Effects of Continuous Positive Airway Pressure (CPAP) in Patients With Resistant Hypertension and Obstructive Sleep Apnea (OSA)

This study has been completed.
Sponsor:
Information provided by (Responsible Party):
Geraldo Lorenzi-Filho, University of Sao Paulo
ClinicalTrials.gov Identifier:
NCT00812695
First received: December 19, 2008
Last updated: November 21, 2011
Last verified: November 2011

December 19, 2008
November 21, 2011
October 2008
March 2011   (final data collection date for primary outcome measure)
Ambulatory blood pressure monitoring [ Time Frame: Change from Baseline in Blood Pressure at 6 months ] [ Designated as safety issue: Yes ]
Ambulatory blood pressure monitoring [ Time Frame: Baseline and 6 months ] [ Designated as safety issue: Yes ]
Complete list of historical versions of study NCT00812695 on ClinicalTrials.gov Archive Site
  • Change from Baseline in Arterial stiffness at 6 months [ Time Frame: baseline and 6 months ] [ Designated as safety issue: Yes ]
  • change from baseline in heart remodeling at 6 months [ Time Frame: baseline and 6 months ] [ Designated as safety issue: Yes ]
  • Arterial stiffness [ Time Frame: baseline and 6 months ] [ Designated as safety issue: Yes ]
  • Heart remodeling [ Time Frame: baseline and 6 months ] [ Designated as safety issue: Yes ]
Not Provided
Not Provided
 
Effects of Continuous Positive Airway Pressure (CPAP) in Patients With Resistant Hypertension and Obstructive Sleep Apnea (OSA)
Effects of Continuous Positive Airway Pressure in Patients With Resistant Hypertension and Obstructive Sleep Apnea

Obstructive sleep apnea (OSA) is an important cause of refractory hypertension but the impact of treatment with continuous positive airway pressure (CPAP) is not completely understood. The aim of this project is to study the effects of CPAP on blood pressure control and its influences on cardiac remodeling and arterial stiffness in patients with refractory hypertension and moderate or severe OSA.

Study design Interventional, open-label, randomized.

Patients selection

Fifty refractory hypertensive patients with moderate-to-severe OSA, aged between 30 to 65 years old will be recruited from the outpatient clinics of the Heart Institute by the hospital staff.

Refractory hypertension will be defined as usually: blood pressure higher than or equal to 140x90 mmHg after a regimen of three drugs, including a diuretic for a minimum of 3 months. Initial evaluation will consist on ambulatory blood pressure measurement for 24 hours and a detailed clinical examination. Moderate to severe OSA will be defined as an apnea-hypopnea index > 15 evens per hour, after an overnight polysomnography.

Exclusion criteria include BMI >40 kg/m2; diabetes mellitus; aortic, heart and valve diseases; renal failure; other identifiable causes of hypertension, no adherence, use of cocaine, amphetamines, other illicit drugs, sympathomimetics (decongestants, anorectics), oral contraceptive hormones, nonsteroidal anti-inflammatory drugs.

Refractory hypertension Secondary causes of hypertension will be excluded using usual procedures from the Hypertension Unit.

Polysomnography All participants will be submitted to standard overnight polysomnography (EMBLA - Flagra hf. Medical Devices, Reykjavik, Iceland). The apnea-hypopnea index will be calculated as the total number of respiratory events (apneas plus hypopneas) per hour of sleep.

Apnea will be defined as an air flow cessation greater than 10 seconds and hypopnea as a reduction grater than 50% with oxygen saturation fall grater than 4% or arousal.

After recruitment, patients will be instructed about CPAP working by an experimented professional and another polysomnography will be done to adjust pressures. Hour counter will be used to check the adherence to CPAP.

Intervention Patients will be divided in two groups: medical treatment plus CPAP or medical treatment alone for 6 months without drug dose changing.

Twenty-four hour blood pressure monitoring Twenty-four hour blood pressure monitoring (system SpaceLabs 90207) will be used in all patients in the beginning and at the end of the study.

Arterial Stiffness Carotid-femoral arterial stiffness will be determined by Complior.

Echocardiography Echocardiography will be performed by using a commercially available machine.

Interventional
Phase 3
Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Open Label
Primary Purpose: Treatment
  • Obstructive Sleep Apnea
  • Refractory Hypertension
Device: CPAP
Gold standard treatment for Obstructive sleep apnea
  • No Intervention: 1
  • Active Comparator: 2
    CPAP
    Intervention: Device: CPAP
Pedrosa RP, Drager LF, de Paula LK, Amaro AC, Bortolotto LA, Lorenzi-Filho G. Effects of OSA treatment on BP in patients with resistant hypertension: a randomized trial. Chest. 2013 Nov;144(5):1487-94. doi: 10.1378/chest.13-0085.

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Completed
40
March 2011
March 2011   (final data collection date for primary outcome measure)

Inclusion Criteria:

  • Refractory hypertensive patients with moderate-to-severe OSA, aged between 30 to 65 years old.

Exclusion Criteria:

  • Aortic, heart and valve diseases
  • Renal failure
  • Other identifiable causes of hypertension, no adherence, use of cocaine, amphetamines, other illicit drugs, sympathomimetics (decongestants, anorectics), oral contraceptive hormones, nonsteroidal anti-inflammatory drugs.
Both
30 Years to 65 Years
No
Contact information is only displayed when the study is recruiting subjects
Brazil
 
NCT00812695
RH-OSA
Yes
Geraldo Lorenzi-Filho, University of Sao Paulo
University of Sao Paulo
Not Provided
Not Provided
University of Sao Paulo
November 2011

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP