Sleep and Quality of Life in Cystic Fibrosis

Abstract

Cystic fibrosis (CF) is a progressive disorder. Patients face rigorous daily treatments and fears of an uncertain future, both of which can impact on the physical, social and psychological aspects of their lives. In addition, with ongoing lung damage and airway obstruction, hypoxemia and hypercapnia during sleep can develop, contributing to daytime physiological and neurocognitive deficits. Health-related quality of life (HRQoL) in CF has become increasingly important as patient survival has increased. As a result, CF-specific measures of HRQoL have been developed. Quality of life research suggests that, despite chronic symptoms of dyspnoea and cough, reduced functional capacity, and the burden of repeated respiratory infections and hospitalization, people with CF generally report a good HRQoL in the psychosocial domain. However, scores for most physical domains are lower than those seen in matched healthy controls. Many patients with CF perceive their quality of sleep to be poor, with those individuals with more severely impaired lung function and worse gas exchange more likely to report poorer subjective sleep quality. Sleep disturbance appears to be a major factor in the poor overall sleep quality that patients with CF report. Although hypoxia and hypercapnia might contribute to sleep disruption and impaired daytime function in the presence of severe lung damage, other mechanisms likely to contribute include cough, airway inflammation, sinusitis and gastrointestinal disturbances. Pulmonary exacerbations also adversely affect sleep quality, quality of life and cognitive function, but no cause-and-effect relationship between exacerbation-related sleep disturbance and quality of life and cognitive changes has been demonstrated. Although treatments such as oxygen and NIV can improve nocturnal gas exchange, little evidence of a long-term benefit on either quantity or quality of life in CF has yet been demonstrated. As survival increases, there will be increasing focus on issues such as sleep quality, its effects on daytime function and management of respiratory failure. Improving the impact of the illness and its treatments on quality of life will become an increasingly important goal for interventions in this patient group.