Efficacy of CPAP Treatment on Blood Pressure of Resistant Hypertension Patients With Obstructive Sleep Apnea Syndrome

Phase 4

Completed

• Conditions: Obstructive Sleep Apnea Syndrome; Resistant Hypertension
• Interventions: Procedure: Continuous positive airway pressure treatment

• Registration Number: NCT01508754
• Lead Sponsor: Universidade Federal do Rio de Janeiro

Brief Summary

The aim is to evaluate the effect of treatment with Continuous Positive Airway Pressure (CPAP) device on clinic and ambulatory blood pressures (BP) of 200 resistant hypertensive patients with moderate-severe obstructive sleep apnea syndrome (OSAS).

Detailed Description

Obstructive sleep apnea syndromes (OSAS) have been demonstrated to be highly prevalent in patients with resistant hypertension (defined as uncontrolled clinic BP despite being on anti-hypertensive treatment with at least 3 drugs in optimal doses and including a diuretic). Nevertheless, the effect of treating OSAS with Continuous Positive Airway Pressure (CPAP) device on clinic and ambulatory BPs in patients with resistant hypertension is largely unknown. Hence, the primary aim of this randomized clinical trial is to evaluate the effect of CPAP on BP levels in resistant hypertensive patients with moderate-severe OSAS (defined as an apnea-hypopnea index \[AHI\] greater than 15 on a full polysomnographic examination). Two-hundred patients will be randomly allocated either to treatment with CPAP device plus their usual anti-hypertensive treatment or to continue their usual treatment alone for 6 months. Clinic and 24-hour ambulatory BP monitoring, laboratory evaluation (including microalbuminuria and aldosterone-to-renin ratio), 24-hour Holter monitoring, ergospirometric treadmill test, and carotid-femoral pulse wave velocity measurement will be performed before and after the 6-month treatment, with the observers blinded to the allocation group.

Study Timeline

• Study Start: 2012-01
• Study First Submitted: 2012-01-05
• Study First Submitted QC: 2012-01-09
• Study First Posted: 2012-01-12
• Primary Completion: 2014-08
• Study Completion: 2014-08
• Status Verified: 2014-09
• Last Update Submitted: 2014-09-12
• Last Update Posted: 2014-09-15

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 125

Inclusion Criteria

• Patients with resistant hypertension and moderate-severe obstructive sleep apnea syndrome

Exclusion Criteria

• Older than 80 years
• Pregnant women
• Non-adherent to anti-hypertensive treatment
• Severe cognitive deficits

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
CPAP	Continuous positive airway pressure treatment	Treatment with Continuous Positive Airway Pressure

Primary Outcome Measures

Name	Time	Method
clinic and ambulatory blood pressures	6 months	Clinic and ambulatory blood pressures (during 24-hour ambulatory blood pressure monitoring, which included both daytime and nighttime blood pressures, as well as the nocturnal dipping pattern).

Secondary Outcome Measures

Name	Time	Method
Aldosterone excess measurements	6 months	Serum aldosterone concentration, plasma renin activity, aldosterone-to-renin ratio and 24-hour urinary aldosterone excretion.
Arterial stiffness	6 months	Carotid-femoral pulse wave velocity and aortic pulse wave contour analysis (which include aortic systolic and pulse pressure and augmentation index)
Autonomic system measurements	6 months	Measures of autonomic system balance derived from 24-hour Holter monitoring, which includes heart rate variability on time and frequency domains.
Cardiorespiratory fitness	6 months	Cardiorespiratory fitness by 6 min walking test with maximum oxigen consumption measurement and by complete ergospirometric treadmill test.
Microalbuminuria	6 months	Urinary albumin excretion rate on 24-hour urine collection

Trial Locations

Locations (1)

Program of Arterial Hypertension, University Hospital Clementino Fraga Filho; 🇧🇷 Rio de Janeiro, Brazil