Condition category
Date applied
Date assigned
Last edited
Prospectively registered
Overall trial status
Recruitment status
No longer recruiting
Publication status
Results overdue

Plain English Summary

06/06/2019: This record contains out of date information and will not be updated further. Please see for the most up to date trial record.

Plain English summary not provided at time of registration.

Trial website

Contact information



Primary contact

Dr Yves Lacasse


Contact details

Centre de recherche de l’Institut de cardiologie et de pneumologie de Québec (CRICPQ)
Hôpital Laval
2725 Chemin Ste-Foy
G1V 4G5

Additional identifiers

EudraCT number number


Protocol/serial number


Study information

Scientific title

Multicentre randomised placebo-controlled trial of nocturnal oxygen therapy in chronic obstructive pulmonary disease



Study hypothesis

In patients with chronic obstructive pulmonary disease (COPD) not qualifying for long-term oxygenotherapy (LTOT) but who present significant nocturnal arterial oxygen desaturation, nocturnal oxygen (N-O2) provided for a period of 3 years is effective in decreasing mortality or delaying the requirement for LTOT, and is cost-effective and favorably compares to other medical interventions.

Ethics approval

Local medical ethics committee (Comité d'éthique de la recherche de l'Institut universitaire de cardiologie et de pneumologie de Québec [Hôpital Laval]) pending approval; meeting planned for 03/11/2009

Study design

Multicentre placebo-controlled randomised trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting


Trial type


Patient information sheet

Not available in web format, please use the contact details to request a patient information sheet


Chronic obstructive pulmonary disease (COPD)


Nocturnal oxygen therapy (N-O2 study group): oxygen delivered overnight to allow the oxygen saturation to be greater than 90%
Placebo (control group): room air delivered by defective concentrator

The comparison will be double blind. COPD patients will be randomly assigned to 3 years of treatment with either home N-O2 or sham therapy with ambient air. Each patient will be followed-up for this period of 3 years, with regular visits (every 4 months) until one of the following events: the patient is prescribed LTOT or the patient dies.

Intervention type



Not Applicable

Drug names

Primary outcome measure

1. Mortality from all cause
2. Requirement for LTOT (composite outcome)

The usual socio-demographic and clinical characteristics will be obtained at baseline. Spirometry will be performed according to the American Thoracic Society requirements, lung volumes measurement by plethysmography, and carbon monoxide diffusion capacity measurement by the single-breath method (all measured at baseline, 12, 24 and 36 months). All arterial blood gases will be measured while breathing at room air (measured at baseline and every 4 months until 36 months). In case of death, the date at which the primary outcome is reached will be obtained directly from chart review, contact with the treating physician or on the basis of interviews with surviving relatives during the protocol-based home visits or telephone interviews.

Secondary outcome measures

1. Quality of life and utility measures, measured at baseline, 12 months, 24 months and 36 months
2. Costs from a societal perspective, measured through telephone contacts with patients every two months
3. Compliance with oxygen therapy, measured at 4, 8, 12, 16, 20, 24, 28, 32 and 36 months

Overall trial start date


Overall trial end date


Reason abandoned (if study stopped)


Participant inclusion criteria

1. Patients with a diagnosis of COPD supported by a history of past or current smoking and obstructive disease: forced expiratory volume in one second (FEV1) less than 50% predicted, FEV1/forced vital capacity (FVC) less than 70% and a total lung capacity by body plethysmography greater than 80% predicted
2. Stable COPD at study entry for at least 6 weeks before enrolment in the trial, as demonstrated by:
2.1. No acute exacerbation
2.2. No change in medications
3. Non-smoking patients for at least 6 months before enrolment in the trial
4. Mild-to-moderate daytime hypoxaemia with a resting partial pressure of oxygen in arterial blood (PaO2) (room air) in the range of 56 - 69 mmHg
5. Patients fulfilling the current definition of nocturnal oxygen desaturation, i.e., greater than or equal to 30% of the recording time with transcutaneous arterial oxygen saturation less than 90% on at least one of two consecutive recordings
6. Ability to give informed consent
7. Men and women aged over 40 years of age

Participant type


Age group




Target number of participants


Participant exclusion criteria

1. Patients with severe hypoxaemia fulfilling the usual criteria for continuous oxygen (CONT-O2) at study entry: PaO2 less than or equal to 55 mmHg or PaO2 less than or equal to 59 mmHg with clinical evidence of at least one of the following:
1.1. Pulmonary hypertension
1.2. Right ventricular hypertrophy
1.3. Cor pulmonale
1.4. Haematocrit greater than or equal to 55%
2. Patients with proven sleep apnoea (defined by an apnoea/hypopnoea index of greater than or equal to 15 events/hour) or suspected sleep apnoea on oximetry tracings
3. Patients currently using nocturnal oxygen therapy (NO2)
4. Patients with known left heart or congenital heart diseases, interstitial lung diseases, bronchiectasis as the main cause of obstructive disease, lung carcinoma, severe obesity (body mass index greater than or equal to 40 kg/m^2), or any other disease that could influence survival

Recruitment start date


Recruitment end date



Countries of recruitment


Trial participating centre

Centre de recherche de l’Institut de cardiologie et de pneumologie de Québec (CRICPQ)
G1V 4G5

Sponsor information


Laval Hospital (Hôpital Laval) (Canada)

Sponsor details

c/o Dr Yves Lacasse
Centre de recherche de l’Institut de cardiologie et de pneumologie de Québec (CRICPQ)
2725 Chemin Ste-Foy
G1V 4G5
+1 (0)418 656 4747

Sponsor type

Hospital/treatment centre



Funder type

Research organisation

Funder name

Canadian Institutes of Health Research (CIHR) (Canada) (ref: MCT-99512)

Alternative name(s)

Instituts de Recherche en Santé du Canada, CIHR, IRSC

Funding Body Type

government organisation

Funding Body Subtype

National government



Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Basic results (scientific)

Publication list

2017 protocol in:
Results will be available at:

Publication citations

Additional files

Editorial Notes

06/06/2019: This record contains out of date information and will not be updated further. Please see for the most up to date trial record. 25/04/2019: Internal review. 11/01/2017: Publication reference added.