Sleep quality in Chinese patients with rheumatoid arthritis: contributing factors and effects on health-related quality of life

Background: Poor sleep quality is common in rheumatoid arthritis (RA) patients and may lead to disease aggravation and decreased health-related quality of life (HRQoL). The increasing prevalence of poor sleep in RA patients is associated with adverse demographic, clinical, and psychological characteristics. However, there are currently no known reported studies related to the effects of sleep quality on HRQoL in RA patients from China. This cross-sectional study aims to evaluate the contributors of poor sleep and the effects of sleep quality on HRQoL in Chinese RA patients. Methods: A self-report survey was administered to 131 RA patients and 104 healthy individuals using the Pittsburgh Sleep Quality Index (PSQI) for sleep quality. RA patients completed the Hospital Anxiety and Depression Scale for anxiety and depression, the 28-joint Disease Activity Score for disease activity, the 10 cm Visual Analog Scale for pain, the Health Assessment Questionnaire-Disability Index for functional capacity and the Short Form 36 health survey for HRQoL. Blood samples were taken to gain some biochemical indicators (e.g., erythrocyte sedimentation rate, C-reactive protein, rheumatoid factor, and anti-cyclic citrullinated peptide). Independent samples t-tests, Chi square analysis, logistic regression modeling and linear regression were used to analyze these data. Results: Our results found that the prevalence of poor sleep (PSQI >= 5) was 78.6% and the mean global score of PSQI was 7.93 (SD 3.98) in patients, which were significantly higher than the controls (18.7% and 3.88 (SD 1.89), respectively). There were significant correlations among synthetic disease-modifying antirheumatic drugs, erythrocyte sedimentation rate, pain, disease activity, functional capacity, anxiety/depression and sleep quality in RA patients. Meanwhile, logistic regression models identified disease activity and depression as predictors of poor sleep quality. Poor RA sleepers had impaired HRQoL than good RA sleepers, and sleep quality was independently and significantly associated with social function and mental components summary. Conclusions: The majority of Chinese RA patients suffered from poor sleep, which significantly impairs their HRQoL. The data suggested the need for holistic assessment and management of RA patients and the importance of objective interventions to improve their sleep quality and finally to improve their HRQoL.