Clinical trial NCT01619748: Peripheral Vascular Function in Obstructive Sleep Apnoea
Official title: Effects of Obstructive Sleep Apnoea and Its Treatment on Macrovascular and Microvascular Function
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Obstructive Sleep Apnoea
Obesity
Lead sponsor: Sheffield Teaching Hospitals NHS Foundation Trust
Sponsor class: OTHER
Collaborators: name: Sheffield Hallam University
First posted: 2012-06-14
Enrollment: 45
Sex: ALL
Minimum age (years): 18
Maximum age (years): 90
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: CASE_CONTROL
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Patients and controls living in and around Sheffield, UK

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

Detailed 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.

Eligibility criteria: 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

Primary outcomes:
measure: Flow-mediated dilatation of the brachial artery
timeFrame: Baseline only
Secondary outcomes:
measure: GTN-mediated dilatation of the brachial artery
timeFrame: Baseline only
measure: Forearm skin blood flow response to 5-min proximal-cuff arterial occlusion
timeFrame: Baseline only
measure: Forearm skin blood flow response to localised heating at 42 degrees C
timeFrame: Baseline only
Other outcomes:
Locations:
city: Sheffield
country: United Kingdom
facility: Centre for Sport and Exercise Science, Sheffield Hallam University
state: South Yorkshire
city: Sheffield
country: United Kingdom
facility: Sheffield Teaching Hospitals NHS FT
state: South Yorkshire
Study officials:
affiliation: Sheffield Hallam University
name: Garry A Tew, PhD
role: STUDY_DIRECTOR
affiliation: Sheffield Hallam University
name: James Moss, BSc
role: PRINCIPAL_INVESTIGATOR
affiliation: Sheffield Teaching Hospitals NHS FT
name: Stephen Bianchi, MD
role: STUDY_DIRECTOR
References: