Sleep Quality and Quality of Life in Patients With COPD

Abstract

PURPOSE: Sleep disorders are common in COPD patients, particularly coexisting Obstructive sleep apnoea (OSA). These patients also experience reduced health-related quality of life (HRQoL) caused by dyspnoea, systemic effects and co-morbidities. There is insufficient data assessing sleep quality and quality of life from our region. In this study, we explored quality of sleep in COPD patients without suspected OSA and the relationship between sleep quality and quality of life in these patients. METHODS: In this cross sectional descriptive study performed in a tertiary care hospital, 120 COPD patients completed questionnaires: Berlin questionnaire, Pittsburgh Sleep Quality Index, and St. George Respiratory questionnaires (SGRQ). Patients with suspected OSA were excluded on the basis of result of Berlin questionnaire. Pulmonary function test was done to categorize the patients into 3 groups of mild, moderate and severe COPD based on GOLD guidelines. Student's t-test and ANOVA were used to assess differences in continuous variables between groups (different severities of COPD and patients sex). Association between categorical variables was determined by Chi-square test. Logistic regression analysis was used to investigate the relationship between quality of life as dependent variable and other independent variables. RESULTS: Baseline mean values were: age 61.3 +/- 11.2, 56% female, BMI 24.1 +/- 4.5 kg/m2, FEV 1.59 +/- 1.4 litres. 68.8% had poor sleep quality (PSQI 8.1 +/- 6). Quality of sleep was significantly correlated with quality of life (p<0.001). Significant differences were found between the genders for total score and each of three subscores of SGRQ suggesting poorer quality of life in females. Stepwise multiple regression analysis showed that severity of COPD, female gender and sleep quality accounted for the poor quality of life significantly (r2 = 0.11, 0.2, and 0.16, respectively). CONCLUSIONS: Quality of sleep in patients with COPD is poor and worsens with disease progression. The low quality of sleep has an effect on the deterioration of their quality of life, especially in female patients.