Impact of CPAP Therapy in Obstructive Sleep Apnea on Parameters of Nocturnal Pulse Wave Analysis

October 26, 2018 updated by: Wissenschaftliches Institut Bethanien e.V
The present study aims to document and assess changes in single parameters of pulse wave analysis (ASI single parameters) as well as to evaluate ASI cardiovascular risk assessment before initiation of CPAP therapy and after 6 months of CPAP therapy in patients with obstructive sleep apnea.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Detailed Description

Obstructive sleep apnea (OSA) is characterized by repeated occurrence of apneas or reduced inspiratory air flow due to obstructions of the upper airways (hypopneas). These recurring events are accompanied by intermittent hypoxemia and sympathetic activation, leading to hemodynamic oscillations including relevant variations of pulse wave and blood pressure. Thus, OSA is associated with cardiovascular diseases and was identified as an independent risk factor for hypertension.

Direct effects of obstructive respiratory events (obstructive apneas and hypopneas) include changes of the peripheral pulse wave. The latter can easily be measured by finger plethysmography, e.g. by using established pulse oximeters. Certain pulse wave characteristics and their reaction towards obstructive respiratory events may provide information on cardiovascular function and thereby help in individual cardiovascular risk assessment.

Recently, Grote et al. published a concept for cardiovascular risk assessment based on pulse oximetry and pulse wave analysis ("ASI" - Grote et al. 2011, CHEST). The algorithm described herein is able to differentiate between high and low risk patients according to ESH/ESC risk classification (high risk = 4 and 5, low risk 1-3). To that end, oxygen saturation as measured by pulse oximetry, reductions in pulse wave amplitude, pulse rate accelerations, pulse propagation time and cardiorespiratory coupling are taken into account to calculate a quantitative total risk.

A successful OSA therapy applying positive airway pressure (e.g. CPAP) normalizes sleep-related breathing disturbances and thus counterbalances hemodynamic oscillations. This presumably results in reduced cardiovascular risk and should be detectable by measurable changes in pulse wave. This study aims to evaluate these effects by analyzing the single pulse wave parameters, which are part of the ASI algorithm. At the same time, established risk factors as well as the objective therapy outcome will be documented from the established sleep medicine viewpoint.

Study Type

Interventional

Enrollment (Actual)

314

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • Germany
      • Solingen, Germany, 42699
        • Bethanien Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  • Sleep-related breathing disorders with an apnea-hypopnea index ≥15/h and <30% central respiratory events (OSA patients)
  • Stable optimal medication according to European Society of Cardiology guidelines (if applicable)

Exclusion Criteria:

  • Prior exposure to positive airway pressure treatment
  • Atrial fibrillation
  • Facial anomalies or injuries inhibiting proper mask fit
  • Pregnancy and/or lactation
  • Acute life-threatening illness (e.g. instable angina pectoris, acute bronchial asthma, heart failure New York Heart Association stage IV, myocardial infarction, exacerbated Chronic obstructive pulmonary disease, malignant tumor requiring treatment)
  • Drug or alcohol abuse
  • Intake of hypnotics/sedatives
  • Any medical, psychological or other condition impairing the patient's ability to provide informed consent

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Basic Science
  • Allocation: N/A
  • Interventional Model: Single Group Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: 6 months CPAP
Application of continuous positive airway pressure (CPAP) therapy as established per routine clinical treatment. Home use of therapy for a period of 6 months.
Device: 6 months CPAP

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in pulse wave attenuation index
Time Frame: 6 months
The pulse wave attenuation index represents the number of decreases of the pulse wave amplitude >10% and <30% compared with baseline (a moving median value of 20 samples surrounding the observed sample). This number is given as attenuations per hour. The difference from baseline (without therapy) to 6 months (on CPAP therapy) is calculated.
6 months

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in mean pulse propagation time
Time Frame: 6 months
The pulse propagation time represents the time interval between the systolic and dicrotic notch of the pulse wave form. The mean pulse propagation time of a complete recording is documented. The difference from baseline (without therapy) to 6 months (on CPAP therapy) is calculated.
6 months
Change in mean respiration-related pulse oscillation
Time Frame: 6 months
The respiration-related pulse oscillation is calculated by measuring the breathing-associated oscillation (respiratory sinus arrhythmia in the frequency band between 0.15 and 0.4 Hz) from the pulse rate signal in the time domain. The mean respiration-related pulse oscillation value of a complete recording is documented. The difference from baseline (without therapy) to 6 months (on CPAP therapy) is calculated.
6 months
Change in pulse rate acceleration index
Time Frame: 6 months
The pulse rate acceleration index represents the number of pulse rate increases ≥10% from baseline (a moving median value of 20 samples surrounding the observed sample). This number is given as increases per hour. The difference from baseline (without therapy) to 6 months (on CPAP therapy) is calculated.
6 months
Change in hypoxia index
Time Frame: 6 months
The hypoxia index represents the number of oxygen desaturation events per hour. A desaturation event is defined as a ≥2% drop of saturation of each sample compared with a 90 seconds time window of the upcoming SpO2 signal. The difference from baseline (without therapy) to 6 months (on CPAP therapy) is calculated.
6 months
Change in ASI cardiovascular risk score
Time Frame: 6 months
The ASI algorithm described by Grote et al. (2011) combines several single parameters from pulse wave analysis to calculate an overall cardiovascular risk score. The difference from baseline (without therapy) to 6 months (on CPAP therapy) is calculated.
6 months

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Wissenschaftliches Institut Bethanien e.V

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

March 4, 2013

Primary Completion (Actual)

May 30, 2017

Study Completion (Actual)

May 30, 2017

Study Registration Dates

First Submitted

March 11, 2013

First Submitted That Met QC Criteria

March 19, 2013

First Posted (Estimate)

March 20, 2013

Study Record Updates

Last Update Posted (Actual)

October 30, 2018

Last Update Submitted That Met QC Criteria

October 26, 2018

Last Verified

October 1, 2018

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • WI_ASIC+CPAP_121/2012

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

Clinical Trials on Obstructive Sleep Apnea

Clinical Trials on 6 months CPAP

Search Similar Trials

Sponsors and Collaborators

Medical Conditions

Drug Interventions

CROs by country

CROs in Guinea

Conditions

Rare Diseases

Drug Interventions

Dietary Supplements

Sponsor/Collaborators

Locations

3
Subscribe