Sleep Apnea and Refractory Hypertension: Prevalence and Effect of CPAP Treatment

Study Overview
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Brief Summary
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A small number of uncontrolled studies have shown a high prevalence of sleep apnea in patients with refractory hypertension and that CPAP treatment achieves a significant reduction of blood pressure in the short term. The purpose of this study is to assess the prevalence of sleep apnea in patients with refractory hypertension, and the effects of continuous positive pressure treatment on systemic blood pressure and on serum markers of endothelial dysfunction and angiogenesis.

Detailed Description
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We assess the prevalence of an apnea hypopnea index (AHI) > 5 in patients with refractory hypertension referred from a hypertension clinic. Patients with an AHI >15 are randomized to either continuing their usual pharmacological treatment alone or adding CPAP to their usual treatment, during a 3 month period. The main endpoint is the comparison of the mean 24h systolic and diastolic blood pressure, as assessed by ambulatory blood pressure monitoring, between both treatment arms. The secondary endpoint is to assess changes in serum markers of endothelial dysfunction and angiogenesis

Official Title
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Sleep Apnea in Patients With Refractory Hypertension: Study of the Prevalence and the Effect of CPAP Treatment on Blood Pressure Control, Endothelial Dysfunction and Angiogenesis.

Conditions
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Hypertension, Sleep Apnea

Intervention / Treatment
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* Device: cpap treatment during sleep


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients referred from a tertiary hospital hypertension clinic with a diagnosis of refractory hypertension on the basis of office blood pressure higher then 160/90 mmHg despite the recommended doses of at least 3 drugs, including a diuretic. Exclusion Criteria: Causes of secondary hypertension, history of alcohol abuse , renal insufficiency, severe chronically illness.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: 1 CPAP<br>Nasal continuous positive airway pressure | Device: cpap treatment during sleep<br>* CPAP<br>|
| No Intervention: 2<br>Pharmacological treatment alone | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Effect of 3 months of CPAP versus conventional pharmacological treatment on the mean 24 h systolic and diastolic blood pressure . |  | 3 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Effect of CPAP versus conventional pharmacological treatment on inflammatory, endothelial function and angiogenesis serum biomarkers |  | 3 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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sleep apnea, refractory hypertension, continuous positive airway pressure