Cardio-pulmonary Rehabilitation and Its Impact on Sleep Quality; a Prospective Analysis

Sleep disorders including poor quality of sleep are common in patients with heart failure, chronic obstructive pulmonary disease (COPD) and, possibly, other chronic lung disorders. These patients complain of difficulty sleeping and sleep fragmentation, often related to symptoms such as cough, sputum production or shortness of breath. Patients with COPD and heart failure commonly have other abnormalities such as nocturnal oxygen desaturation that may further worsen sleep disturbances. Moreover, sleep disordered breathing (SDB), like obstructive sleep apnea syndrome (OSA), has been linked to higher morbidity and mortality if COPD is present (known as Overlap syndrome). In patients with COPD and heart failure, cardio-pulmonary rehabilitation has important health benefits such as improvement in disease related symptoms, exercise tolerance, and health-related quality of life. However, the effect of cardio-pulmonary rehabilitation on sleep quality is controversial. Disturbed sleep is associated with frequent exacerbations, increase in the severity of disease and increased mortality in COPD and heart failure patients.

The investigators hypothesize that cardio-pulmonary rehabilitation results in improved sleep quality in patients with chronic lung disease and heart failure, this may be an important contributor to improved health outcomes after completion of cardio-pulmonary rehabilitation program.

The study will use data from questionnaires filled by the patients before and after completion of cardio-pulmonary rehabilitation. A 3-month follow up survey using the same questionnaires will be conducted to determine the longevity of improved sleep quality (if present). The questionnaires that will be used include Pittsburgh sleep quality index (PSQI), Epworth sleepiness scale (ESS), Berlin questionnaire, COPD assessment test (CAT) for COPD patients, Kansas city cardiomyopathy questionnaire (KCCQ) for heart failure patients, hospital induced anxiety and depression scale (HADS) and insomnia severity index (ISI).