Effect of Continuous Positive Airway Pressure (CPAP) Therapy on Changes of Blood Pressure Between Day and Night

Changes In Diurnal Blood Pressure Pattern In Obstructive Sleep Apnea (OSA) Patients After CPAP Therapy

to test whether using CPAP can restore the normal pattern of drop of blood pressure during sleep.

Study Overview

• Status: Terminated
• Conditions: Obstructive Sleep Apnea; Diurnal Blood Pressure

Detailed Description

OBJECTIVE:

To investigate the effect of CPAP therapy on the restoration of the normal diurnal blood pressure pattern. Possible improvement of the circadian dipper pattern after CPAP therapy, with or without a decrease in the mean blood pressure, might constitute an additional potential benefit of CPAP therapy in reducing cardiovascular risk in patients with OSA.

STUDY DESIGN AND METHODS:

Patients diagnosed with OSA at the sleep center will undergo blood pressure monitoring by measuring the blood pressure every half hour during sleep study. Patients with normal circadian BP changes are treated with CPAP as indicated. Patients with non-dipping BP pattern will be approach to join our study. The patients will receive CPAP therapy. The trial period will be 6 weeks. At the end of the trial, the patients from both treatment arms will undergo a second BP monitoring according to our above-mentioned protocol (systolic, diastolic and mean BP) to determine the circadian BP changes. Apnea-Hypopnea index will be calculated to reflect on the compliance with our therapy. Thus, patients could be divided into two study groups according to their objective compliance.

Baseline population characteristics between the placebo group and CPAP group will be noted. These include apnea-hypopnea index (AHI), medications, other co morbidities and other factors that might affect the normal circadian BP dipping pattern including factors affecting the volume status i.e. diabetes, renal failure, uncontrolled diabetes. Any new medications added during the 6 weeks trial period will be noted.

STATISTICAL ANALYSIS:

The difference in daytime and nighttime BP pattern will be noted between the treated (CPAP) and the non-compliant groups. The circadian BP variation will be recorded in both groups. Changes in the circadian BP pattern will be assessed on an intention-to-treat basis. The odds ratio, p value and confidence interval will be calculated. Correlation between the dipping/non-dipping pattern with CPAP compliance, severity of OSA and number of antihypertensive drugs will be studied as well

• Study Type: Observational
• Enrollment (Actual): 2

Contacts and Locations

Study Locations

• United States
  • New York
    • Staten Island, New York, United States, 10305
      • Heart Tower

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

Obstructive sleep apnea patients age over 18 years

Description

Inclusion Criteria:

1. All patients with OSA who don't meet the above mentioned exclusion criteria

Exclusion Criteria:

1. Patients who have a normal diurnal sleep pattern (i.e. decrease of more than 30% of the systolic BP at night time)
2. Patients who are on three or more antihypertensives whose blood pressure is not controlled.
3. Patients previously treated with CPAP therapy within the past 3 months

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
1; Compliant with CPAP
2; noncompliant with CPAP

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Time Frame
drop of Blood pressure at night	6 weeks

Collaborators and Investigators

• Sponsor: Northwell Health
• Collaborators: Staten Island University Hospital
• Investigators: Principal Investigator: Suzzane El-Sayegh, MD, Staten Island University Hospital

Study record dates

Study Major Dates

• Study Start: July 1, 2008
• Primary Completion (Actual): November 1, 2008
• Study Completion (Actual): November 1, 2008

Study Registration Dates

• First Submitted: December 26, 2008
• First Submitted That Met QC Criteria: May 28, 2013
• First Posted (Estimate): May 31, 2013

Study Record Updates

• Last Update Posted (Estimate): May 31, 2013
• Last Update Submitted That Met QC Criteria: May 28, 2013
• Last Verified: May 1, 2013

More Information

Terms related to this study

• Keywords: obstructive sleep apnea; CPAP; diurnal blood pressure; 24 hour blood pressure monitor
• Additional Relevant MeSH Terms: Nervous System Diseases; Respiratory Tract Diseases; Respiration Disorders; Sleep Disorders, Intrinsic; Dyssomnias; Sleep Wake Disorders; Signs and Symptoms, Respiratory; Sleep Apnea Syndromes; Sleep Apnea, Obstructive; Apnea
• Other Study ID Numbers: 07-057