OSA Recurrence in CPAP Withdrawal

Not Applicable

Completed

• Conditions: OSA
• Interventions: Other: CPAP withdrawal

• Registration Number: NCT03472612
• Lead Sponsor: Guy's and St Thomas' NHS Foundation Trust

Brief Summary

Continuous positive airway pressure (CPAP) therapy is the most effective Treatment for obstructive sleep apnoea (OSA ). However, adherence to CPAP is often limited. There are established and emerging treatment alternatives to CPAP available, however, they are usually less effective than CPAP. To develop novel treatment methods and to predict who will respond to which treatment, the mechanism underlying obstructive sleep apnoea and different patient types should be described. Especially the contribution of the upper airway function and central respiratory control should be studied for this purpose. In a prospective interventional study, patients with OSA effectively treated with CPAP will undergo physiologic measurements during a two week period off CPAP to define the pathophysiological mechanisms associated with OSA recurrence. This knowledge could facilitate individually tailored treatment and improve therapy adherence and patient outcomes.

Detailed Description

Obstructive sleep apnoea (OSA) is a highly prevalent sleep-related breathing disorder characterised by a repetitive collapse of the pharynx during sleep, which results in apnoea or hypopnoea associated with oxygen desaturations and arousal from sleep. Continuous positive airway pressure (CPAP) is the gold standard treatment. Treatment success depends on regular CPAP usage. However, low adherence to CPAP is a frequent problem. It has recently been shown that OSA does not re-occur immediately in all OSA patients upon CPAP therapy withdrawal and that there are different patterns of recurrence of OSA as indicated by repeated sleep studies. So far, the mechanisms of OSA recurrence upon CPAP therapy withdrawal are incompletely understood. Upper airway collapsibility and neuromuscular tone, pharyngeal oedema and inflammation, neural respiratory drive, sleep stage and position may play a role.

In a prospective interventional study, patients with OSA effectively treated with CPAP will undergo physiologic measurements during a two week period off CPAP to define the pathophysiological mechanisms associated with OSA recurrence. In particular, we will investigate the effects of CPAP withdrawal on neural respiratory drive and upper airway function. Inpatient sleep studies and assessments will be performed at baseline (day 0) on CPAP and at follow-up upon CPAP withdrawal (day 14). At the end of the trial patients will return to their established CPAP therapy.

We hypothesise that CPAP withdrawal results in different patterns of OSA recurrence defined by neural respiratory drive and upper airway function. The aim of the proposed project is to study the mechanisms of OSA recurrence by using a validated CPAP withdrawal model. Knowledge on recurrence patterns and different phenotypes of OSA could facilitate individually tailored treatment of OSA and improved therapy adherence and patient outcomes.

Study Timeline

• Study First Submitted: 2018-03-07
• Study First Submitted QC: 2018-03-14
• Study First Posted: 2018-03-21
• Study Start: 2018-04-09
• Primary Completion: 2019-06-30
• Study Completion: 2019-10-01
• Status Verified: 2022-03
• Last Update Submitted: 2022-03-14
• Last Update Posted: 2022-03-15

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 25

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
CPAP withdrawal	CPAP withdrawal	Short-term withdrawal of CPAP therapy in moderate to severe OSA (intervention)

Primary Outcome Measures

Name	Time	Method
Change in neural respiratory drive (NRD) during sleep upon CPAP therapy withdrawal	2 weeks	Electromyography of respiratory muscles as measure of neural respiratory drive

Secondary Outcome Measures

Name	Time	Method
Forced expiratory volume in 1 second	2 weeks	Spirometry
Home and office blood pressure	2 weeks	Blood pressure (mmHg)
Fatigue Severity Sclae (FSS)	2 weeks	Questionnaire for subjective sleepiness (Points)
Stanford Sleepiness Scale (SSS)	2 weeks	Questionnaire for subjective sleepiness (Points)
Pharyngeal critical occlusion pressure during sleep (Pcrit)	2 weeks	Measures of upper airway collapsibility (cmH2O)
Pharyngeal oedema	2 weeks	Transcervical ultrasound (mm)
Home and office heart rate	2 weeks	Heart rate (bpm)
Forced oscillation technique (FOT)	2 weeks	Measure of (upper) airway resistance
Negative expiratory pressure (NEP)	2 weeks	Measure of (upper) airway resistance and collapsibility (cmH2O)
Recurrence pattern of OSA defined by the nightly obstructive respiratory events (apnoea-hypopnoea-index)	2 weeks	Polysomnography (events/hour)
Epworth Sleepiness Scale Score (ESS)	2 weeks	Questionnaire for subjective sleepiness (Points)
Forced vital capacity	2 weeks	Spirometry
Recurrence pattern of OSA defined by the nightly obstructive respiratory events (oxygen desaturation index)	2 weeks	Nightly home pulse oximetry (events/hour)
Functional Outcomes of Sleep Questionnaire (FOSQ)	2 weeks	Quality of life questionnaire
Association between ODI (recurrence pattern of OSA) and neural respiratory drive (NRD)	2 weeks	Multivariate Regression modelling with ODI as dependent variable

Trial Locations

Locations (1)

Guys and St Thomas NHS Foundation Trust; 🇬🇧 London, United Kingdom