General quality of life: SF-36
Mean difference in the seven other following SF-36 subscales between groups:
Vitality (VT)
physical functioning (PF)
bodily pain (BP)
Role-physical (RP)
Role-emotionale (RE)
Social functioning (SF)
Mental health (MH)
Each subscale ranges from 0 to 100. The higher the score, the better quality of life.
Specific quality of life: Calgary Sleep Apnea Quality of Life Index (SAQLI)
Mean difference in the SAQLI global score and score in the domain A, B, C and D between groups.
The SAQLI is a 35-items instrument that captures the adverse impact of sleep apnea on 4 domains:
Daily functioning (A)
Social interactions (B)
Emotional functioning (C)
Symptoms (D)
When the SAQLI is administered after a therapeutic intervention, a fifth domain (E) is completed (Treatment-related symptoms).
Items are scored on a 7-point scale with "all of the time" and "not at all" being the most extreme responses. Item and domain scores are averaged to yield a composite total score between 1 and 7. Higher scores represent better quality of life.
To obtain the global SAQLI score the sum of the mean domain scores A, B, C, and D is divided by 4. If Domain E has been used after a therapeutic intervention, the SAQLI score is obtained by summing the mean domain scores A, B, C, and D, subtracting the mean Domain E score and dividing by 4.
Daytime excessive sleepiness
Mean difference in the Epworth Sleepiness Scale (ESS) score between groups. The ESS is a 8-item questionnaire. ESS score can range from 0 to 24. The higher the ESS score, the higher daytime sleepiness.
Subjective sleep quality
Mean difference in the Pittsburgh Sleep Quality Index (PSQI) score between groups.
The PSQI is a 19-item questionnaire which measures several different aspects of sleep, offering seven component scores and one composite score. The component scores consist of subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleeping medication, and daytime dysfunction.
Each item is weighted on a 0-3 interval scale. The global PSQI score is then calculated by summing the seven component scores, providing an overall score ranging from 0 to 21, where lower scores denote a healthier sleep quality.
Mood
Mean difference in the Hospital Anxiety Depression Scale (HADS) score between groups.
The HADS is a 14-item questionnaire. Seven of the items relate to anxiety and seven relate to depression. Each item on the questionnaire is scored from 0-3. Scores range from 0 to 21 for either anxiety or depression. The higher the scores, the more anxiety and depression symptoms are important.
Depression
Mean difference in the Beck depression inventory (BDI) score between groups. The BDI is a 21-item questionnaire which assess the severity of depression. Score range from 0 to 63. Higher values represent a worse outcome.
Fatigue
Mean difference in the Pichot scale score between groups. The Pichot Scale is a 8-item questionnaire to assess fatigue. The score ranges from 0 to 32. Higher score indicates greater fatigue.
Blood pressure
Mean difference in systolic and diastolic blood pressure measured at office as well as via a 24-h ambulatory blood pressure monitoring
Weight
Mean difference in weight (kg) between groups
Height
Mean difference in height (m) between groups
Body-mass index (BMI)
Mean difference in BMI (kg.m^2) between groups. Weight will be divided by the square of the height to report BMI in kg/m^2.
Waist circumference
Mean difference in waist size (cm) between groups
Hip circumference
Mean difference in hip size (cm) between groups
Waist-hip ratio
Mean difference in waist/hip ratio between groups
Neck size
Mean difference in neck circumference (cm) between groups
Fat distribution
Mean difference in fat-free mass and fat mass measured via bioimpedance analysis between groups
Resting metabolism
Mean difference in basal metabolic rate (BMR) between groups using indirect calorimetry
Concentration of fasting glucose
Mean difference in fasting glucose (mg/dL) between groups
Rate of glycosylated haemoglobin
Mean difference in glycosylated haemoglobin [HbA1c] (%) between groups
Concentration of insulin
Mean difference in insulin (mlU/L) between groups
Concentration of total cholesterol
Mean difference in total cholesterol (g/L) between groups
Concentration of HDL cholesterol
Mean difference in HDL cholesterol (g/L) between groups
Concentration of LDL cholesterol
Mean difference in LDL cholesterol (g/L) between groups
Concentration of triglycerides
Mean difference in triglycerides (g/L) between groups
Concentration of ultrasensible CRP
Mean difference in CRP-US (mg/L) between groups
Respiratory events
Mean difference in apnea-hypopnea index (AHI) during sleep between groups measured via ambulatory polygraphy
Desaturation events
Mean difference in oxygen desaturation index (ODI) during sleep between groups measured via ambulatory polygraphy
T90%
Mean difference in percentage time spent with an oxygen saturation (SpO2) < 90% (T90%) during sleep between groups using an oximeter.
Nocturnal hypoxic load
Mean difference in hypoxic load related to apnea-hypopnea events and to sleep stages between groups using an ambulatory polygraphy. The area under the desaturation curve (SpO2) associated with respiratory-events will be used to quantify the 'hypoxic load'.
Autonomic Arousal Index (Aai)
Mean difference in pulse wave amplitude (PWA) drop during sleep between groups using an ambulatory polygraphy
Autonomic Arousal Area under the curve
Mean difference in the sum of the autonomic arousal area under the curve (AUC) between groups using an ambulatory polygraphy
Autonomic Arousal duration
Mean difference in the sum of the duration of the PWA drops between groups using an ambulatory polygraphy
CPAP withdrawal
Proportion of CPAP withdrawal in each arms
CPAP adherence
Mean duration of CPAP use per night in each arms
CPAP compliance
Proportion of compliant patients (mean CPAP use > 4h per night) in each arm
Medical visit
Mean number of medical visits between groups
Sedentary behaviour
Mean difference in sedentary time (min per day) between groups using accelerometer
Light physical activity (LPA) behaviour
Mean difference in LPA time (min per day) between groups using accelerometer
Moderate to vigorous physical activity
Mean difference in MVPA (METs-min per week) between groups using accelerometer
Exercise capacity
Mean difference in the distance (m) on the incremental shuttle walking test (ISWT) between groups
Postural stability
Mean difference in balance stability (total displacement of the centre of pressure) between groups using a posturographic platform