The Effects of Continuous Positive Airway Pressure (CPAP) on Sympathetic Activity in Different Sites of Activation

Exercise Test Clinical Trial

Official title:

The Effects of Continuous Positive Airway Pressure (CPAP) on Sympathetic Activity in Different Sites of Activation

Clinical Trial Details — Status: Active, not recruiting

Administrative data

• NCT number: NCT01336335
• Other study ID #: Sympathetic activity and OSA
• Status: Active, not recruiting
• Phase: Phase 3
• First received: April 13, 2011
• Last updated: April 13, 2011
• Start date: July 2010
• Est. completion date: July 2011

Study information

• Verified date: July 2010
• Source: University of Sao Paulo
• Contact: n/a
• Is FDA regulated: No
• Health authority: Brazil: Ministry of Health
• Study type: Interventional

Clinical Trial Summary

Recent evidences suggest that obstructive sleep apnea (OSA) can contribute to cardiovascular disease even in the absence of hypertension. However, there are few data regarding the impact of OSA on the sympathetic system in apparently normotensive patients with OSA as well as the impact of treatment with continuous positive airway pressure in different sites of activation (heart, peripheral nerves and circulating catecholamines)

Recruitment information / eligibility

• Status: Active, not recruiting
• Enrollment: 20
• Est. completion date: July 2011
• Est. primary completion date: July 2011
• Accepts healthy volunteers: No
• Gender: Male
• Age group: 30 Years to 60 Years

Eligibility

Inclusion Criteria:

• Severe OSA males

Exclusion Criteria:

• Smoking

• Sustained Hypertension

• Heart failure

• Diabetes

• Renal diseases

• Under use of any medication

• Under treatment for OSA

Study Design

Allocation: Randomized, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Treatment

Related Conditions & MeSH terms

• Blood Pressure Monitoring, Ambulatory
• Catecholamines
• Exercise Test
• Radionuclide Imaging (MIBG Scintigraphy)
• Sympathetic Nerve Activity

Intervention

Device:
• CPAP
CPAP

Locations

Country	Name	City	State
Brazil	Heart Institute	São Paulo

Sponsors (1)

Lead Sponsor	Collaborator
University of Sao Paulo

Country where clinical trial is conducted

Brazil, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	improvement in sympathetic activity in muscle sympathetic nerve activity (MSNA)	Improvement in MSNA will be quantified as burst frequency over time (bursts per minute) and as burst frequency corrected for heart rate values (bursts per 100 heartbeats)in the begining and after 3 months.	3 months	No
Secondary	improvement in sympathetic activity evaluated in different sites of activation	All measurement will be performed at the begining and after 3 months. Blood: blood and 24 hour urine will be collected for norepinephrine quantification.; Heart: Early (15 min) and delayed (3 hr) planar images will be taken after injection of (123)I-MIBG. The mean counts of the whole heart and the mediastinum will be obtained to calculate heart-to-mediastinum count ratios from the early images (H/Me) and from the delayed images (H/Md) and the myocardial washout rate (WR).; Blood pressure: 24 hour ambulatory blood pressure monitoring and blood pressure during exercise test (treadmill test)	3 months	No