Clinical trial NCT01027078: Mechanism of Endothelial Dysfunction in Obstructive Sleep Apnea (OSA)
Official title: Mechanism of Endothelial Dysfunction in Obstructive Sleep Apnea
Study type: OBSERVATIONAL
Overall status: TERMINATED
Conditions: Obstructive Sleep Apnea
Lead sponsor: Ohio State University
Sponsor class: OTHER
First posted: 2009-12-07
Enrollment: 90
Sex: ALL
Minimum age (years): 18
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: COHORT
Time perspective: PROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Participants: will be 36 patients with newly diagnosed OSA and 36 age and BMI matched controls.

Patients with OSA will be enrolled from the sleep disorders center at OSU among patients who underwent a recent (past 4 weeks) polysomnography that is positive for OSA, and never were treated with CPAP.

Inclusion criteria will be AHI \> 15 events per hours.

Brief summary: The investigators hypothesized that patients with Obstructive Sleep Apnea (OSA) who are free of any cardiovascular disease will have early microcirculatory changes that are unique to OSA, and therefore would resolve with treatment of OSA.

Detailed description: Impaired vascular regulation of the microcirculation is a consequence of Obstructive Sleep Apnea (OSA). Nitric Oxide (NO) related endothelial dysfunction occurs in OSA as the earliest vascular abnormality prior to the manifestation of vascular disease and it results in impaired vasodilatory response to hypoxia. These abnormalities have already been described in OSA patients. The role of oxidative stress in endothelial dysfunction is present in vascular disorders. The presence of oxidative stress in OSA patients is also well established. The effect of increased superoxide on endothelial function has also been described in the literature. The mechanism of this effect is unknown and is the focus of this research.

We hypothesized that patients with Obstructive Sleep Apnea (OSA) who are free of any cardiovascular disease will have early microcirculatory changes that are unique to OSA, and therefore would resolve with treatment of OSA.

Eligibility criteria: Inclusion criteria:

1. Apnea-Hypopnea Index (AHI) \> 15 events per hours.

Exclusion criteria:

1. Hypertension defined by existing treatment with antihypertensives or any measurement of systolic pressure above 130 mmHg, or diastolic pressure above 85 mmHg;
2. Dyslipidemia defined by fasting cholesterol above 200; or fasting LDL over 150 mg/dl;
3. Diabetes defined as existing diagnosis, hemoglobin A1C \>7 or fasting glucose \>110 on two separate measurements (standard fasting glucose or HbA1C criteria);
4. CAD defined by history of angina, coronary event or abnormal stress test;
5. Peripheral Vascular Disease (PVD) defined by history of stroke, claudication or abnormal Ankle brachial index;
6. Concurrent smoking;
7. Pregnancy;
8. Use of erectile dysfunction drugs, or any medications for chronic conditions; 9)Chronic liver or renal disease. Fasting blood test for glucose, cholesterol, on all participants who have not had these tests in the 6 month prior to enrollment, will be obtained at the time of screening. The remaining criteria will be evaluated by reviewing the medical records and history taking on the day of first visit.

Primary outcomes:
measure: eNOS Expression
timeFrame: Measured at basline and 3-months post-treatment (CPAP) initiation
Secondary outcomes:
measure: Peroxynitrite Formation
timeFrame: Measured at basline and 3-months post-treatment (CPAP) initiation
Other outcomes:
measure: Superoxide Production
timeFrame: Measured at basline and 3-months post-treatment (CPAP) initiation
measure: Plasma BH2 and BH4 Levels
timeFrame: Measured at basline and 3-months post-treatment (CPAP) initiation
measure: Plasma ADMA Levels
timeFrame: Measured at basline and 3-months post-treatment (CPAP) initiation
Locations:
city: Columbus
country: United States
facility: The Davis Heart and Lung Research Institute
state: Ohio
Study officials:
affiliation: Ohio State University
name: Rami Khayat, MD
role: PRINCIPAL_INVESTIGATOR
References: