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Effects of Suboptimal CPAP Therapy on Symptoms of Obstructive Sleep Apnoea

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ClinicalTrials.gov Identifier: NCT02781740
Recruitment Status : Recruiting
First Posted : May 24, 2016
Last Update Posted : October 26, 2017
Sponsor:
Collaborator:
Swiss National Science Foundation
Information provided by (Responsible Party):
University of Zurich

Brief Summary:

Obstructive sleep apnoea (OSA) is a highly prevalent sleep-related breathing disorder. The most effective treatment for OSA is continuous positive airway pressure (CPAP). CPAP therapy has been shown to significantly reduce subjective sleepiness and blood pressure in patients with symptomatic OSA. Its effectiveness tends to depend on its nightly usage and a commonly held view is that CPAP should be used for at least 4h/night. However, previous studies have estimated that a considerable proportion of CPAP users fail to achieve this. In addition, there is inadequate evidence to support this apparent threshold effect and so it is unclear whether such patients actually benefit from treatment or whether they could be withdrawn from CPAP, thus substantially reducing health care costs, or encouraged to increase their nightly usage of CPAP.

The aim of the proposed project is to study the effect of CPAP withdrawal on subjective sleepiness in OSA patients using CPAP for less than 4h/night on average. We hypothesize that two-week CPAP withdrawal in patients with 3-4h/night use will lead to a return of OSA-related symptoms. This trial will better establish the minimum level of CPAP adherence which could generally be regarded as effective in reducing OSA-related symptoms.


Condition or disease Intervention/treatment Phase
Sleep Apnea, Obstructive Device: Continous Positive Air Pressure Device Not Applicable

Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 56 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double (Participant, Outcomes Assessor)
Primary Purpose: Other
Official Title: Effects of Suboptimal Use of CPAP Therapy on Symptoms of Obstructive Sleep Apnoea
Study Start Date : April 2016
Estimated Primary Completion Date : December 2019
Estimated Study Completion Date : February 2020

Resource links provided by the National Library of Medicine

MedlinePlus related topics: Sleep Apnea

Arm Intervention/treatment
Active Comparator: CPAP therapy
Continuation of the already established CPAP therapy.
Device: Continous Positive Air Pressure Device
Sham Comparator: Sham CPAP therapy
Sham-CPAP is achieved by setting the CPAP machine to the lowest pressure, insertion of a flow-restricting connector at the machine outlet, and insertion of six extra holes in the collar of the main tubing at the end of the mask to allow air escape and to prevent rebreathing of CO2.
Device: Continous Positive Air Pressure Device



Primary Outcome Measures :
  1. Epworth Sleepiness Scale (ESS) [ Time Frame: Change from baseline in ESS after 2 weeks of CPAP or sham-CPAP respectively. ]
    Standard, well-established Epworth questionnaire. Score values between 0 and 24 represent severity of daytime sleepiness.


Secondary Outcome Measures :
  1. Apnoea-Hypopnoea Index (AHI) [ Time Frame: Change from baseline in AHI after 2 weeks of CPAP or sham-CPAP respectively. ]
    AHI acquired non-invasively by respiratory polygraphy at baseline and after 2 weeks. Measured in events per hour it represents severity of sleep apnoea.

  2. Oxygen Desaturation Index (ODI) [ Time Frame: Change from baseline in ODI after 2 weeks of CPAP or sham-CPAP respectively. ]
    ODI acquired non-invasively by respiratory polygraphy at baseline and after 2 weeks. Measured in events per hour it represents severity of sleep apnoea.

  3. Mean CPAP usage time [ Time Frame: Measured at baseline and after 2 weeks of CPAP or sham-CPAP respectively. ]
    Acquired automatically by the CPAP/sham-CPAP devices over the course of 2 weeks. Measured in hours per night it represents treatment adherence.

  4. Heart rate [ Time Frame: Change from baseline in heart rate after 2 weeks of CPAP or sham-CPAP respectively. ]
    Resting heart rate acquired non-invasively during wakefulness following respiratory polygraphies at baseline and after 2 weeks. Measured in beats per minute (bpm).

  5. Mean blood pressure [ Time Frame: Change from baseline in mean blood pressure after 2 weeks of CPAP or sham-CPAP respectively. ]
    Mean resting blood pressure acquired non-invasively during wakefulness following respiratory polygraphies at baseline and after 2 weeks. Measured in mmHg.

