Study of the Relationships Between Refractory Hypertension, Overweight/Obesity and Sleep Apnea Syndrome - Full Text View

Sponsors and Collaborators:	University Hospital, Grenoble Fondation de Recherche sur l'Hypertension Arterielle, France
Information provided by:	University Hospital, Grenoble
ClinicalTrials.gov Identifier:	NCT00746902

Purpose

The purpose of the study is to investigate the links between blood pressure (BP), overweight or obesity, and sleep apnea syndrome (SAS), by studying a large cohort of subjects suffering from refractory hypertension.

Primary objective

To compare plasmatic leptin levels in patients suffering from refractory hypertension depending on whether or not they experience SAS.

Secondary objectives

To ascertain what determines the difference in plasmatic leptin concentrations in patients suffering from refractory hypertension depending on whether or not they experience SAS.
To characterise BP readings (from clinical and ambulatory (ABPM) measurements) in patients suffering from refractory hypertension depending on whether or not they experience SAS.
To characterise metabolic parameters (lipids, glycaemia, adiponectin) and sympathetic nervous system effectors (adrenaline, noradrenaline and metanephrines) in patients suffering from refractory hypertension depending on whether or not they experience SAS.
To characterise BP readings, metabolic parameters and sympathetic nervous system effectors in patients suffering from refractory hypertension according to the severity of the SAS (in those who experience this problem).
To study, in patients with both SAS and refractory hypertension, the impact of nasal continuous positive airway pressure (CPAP) treatment on BP readings, metabolic parameters and sympathetic nervous system effectors, by comparing those who are compliant with the CPAP regimen with those who are non-compliant.

Condition	Intervention	Phase
Refractory Hypertension	Device: nCPAP	Phase III

MedlinePlus related topics: High Blood Pressure Obesity Sleep Apnea

U.S. FDA Resources

Study Type:	Interventional
Study Design:	Treatment, Randomized, Single Blind (Subject), Placebo Control, Parallel Assignment, Efficacy Study
Official Title:	Study of the Relationships Between Refractory Hypertension, Overweight/Obesity and Sleep Apnea Syndrome

Further study details as provided by University Hospital, Grenoble:

Primary Outcome Measures:

leptinemia [ Time Frame: inclusion visit, visit month 3, visit month 6 or 9 ] [ Designated as safety issue: No ]

Secondary Outcome Measures:

BP readings (clinical and ABPM), metabolic parameters (lipids, glycaemia, adiponectin) and sympathetic nervous system effectors (adrenaline, noradrenaline and metanephrines). [ Time Frame: inclusion visit, visit month 3, visit month 6 or 9 ] [ Designated as safety issue: No ]

Estimated Enrollment:	130
Study Start Date:	June 2008
Estimated Study Completion Date:	February 2012
Estimated Primary Completion Date:	May 2011 (Final data collection date for primary outcome measure)

Arms	Assigned Interventions
1: Active Comparator Arm 1: Active nCPAP	Device: nCPAP Active nCPAP
2: Sham Comparator Arm 2 : Sham nCPAP	Device: nCPAP Active nCPAP

Detailed Description:

A number of factors predispose subjects to both hypertension and SAS, including overweight/obesity and hyperinsulinism. The pathogenesis of concomitant overweight/obesity and hypertension is multifactorial. There is an independent relationship between the degree of insulin resistance and the severity of SAS. A number of studies have suggested that hormones secreted by adipose tissue are involved in the pathogenesis of both hypertension and SAS, and overweight/obesity has been shown to be associated with elevated leptin levels coupled with reduced adiponectin levels.

Leptin is produced in adipose tissue and its levels rise with overweight/obesity due to peripheral resistance to its action. A number of studies have detected high leptinemia in both hypertensives and people suffering from SAS. Leptin may activate the sympathetic nervous system and promote SAS-related hypertension.

Adiponectin which is also produced in adipose tissue has beneficial activities, notably on atherogenesis. A relationship between hypertension and adiponectin has yet to be demonstrated.

Unlike leptin, adiponectin levels do not seem to be elevated in patients with SAS.

In terms of treatment, a number of studies have shown that CPAP has a positive effect on BP readings. Although this effect is modest, it is greater in subjects with SAS and rises with the severity of this condition. The effects of CPAP on plasmatic leptin and adiponectin levels are as yet unknown.

Eligibility

Ages Eligible for Study:	18 Years to 70 Years
Genders Eligible for Study:	Both
Accepts Healthy Volunteers:	No

Criteria

Inclusion Criteria:

Patients of either gender, of between 18 and 70
Suffering from refractory hypertension as defined by persistent clinical hypertension (> 140/90 mm Hg according to two different readings 24 hours apart) despite at least three classes of antihypertensive drugs (including a thiazide diuretic) at appropriate doses.
Recruited in the Cardiology Departments of the University Hospitals in Grenoble, Toulouse, Marseille and Poitiers, and in the Mozart Clinic in Paris.
Outpatients
Patients who have signed the consent form
Patients affiliated to or beneficiary of the social security system

Exclusion Criteria:

Failure to fulfil the inclusion criteria
Treated SAS, whatever the form of the treatment
Disease which might affect BP regulation, including Parkinson's disease, kidney or heart transplantation, dysautonomia, severe heart failure
Atrial fibrillation or regular extrasystole (> 10/minute)
Night- or shift-work
Pregnant and breast-feeding women
Patients under legal guardianship
Incarcerated patients or adults protected by the law
Hospitalised patients
Ongoing participation in another clinical research study

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00746902

Contacts

Contact: Jean-Philippe JPB BAGUET, Professor, PhD

0033476768480

JPBaguet@chu-grenoble.fr

Locations

France
University Hospital	Recruiting
Grenoble, France

Sponsors and Collaborators

University Hospital, Grenoble

Fondation de Recherche sur l'Hypertension Arterielle, France

More Information

Responsible Party:	Pr Jean-Philippe BAGUET ( University Hospital, Grenoble )
Study ID Numbers:	0803
Study First Received:	September 3, 2008
Last Updated:	September 3, 2008
ClinicalTrials.gov Identifier:	NCT00746902
Health Authority:	France: Afssaps - French Health Products Safety Agency

Keywords provided by University Hospital, Grenoble:

Refractory hypertension
Obstructive sleep apnea syndrome
Obesity
Leptinemia
RHOOSAS study

Study placed in the following topic categories:

Obesity
Sleep Apnea Syndromes
Apnea
Sleep Apnea, Obstructive
Respiration Disorders
Vascular Diseases
Dyssomnias
Sleep Disorders

Overweight
Sleep Disorders, Intrinsic
Body Weight
Signs and Symptoms
Respiratory Tract Diseases
Nutrition Disorders
Overnutrition
Hypertension

Additional relevant MeSH terms:

Pathologic Processes
Disease
Syndrome
Nervous System Diseases
Cardiovascular Diseases

ClinicalTrials.gov processed this record on January 14, 2009