Sleep quality in patients with systemic sclerosis: relationship between the clinical variables, depressive symptoms, functional status, and the quality of life.

The aim of this study is to evaluate the relationship between the sleep quality and the disease-related variables, functional status, quality of life, and depressive symptoms in patients with systemic sclerosis (SSc). Forty-eight patients diagnosed with SSc and 42 healthy control subjects were enrolled in the study. The demographic and clinical characteristics of the patients such as the Raynaud's phenomenon, SSc subtype, digital ulcers, gastrointestinal and lung involvement, and disease activity were recorded. All patients were assessed using the short form 36 (SF-36) quality of life scale, the health assessment questionnaire and the beck depression inventory. Generalized pain and fatigue were assessed with the Visual Analoge Scale. For the evaluation of the sleep disturbance, the SSc and control groups were assessed with the help of the Pittsburgh Sleep Quality Index (PSQI). The patients with SSc had significantly higher scores in the subjective sleep quality, sleep latency, habitual sleep efficiency, sleep disturbance, daytime dysfunction domains, and in terms of the total PSQI score compared to the healthy control group (p < 0.05). According to the results of spearman's analysis, there was a significantly higher correlation between the generalised pain, fatigue, depressive symptoms, functional status, and physical score of the SF-36 and the sleep disturbance (p < 0.01). There was also a significantly lower correlation between the menopause status, dyspnoea, gastroesophageal reflux, dysphagia, the mental score of the SF-36, and the sleep disturbance (p < 0.05). The sleep quality is disturbed in patients with SSc. The lower quality of sleep is especially associated with the pain, fatigue, depressive symptoms, and functional status.