Correlation of sleep quality with fatigue and disease activity among patients with primary Sjögren’s syndrome: a cross-sectional study

ABSTRACT BACKGROUND: Fatigue is a frequent symptom in patients with primary Sjögren’s syndrome (pSS) and can be a cause of or be associated with sleep disorders. OBJECTIVE: To assess the sleep quality of pSS patients and its relationship with fatigue and disease activity. DESIGN AND SETTING: Analytical observational study conducted at an exercise psychobiology laboratory. METHODS: Sleep quality was evaluated using the Pittsburg sleep quality index (PSQI) and actigraphy. Fatigue was evaluated through the Profile of Fatigue and Discomfort - Sicca Symptoms Inventory (PROFAD-SSI-SF) and a visual analogue scale for fatigue (VAS-fatigue). Disease activity was evaluated using a visual analogue scale for pain (VAS-pain), EULAR Sjögren’s Syndrome Patient Reported Index (ESSPRI) and Disease Activity Index (ESSDAI). We summarized the data through descriptive statistics. RESULTS: A total of 50 female patients with pSS, of average age 56.4 years, were included in the study; 80% presented low disease activity. The total PSQI score showed that 74% had poor sleep. The actigraphy showed mean sleep latency of 26.2 minutes and mean nightly awakening of 48.2 minutes (duration of wakings after sleep onset, WASO). There were correlations between PSQI and VAS-pain, VAS-fatigue, PROFAD-SSI and ESSPRI. Actigraphy showed a correlation between the duration of WASO and ESSDAI. CONCLUSION: The present study provides important information regarding correlations between sleep disorders and disease activity. There is a need for proper control over disease activity and for development of strategies to help patients to sleep better in order to diminish their fatigue.【研究背景】疲劳是原发性干燥综合征（primary Sjögren’s syndrome, pSS）患者的常见症状，可诱发睡眠障碍或与之相关联。【研究目的】评估原发性干燥综合征患者的睡眠质量，及其与疲劳和疾病活动度的关联。【研究设计与场景】本研究为分析性观察研究，于运动心理生理学实验室开展。【研究方法】采用匹兹堡睡眠质量指数（Pittsburg sleep quality index, PSQI）与体动记录仪评估睡眠质量；通过疲劳与不适概况-干燥症状量表简版（PROFAD-SSI-SF）以及疲劳视觉模拟评分（VAS-fatigue）评估疲劳程度；采用疼痛视觉模拟评分（VAS-pain）、欧洲抗风湿病联盟干燥综合征患者报告结局指数（ESSPRI）以及欧洲抗风湿病联盟干燥综合征疾病活动指数（ESSDAI）评估疾病活动度。本研究通过描述性统计对数据进行汇总分析。【研究结果】本研究共纳入50名原发性干燥综合征女性患者，平均年龄为56.4岁；其中80%的患者疾病活动度较低。总PSQI评分结果显示，74%的患者存在睡眠质量不佳的情况。体动记录仪检测结果显示，平均睡眠潜伏期为26.2分钟，平均夜间觉醒时长为48.2分钟（即睡眠起始后觉醒时长，WASO）。PSQI评分与VAS-pain、VAS-fatigue、PROFAD-SSI以及ESSPRI均存在相关性。体动记录仪检测结果显示，睡眠起始后觉醒时长与ESSDAI存在相关性。【研究结论】本研究为明确睡眠障碍与疾病活动度之间的关联提供了重要参考。临床亟需合理管控疾病活动度，并制定相关策略以改善患者睡眠质量，进而缓解其疲劳症状。