  6. Fatigue Severity Scale (FSS) [ Time Frame: Change from baseline in FSS after 2 weeks of CPAP or sham-CPAP respectively. ]
    Standard, well-established FSS questionnaire. Score values between 7 and 63 represent severity of daytime fatigue.

  7. Quality of life as assessed in Short Form 36 (SF-36) [ Time Frame: Change from baseline in SF-36 after 2 weeks of CPAP or sham-CPAP respectively. ]
    Standard, well-established 36-item patient-reported survey of patient general health status.

  8. Quality of life as assessed in Functional Outcomes of Sleep Questionnaire 10 (FOSQ-10) [ Time Frame: Change from baseline in FOSQ-10 after 2 weeks of CPAP or sham-CPAP respectively. ]
    FOSQ-10 is a standard, well-established 10-item patient-reported survey of impact of disorders of excessive sleepiness on activities of daily living.

  9. Psychomotor vigilance as measured through the Oxford Sleep Resistance test (OSLER). [ Time Frame: Change from baseline in OSLER after 2 weeks of CPAP or sham-CPAP respectively. ]
    OSLER is a standard test consisting of one to three 40-min sessions assessing the patients ability of performing a repetitive task. The OSLER error index measured in events per hour correlates statistically with sleep latency.

  10. Psychomotor vigilance as measured through the Multiple Unprepared Reaction Time Test (MURT) [ Time Frame: Change from baseline in MURT after 2 weeks of CPAP or sham-CPAP respectively. ]
    MURT is a standard test consisting of two 10-min sessions assessing the patient's alertness. The MURT time measured in milliseconds represents the patients reaction time and correlates with sleep latency.



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Ages Eligible for Study:   20 Years to 75 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • Objectively confirmed OSA (at the time of original diagnosis) with an oxygen desaturation index (ODI, ≥4% dips) of ≥15/h and an ESS of >10.
  • Currently ≥15/h oxygen desaturations (≥4% dips) during an ambulatory nocturnal pulse oximetry performed at the end of a 4-night period without CPAP.
  • Eligible patients must have been treated with CPAP for more than 12 months with a mean compliance between 3 and 4h/night. Apnoea-hypopnoea index (AHI) must be less than 10 with treatment (according to CPAP machine download data).

Exclusion Criteria:

  • Previous ventilatory failure (awake PaO2<9.0kPa or arterial PaCO2>6kPa).
  • Unstable, untreated coronary or peripheral artery disease, severe arterial hypertension (>180/110mmHg).
  • Previously diagnosed with Cheyne-Stokes breathing.
  • Current professional driver.
  • Age < 20 or > 75 years at trial entry.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02781740


Contacts
Contact: Malcolm Kohler, Prof. Dr. med. +41 44 255 38 28 malcolm.kohler@usz.ch
Contact: Protazy Rejmer, med. pract. +41 44 255 49 47 protazy.rejmer@usz.ch

Locations
Switzerland
Pulmonary Division, University Hospital Zurich Recruiting
Zurich, Switzerland, 8091
Contact: Malcolm Kohler, Prof. Dr. med.    +41 44 255 97 51    malcolm.kohler@usz.ch   
Contact: Protazy Rejmer, med. pract.    +41 44 255 49 47    protazy.rejmer@usz.ch   
Principal Investigator: Malcolm Kohler, Prof. Dr. med.         
Sub-Investigator: Protazy Rejmer, med. pract.         
Sub-Investigator: Esther Irene Schwarz, Dr. med.         
Sponsors and Collaborators
University of Zurich
Swiss National Science Foundation
Investigators
Principal Investigator: Malcolm Kohler, Prof. Dr. med. University of Zurich

Responsible Party: University of Zurich
ClinicalTrials.gov Identifier: NCT02781740     History of Changes
Other Study ID Numbers: KEK-ZH-Nr.: 2016-00332
2015-MD-0037 ( Other Identifier: Swissmedic )
CIV-15-12-014246 ( Other Identifier: EUDAMED )
First Posted: May 24, 2016    Key Record Dates
Last Update Posted: October 26, 2017
Last Verified: October 2017

Keywords provided by University of Zurich:
Continous Positive Airway Pressure
CPAP
Sham CPAP
CPAP withdrawal
suboptimal CPAP

Additional relevant MeSH terms:
Apnea
Sleep Apnea Syndromes
Sleep Apnea, Obstructive
Respiration Disorders
Respiratory Tract Diseases
Signs and Symptoms, Respiratory
Signs and Symptoms
Sleep Disorders, Intrinsic
Dyssomnias
Sleep Wake Disorders
Nervous System Diseases