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"Reversibility of Cardiovascular Injury With CPAP Use: Mechanisms Involved"

This study has been completed.
Information provided by (Responsible Party):
University of Wisconsin, Madison Identifier:
First received: March 14, 2011
Last updated: September 29, 2015
Last verified: September 2015
The purpose of this study is to determine the factors that are associated with improved cardiovascular function with the use of CPAP therapy on subjects diagnosed with moderate to severe obstructive sleep apnea.

Condition Intervention
Sleep Apnea, Obstructive Hypoxia Hypercapnia Sleep Disorders Obesity Hypertension Coronary Artery Vasospasm Right Ventricular Overload Left Ventricular Function Systolic Dysfunction Ventricular Hypertrophy Other: Clinically prescribed CPAP therapy

Study Type: Interventional
Study Design: Intervention Model: Single Group Assignment
Masking: None (Open Label)
Primary Purpose: Treatment
Official Title: "Reversibility of Cardiovascular Injury With Continuous Positive Airway Pressure (CPAP) Use: Mechanisms Involved"

Further study details as provided by University of Wisconsin, Madison:

Primary Outcome Measures:
  • Changes in endothelium mediated response to brachial artery reactivity test between baseline and 4 and 12 weeks after CPAP therapy [ Time Frame: 14 weeks ]
    Ultrasound based brachial artery reactivity tests will be performed at entry before CPAP therapy and at 4, 12 weeks post CPAP use and 5-7 days after CPAP withdrawal

Secondary Outcome Measures:
  • Changes in arterial stiffness between baseline and after CPAP treatment [ Time Frame: 14 weeks ]
    Subjects will undergo pulse wave velocity testing with applanation tonometry. tonometry recordings will be at entry and after 4 and 12 weeks of CPAP use and 5-7- days after withdrawal.

  • Changes in coronary artery flow under a cold pressor test [ Time Frame: 13 weeks ]
    A subset of subjects with abnormal endothelial function determined during the baseline scan and good echocardiographic images will be invited to participate on this portion of the test. We will record the response to a cold pressor test (submerging their hand in ice water for 1.5 minutes) on left anterior descending coronary artery velocities with transthoracic echocardiography at baseline and after 12 weeks of CPAP therapy.

Enrollment: 90
Study Start Date: March 2011
Study Completion Date: December 2014
Primary Completion Date: September 2014 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Clinically prescribed CPAP therapy
Clinically prescribed CPAP therapy
Other: Clinically prescribed CPAP therapy
CPAP as prescribed by attending physician

Detailed Description:
We will monitor non-invasively changes in arterial stiffness, cardiac mass, pulmonary pressures, endothelial function, etc. We will also assess the reversibility of these changes after only 5-7 days of not using the CPAP mask. In a subgroup of subjects we will explore changes in coronary flow response after 12 weeks of CPAP use compared with baseline.

Ages Eligible for Study:   21 Years to 50 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • subjects naïve of CPAP therapy just recently diagnosed with moderate to severe obstructive sleep apnea (OSA). The degree of OSA is defined by results of a comprehensive polysomnogram requiring an apnea hypopnea index (AHI) >15 events/hour and Epworth score >10, or an AHI >20 events/hour
  • either sex
  • any race
  • between 21-50 years old.

Exclusion Criteria:

  • Systolic blood pressure >160 mmHg, or diastolic blood pressure >100 mmHg
  • Changes in antihypertensive medications in the last 6 weeks
  • Restless leg syndrome
  • Average overnight oxygen saturation below 80%
  • Current use of beta-blockers
  • History of coronary artery disease
  • History of Stroke
  • Atrial fibrillation
  • Peripheral vascular disease
  • Suspected cardiac valve abnormality
  • Ejection fraction <50%
  • Type I and type II Diabetes Mellitus (DM)
  • Asthma or confirmed Chronic Obstructive Pulmonary Disease
  • Cigarette smoking in the last 6 months
  • Raynaud's disease
  • Pregnancy (the normal hormonal changes that occur in pregnancy affect greatly arterial stiffness parameters) If a subject becomes pregnant we will discontinue data collection.
  • Physically incapable of resting on left lateral decubitus for 40 minutes.
  • Mastectomy with lymph node removal that might preclude us to monitor blood pressures on both arms
  Contacts and Locations
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Please refer to this study by its identifier: NCT01317329

United States, Wisconsin
Wisconsin Sleep
Madison, Wisconsin, United States, 53719-1176
Sponsors and Collaborators
University of Wisconsin, Madison
Principal Investigator: Claudia E Korcarz, DVM University of Wisconsin, Madison
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: University of Wisconsin, Madison Identifier: NCT01317329     History of Changes
Other Study ID Numbers: K23HL094760 ( U.S. NIH Grant/Contract )
Study First Received: March 14, 2011
Last Updated: September 29, 2015

Additional relevant MeSH terms:
Sleep Wake Disorders
Sleep Apnea, Obstructive
Coronary Vasospasm
Nervous System Diseases
Neurologic Manifestations
Signs and Symptoms
Mental Disorders
Pathological Conditions, Anatomical
Sleep Apnea Syndromes
Respiration Disorders
Respiratory Tract Diseases
Sleep Disorders, Intrinsic
Signs and Symptoms, Respiratory
Coronary Disease
Myocardial Ischemia
Heart Diseases
Cardiovascular Diseases
Vascular Diseases processed this record on September 21, 2017