Supplemental oxygen in OSA following CPAP withdrawal

Not Applicable

Completed

• Conditions: Topic: Respiratory disorders; Subtopic: Respiratory (all Subtopics); Disease: Respiratory; Respiratory

• Registration Number: ISRCTN17987510
• Lead Sponsor: niversity of Oxford

Brief Summary

2018 results in: https://www.ncbi.nlm.nih.gov/pubmed/30025470 2021 results in https://pubmed.ncbi.nlm.nih.gov/33991325/ (added 17/05/2021)

Detailed Description

Not available

Study Timeline

• Results First Posted: 1900-01-01
• Study Start: 2015-02-19
• Study Completion: 2016-12-31
• Last Update Posted: 7 June 2021

Recruitment & Eligibility

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

Inclusion Criteria

1. Objectively confirmed obstructive sleep apnoea (at the time of original diagnosis) with an oxygen desaturation index (ODI, =4% dips) of >20/h or/and an apnoea/ hypopnoea index of >20/h (this threshold will exclude subjects with borderline OSA, in whom there may be little treatment effect).
2. Currently >20/h oxygen desaturations (=4% dips) returning on any night during an ambulatory nocturnal pulse oximetry performed during a 4-night period without CPAP.
3. Treated with CPAP for more than 12 months, minimum compliance 4h per night, AHI <10 with treatment (according to machine download data) and ODI<10 confirmed on CPAP during screening oximetry.
4. Written informed consent
5. Upper Age Limit 75 years, lower Age Limit 20 years

Exclusion Criteria

1. Previous ventilatory failure (awake resting arterial oxygen saturation <93% or arterial PCO2 > 6kPa) or severe respiratory disorders other than OSA
2. Unstable, untreated coronary or peripheral artery disease, severe arterial hypertension (>180/110mmHg), severe arterial hypotension (<90/60mmHg).
3. Previously diagnosed with CheyneStokes breathing.
4. Current professional driver.
5. Any sleep related accident.
6. Age <20 or >75 years at trial entry.
7. Severe nasal congestion.
8. Mental or physical disability precluding informed consent or compliance with the protocol
9. Nonfeasible trial followup (for example, distance from follow-up centre, physical inability).
10. Current smoker

Study & Design

• Study Type: Interventional
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Home blood pressure change over 14 days; Timepoint: Home blood pressure measured every morning by the patient

Secondary Outcome Measures

Name	Time	Method
<br> 1. Home heart rate change over 14 days; Timepoint; home heart rate measured every morning by the patient<br> 2. Change in OSA severity: Timepoint: home sleep study measured before study visits 1, 2, 3, and 4<br> 3. Change in subjective (questionnaire ESS) and objective sleepiness (OSLER test); Timepoint: ESS and OSLER measured at study visits 1,2 3, and 4<br> 4. Change in overnight urinary catecholamine secretion; Timepoint: Overnight urine collection for catecholamines prior to visits 1, 2, 3, and 4<br> 5. Change in gene expression (mRNA and microRNA); Timepoint; Bloods samples at visits 1, 2, 3, and 4<br>