Mechanisms of Endothelial Cell Dysfunction in Sleep Apnea

Brief Summary

Official Title: “Mechanisms of Endothelial Cell Dysfunction in Sleep Apnea”

Sleep apnea is a common sleep disorder characterized by temporary stops in breathing during sleep and has been associated with the development of cardiovascular disease. This research will investigate one potential mechanism leading to the development of cardiovascular disorder, specifically, the blockage of blood vessels called "vascular occlusion", in subjects with sleep apnea. A group of healthy controls will be used for comparison. All subjects will undergo clinical evaluation followed by an overnight sleep study and a morning blood draw. Subjects with sleep apnea will be treated according to standard clinical management and followed under the research protocol for one month. At the end of one month, a repeat blood draw will be performed on the sleep apnea subjects for comparative analysis. If a control subject is found to have any abnormality during this research study, he or she will be referred for further clinical evaluation.

  • Study Type: Interventional
  • Study Design: Allocation: Non-Randomized, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Basic Science
  • Study Primary Completion Date: October 2013

Detailed Clinical Trial Description

The importance of this project is to investigate mechanisms of vascular disease in sleep apnea and determine pathways for intervention, aiming to prevent the development of cardiovascular disease in these individuals.

This proposed research aims to evaluate both NTPDase activity in lymphocytes and levels of circulating endothelial cells (CECs) in patients with intermittent hypoxemia (IH) due to obstructive sleep apnea (OSA) and healthy controls. This is an original approach to define mechanisms which underlie the high incidence of occlusive vascular events in patients with OSA. The evaluation of such pathophysiological mechanisms will lead to a better understanding of the pathways involved and the development of therapeutic strategies targeting the reduction or avoidance of endothelial injury with the ultimate goal of reducing morbidity and mortality associated with these pathologic events in sleep apnea. The standard of care will be used in this protocol, which involves the use of CPAP (continuous positive airway pressure) for treating sleep apnea.

Interventions Used in this Clinical Trial

  • Device: Continuous Positive Airway Pressure (CPAP)
    • Continuous positive airway pressure (CPAP) is a method of respiratory ventilation which is accepted as the gold standard to treat Obstructive Sleep Apnea (OSA). Subjects found to have OSA after the Nocturnal Polysomnography (NPSG) will be trained in the use of CPAP and will be instructed to use CPAP every night for 30 nights. These subjects will then return for a post-treatment blood draw.

Arms, Groups and Cohorts in this Clinical Trial

  • Active Comparator: Sleep Apnea
    • Subjects found to have Obstructive Sleep Apnea (OSA) with Intermittent Hypoxemia (IH). This arm will undergo a pre-treatment blood draw, one month of Continuous Positive Airway Pressure (CPAP) to treat OSA, and a post-treatment blood draw.
  • No Intervention: Normal Control
    • Subject found to have no evidence of Obstructive Sleep Apnea (OSA) after Nocturnal Polysomnography (NPSG). These subjects will only undergo a blood draw and will not have the Continuous Positive Airway Pressure (CPAP) treatment.

Outcome Measures for this Clinical Trial

Primary Measures

  • NTPDase (vascular enzyme) activity in white blood cells
    • Time Frame: Day 1 (all subjects) and Day 34 (post treatment – sleep apnea only)
      Safety Issue?: No
  • Circulating endothelial cells (CECs)
    • Time Frame: Day 1 (all subjects) and Day 34 (post treatment – sleep apnea only)
      Safety Issue?: No

Secondary Measures

  • Determine the effect of sleep apnea therapy in increasing vascular enzyme (NTPDase) activity and decreasing the level of circulating endothelial cells (CECs).
    • Time Frame: At completion of study
      Safety Issue?: No

Criteria for Participation in this Clinical Trial

Study Group 1: Sleep Apnea

Inclusion Criteria

  • 21 years or older
  • Presence of intermittent hypoxemia (IH) and obstructive sleep apnea (OSA)
  • No diagnosis of hypertension, coronary artery disease, diabetes, stroke, or evidence of underlying vascular disease

Exclusion Criteria

  • Smoking
  • Pregnancy
  • Known cardiovascular disease, stroke, or diabetes
  • Current or previous treatment for sleep apnea
  • Central or Cheyne-Stokes sleep apnea
  • Use of supplemental oxygen at night
  • Alcohol abuse
  • Regular use of sedatives
  • Regular use of aspirin or cholesterol lowering agents

Study Group 2: Normal Controls

Inclusion Criteria

  • 21 years or older
  • No diagnosis of intermittent hypoxemia (IH) or obstructive sleep apnea (OSA)
  • No diagnosis of hypertension, coronary artery disease, diabetes, stroke, or evidence of underlying vascular disease

Exclusion Criteria

  • Smoking
  • Pregnancy
  • Known cardiovascular disease, stroke, or diabetes
  • Use of supplemental oxygen at night
  • Alcohol abuse
  • Regular use of sedatives
  • Regular use of aspirin or cholesterol lowering agents

Gender Eligibility for this Clinical Trial: Both

Minimum Age for this Clinical Trial: 21 Years

Maximum Age for this Clinical Trial: N/A

Are Healthy Volunteers Accepted for this Clinical Trial: Accepts Healthy Volunteers

Clinical Trial Investigator Information

  • Lead Sponsor
    • Weill Medical College of Cornell University
  • Collaborator
    • National Institutes of Health (NIH)
  • Provider of Information About this Clinical Study
    • Ana C. Krieger, MD, Weill Cornell Medical College
  • Overall Official(s)
    • Ana C Krieger, MD, MPH, Principal Investigator, Weill Medical College of Cornell University
  • Overall Contact(s)
    • Allison Maidman, 646-962-9318, alm2041@med.cornell.edu

Source

Clinical Trials content is provided directly by the US National Institutes of Health via ClinicalTrials.gov and is not reviewed separately by ClinicalTrialsFeeds.org. Every page of information about a specific clinical trial contains a unique identifier which can be used to find further details directly from the National Institutes of Health.

The URL of this page is:
http://clinicaltrialsfeeds.org/clinical-trials/show/NCT00859950