Study to Assess the Changes in Blood Clotting Factors and Blood Vessel Wall Function in Obstructive Sleep Apnea
Obstructive sleep apnea is a condition in which people have decreased breathing during their sleep. Untreated sleep apnea has been linked to increased risk for cardiovascular diseases.
This research study is looking at blood clotting factors and blood vessel function in health volunteers and patients with newly diagnosed or untreated obstructive sleep apnea to better understand the underlying mechanisms for increased cardiovascular risk.
Obstructive Sleep Apnea
|Study Design:||Observational Model: Case Control
Time Perspective: Prospective
|Official Title:||Variability of Fibrinolytic Markers and Endothelial Function in Obstructive Sleep Apnea|
- Comparison of Levels of Mean PAI-1 Activity in Patients With Obstructive Sleep Apnea and Controls. [ Time Frame: at the initial visit ] [ Designated as safety issue: No ]
- Comparison of Endothelial (Blood Vessel) Wall Diameter in Patients With Obstructive Sleep Apnea Versus Controls. [ Time Frame: at initial visit ] [ Designated as safety issue: No ]
Biospecimen Retention: Samples With DNA
Blood samples to measure plasminogen activator inhibitor-1 (PAI-1) and tissue plasminogen activator (t-PA)levels, endothelial function,fasting lipid profile and glucose levels.
|Study Start Date:||February 2008|
|Study Completion Date:||April 2012|
|Primary Completion Date:||April 2012 (Final data collection date for primary outcome measure)|
18 years or older with body mass index between 25-45
Obstructive Sleep Apnea Group
Age 18 years or older with body mass index between 25 and 45
Cardiovascular disease (CVD), which includes strokes, has been the number one killer in the United States.Each year about 700,000 people experience a new or recurrent stroke, which translates into about one stroke every 45 seconds. Apart from traditional risk factors for stroke such as hypertension, smoking and atrial fibrillation, obstructive sleep apnea is now being increasingly recognized as another important treatable risk factor.
The majority of strokes and myocardial infarctions are due to atherothrombotic events. Impaired fibrinolytic activity increases the propensity for thromboembolic events. Many different candidate molecules have been studied as the cause of a hypercoagulable state. Plasminogen Activator Inhibitor-1 (PAI-1) is the major physiologic inhibitor of the body's fibrinolytic system including the principal serine protease tissue-type plasminogen activator (t-PA). It is therefore poised to be a pivotal regulator of the fibrinolytic system.Recent studies have shown that PAI-1 levels are elevated in patients with obstructive sleep apnea (OSA) and that PAI-1 levels correlate with severity of OSA.
The purpose of this pilot study is twofold:
- To characterize changes in the blood levels of plasminogen activator inhibitor-1 (PAI-1) and tissue type plasminogen activator ( t-PA) across the 24 hour cycle in patients with obstructive sleep apnea, as compared to normal controls, and to further identify the pattern of changes with varying severity of obstructive sleep apnea, and
- To study endothelial function in patients with obstructive sleep apnea, as compared to normal controls.
Data gathered from this pilot study will be used to initiate a more comprehensive prospective study exploring the link between OSA, endothelial function, the fibrinolytic system and cardiovascular events. This area can be further explored by prospectively following patients to assess for a reduction in such events with treatment of OSA.
|United States, Tennessee|
|Vanderbilt University Medical Center,Department of Neurology|
|Nashville, Tennessee, United States, 37232|
|Principal Investigator:||Kanika Bagai, M.D||Vanderbilt University Medical Center, Nashville, TN|