Peripheral Vascular Function in Obstructive Sleep Apnoea

Obesity Clinical Trial

Official title:

Effects of Obstructive Sleep Apnoea and Its Treatment on Macrovascular and Microvascular Function

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01619748
• Other study ID #: STH-16309
• Status: Completed
• Phase: N/A
• First received: June 8, 2012
• Last updated: August 6, 2013
• Start date: June 2012
• Est. completion date: June 2013

Study information

• Verified date: August 2013
• Source: Sheffield Teaching Hospitals NHS Foundation Trust
• Contact: n/a
• Is FDA regulated: No
• Health authority: United Kingdom: National Health Service
• Study type: Observational

Clinical Trial Summary

Peripheral vascular function is impaired in people with obstructive sleep apnoea who are untreated compared with age-, weight- and sex-matched healthy controls.

Description:

Obstructive sleep apnoea (OSA) is a chronic respiratory disorder associated with endothelial dysfunction, increased sympathetic activation and increased cardiovascular risk. The standard treatment paradigm is continuous positive airway pressure (CPAP), however, patient adherence to CPAP is variable. It is unclear to what extent that poor adherence to CPAP therapy augments vascular endothelial function and reduces cardiovascular risk compared to excellent adherence. The main aim of this research is to investigate vascular endothelial function in OSA patients who are poorly-adherent to CPAP therapy. Nitric oxide (NO)-mediated, endothelium-dependent macrovascular and microvascular function (by brachial artery flow-mediated dilatation and forearm cutaneous thermal hyperaemia, respectively) and generalised microvascular function (by post-occlusion reactive hyperaemia) will be assessed in three obese OSA patient populations (high-adherence (n=20); low adherence (n=20); and, untreated (n=20)) and age-/BMI-matched OSA-free controls. We will also assess body composition, cardiovascular risk, lipid status and functional capacity. This research will evaluate treatment efficacy in patients who are poorly-adherent to CPAP treatment and could identify whether an alternative approach to their care should be explored.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 45
• Est. completion date: June 2013
• Est. primary completion date: April 2013
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 18 Years to 90 Years

Eligibility

Inclusion Criteria:

• Obstructive sleep apnoea diagnosed using overnight polysomnography

• Age 18-90 years

Exclusion Criteria:

• Unable to perform the tests involved in the study

• Unable to provide written informed consent

Study Design

Observational Model: Case Control, Time Perspective: Cross-Sectional

Related Conditions & MeSH terms

• Apnea
• Obesity
• Obstructive Sleep Apnoea
• Sleep Apnea Syndromes
• Sleep Apnea, Obstructive

Locations

Country	Name	City	State
United Kingdom	Centre for Sport and Exercise Science, Sheffield Hallam University	Sheffield	South Yorkshire
United Kingdom	Sheffield Teaching Hospitals NHS FT	Sheffield	South Yorkshire

Sponsors (2)

Lead Sponsor	Collaborator
Sheffield Teaching Hospitals NHS Foundation Trust	Sheffield Hallam University

Country where clinical trial is conducted

United Kingdom, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Flow-mediated dilatation of the brachial artery	The brachial artery dilator response to a 5-min period of forearm arterial occlusion will be measured using a vascular ultrasound scanner and a 7-MHz linear array probe.	Baseline only	No
Secondary	GTN-mediated dilatation of the brachial artery	The brachial artery vasodilator response to a 400 microgram sublingual dose of glyceryl trinitrate will be measured using vascular ultrasound imaging.	Baseline only	Yes
Secondary	Forearm skin blood flow response to 5-min proximal-cuff arterial occlusion	Proximal arterial occlusion will be performed by inflating a blood pressure cuff placed on the upper arm to 200 mmHg for 5 min. After cuff deflation, the skin blood flow response will be measured using laser Doppler flowmetry.	Baseline only	No
Secondary	Forearm skin blood flow response to localised heating at 42 degrees C	A local heating unit on the forearm will be heated from 33 to 42 degrees C at a rate of 1 degree C every 10 s. Temperature will be held at 42 degrees C for 35 min. The increase in skin blood flow will be measured using a laser Doppler flowmetry probe placed in the centre of the local heating unit.	Baseline only	No