Treatment of Sleep-disordered Breathing in Patients With SCI

Number of nights positive airway pressure (PAP) was used >=4 hours during the first 90 days measured by remote monitoring. Scores range from 0 to 90 days. Higher scores indicate better outcome.

The Pittsburgh Sleep Quality Index (PSQI) is an 18-item questionnaire that assesses sleep quality and disturbances over the past month. The PSQI is sensitive for distinguishing normal and abnormal sleepers and has good test-retest reliability. The investigators will use the 3-factor scoring, which has been shown to have superior psychometric properties. This will be used as the main independent measure of sleep quality.

The component scores are summed to produce a global score (range 0 to 21). Higher scores indicate worse sleep quality

The questionnaire is composed of four domains: physical health, psychological health, social relationships and environment. It also includes one question on overall quality of life and one on general health. Importantly, items on this scale are not dependent on mobility, which is unlikely to change in patients with Spinal Cord Injury/Disease as a result of improved sleep. The WHOQOL-BREF scores correlate highly (.89 or above) with WHOQOL-100 scores, and demonstrate good discriminant validity, content validity, internal consistency and test-retest reliability. The four WHOQOL-BREF domain scores will be used as main outcome measure. The WHOQOL-BREF measures quality of life across 4 domains. The measure is calculated by summing the point values for the questions corresponding to each domain and then transforming the scores to a 0-100 point interval, higher score correspond to greater perceived quality of life

Spirometry is a simple bedside test used to evaluate lung function. Key spirometry values include forced vital capacity (FVC) and forced expiratory volume over 1 second (FEV1) and the absolute FEV1/FVC ratio. If the FVC and FEV1 are decreased, the absolute FEV1/FVC ratio distinguishes between obstructive and restrictive impairments. A normal absolute FEV1/FVC ratio suggest that restrictive ventilatory impairment may be present, and a reduced FEV1 and absolute FEV1/FVC ratio indicates an obstructive ventilator pattern. The investigators will use supine FVC and maximal inspiratory pressure (MIP) as the key outcome measures for respiratory function for this study, as these are the most representative of respiratory functioning during sleep.

The normal value for the FEV1/FVC ratio is above 0.75. Values lower than 0.70 are suggestive of airflow limitation with an obstructive pattern whilst in restrictive lung diseases, this ratio is normal or high.

The CHART is a measure of overall function. The scale is divided into five separate domain scores: Physical, Cognitive, Mobility, Occupation, and Social integration.

Each of the five domains scored from 0-100. higher number indicates better outcome.

The Patient Health Questionnaire-9 (PHQ-9) is a 9-item depression module in the PHQ (a self-administered diagnostic instrument for common mental disorders) which is part of the Primary Care Evaluation of Mental Disorders (PRIME-MD) suite of evaluation tools. The PHQ-9 aligns to the DSM-IV diagnostic criteria for depression and is widely used to screen for depression across VA. The PHQ-9 total score will be used to measure depressive symptom severity as an outcome.

As a severity measure, the PHQ-9 score can range from 0 to 27. Higher the value, worse the outcome.

The Flinders Fatigue Scale (FFS) is a 7-item fatigue rating scale used to measure general symptoms of fatigue. The FFS total score will be used as an outcome measure.

Total fatigue scores range from 0 to 31, with higher scores indicating greater fatigue.

The Epworth Sleepiness Scale (ESS) is a self-administered questionnaire that quantifies daytime sleepiness, with higher scores indicating increased daytime hypersomnolence The ESS is ranging from 0 to 24. higher scores indicate more sleepiness