Cohort study of sleep quality in adult patients with acute pulmonary exacerbations of cystic fibrosis

Background: The impact of an acute pulmonary exacerbation of cystic fibrosis (CF) on sleep quality has not been established. Patients have greater burden of symptoms, higher intensity of therapy and are often admitted to hospital outside of their usual sleeping environment. Aims: To evaluate the prevalence of, and factors associated with, poor sleep quality in adult patients admitted to hospital with an acute exacerbation of CF lung disease. Methods: This prospective, observational study determined the prevalence of impaired sleep quality and associated factors in adult patients admitted to a single CF unit with an acute pulmonary exacerbation of CF. Sleep quality was defined by the Pittsburgh Sleep Quality Index (PSQI), with >5 indicating poor sleep quality. Data were obtained through patient questionnaires, chart review and examination. Results: Sixty-six percent of patients had impaired sleep quality. Patients with poor sleep had more sleep disruption due to pain (median response ‘mild sleep disruption’ vs ‘no sleep disruption’; P = 0.003) and insomnia (mean Insomnia Severity Index (ISI) 13 vs 5; P < 0.001). In patients with symptoms of restless legs, poor sleepers had worse symptoms (mean International Restless Legs Severity Score (IRLSS) 15 vs 5; P = 0.029). Univariate modelling showed relationships between PSQI and symptoms of depression and anxiety as well as with sleep disruption due to pain, general noise and nursing observations. In a multivariable model, ISI was the only variable that remained significantly associated with PSQI. Mean PSQI score increased 0.58 units for each 1 unit increase in ISI (95% CI 0.42–0.73; P < 0.001). Conclusions: Poor sleep quality is common among patients admitted with an acute exacerbation of CF and is strongly associated with insomnia symptoms in this cohort