Study to Assess the Changes in Blood Clotting Factors and Blood Vessel Wall Function in Obstructive Sleep Apnea

NCT ID: NCT00936481

Last Updated: 2013-10-25

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 34 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2008-02-29
• Study Completion Date: 2012-04-30

Brief Summary

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.

Detailed Description

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.

Conditions

Obstructive Sleep Apnea

Keywords

OSA

Study Design

• Observational Model Type: CASE_CONTROL
• Study Time Perspective: PROSPECTIVE

Study Groups

Healthy controls

18 years or older with body mass index between 25-45

No interventions assigned to this group

Obstructive Sleep Apnea Group

Age 18 years or older with body mass index between 25 and 45

No interventions assigned to this group

Eligibility Criteria

Inclusion Criteria

• Age 18 years or older.
• Subjects are able and willing to provide informed consent.
• Subjects are willing to cooperate with polysomnography and have serial blood draws over a 24-hour period.
• Evidence for OSA (AHI>5 events/hour) without treatment or suspected OSA based on symptoms in the patient group.
• Body mass index of 25-45

Exclusion Criteria

• History of myocardial infarction, stroke or transient ischemic attack (TIA) or peripheral vascular disease.
• History of chronic diseases such as diabetes mellitus, uncontrolled hypertension (SBP >160, DBP > 120), renal failure on dialysis, cancer, autoimmune or liver disease.
• A significant history of medical or psychiatric disease that may impair participation in the trial.
• Evidence of medical instability (cardiac arrhythmias, congestive heart failure, pulmonary disease) that require an expedited evaluation and treatment of the OSA.
• History of alcohol, or drug abuse during the one-year-period prior to trial participation.
• Current use of tobacco products.
• Current treatment with angiotensin converting enzyme-inhibitors and or chronic use of non-steroidal anti-inflammatory agents.
• Another primary sleep disorder that requires intervention with medications or cause disrupted sleep.
• Patients with unusual sleep or wake habits, including shift work.
• Transmeridian travel in the previous 3 months.
• Patients with OSA who have already received treatment with CPAP, surgery or oral appliance.
• Pregnancy; as hormonal changes affect sleep disordered breathing.

• Minimum Eligible Age: 18 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Vanderbilt University

OTHER

Sponsor Role: lead

Responsible Party

Kanika Bagai

Assistant Professor

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Kanika Bagai, M.D

Role: PRINCIPAL_INVESTIGATOR

Vanderbilt University Medical Center, Nashville, TN

Locations

Vanderbilt University Medical Center,Department of Neurology

Nashville, Tennessee, United States

Countries

United States

References

Yaggi HK, Concato J, Kernan WN, Lichtman JH, Brass LM, Mohsenin V. Obstructive sleep apnea as a risk factor for stroke and death. N Engl J Med. 2005 Nov 10;353(19):2034-41. doi: 10.1056/NEJMoa043104.

Reference Type: BACKGROUND

PMID: 16282178 (View on PubMed)

Other Identifiers

090265

Identifier Type: -

Identifier Source: org_study_id