group
This group is scheduled to undergo a plain polysomnographic study, whilst plasma cytokine levels will be measured. It will comprise of healthy, non-OSAS volunteers.
Please refer to this study by its ClinicalTrials.gov identifier: NCT01188005
|Department of Critical Care Evangelismos General Hospital|
|Athens, Attiki, Greece|
|Principal Investigator:||Theodoros Vassilakopoulos, MD, PhD||Associate Professor in Critical Care, University of Athens|