Sleep disturbances in patients with Sjogren syndrome

Objective: Primary Sjogren Syndrome (pSS) is a disorder characterized by dryness due to dysfunction of exocrine glands and additional non-exocrine manifestations from various organ systems. The most common non-exocrine manifestation is a fatigue defined as a general lack of energy not relieved by increased sleep. Excessive daytime sleepiness is defined as the propensity to fall asleep at a time when the individual would usually be awake and alert. One of the major causes for excessive day time sleepiness is periodic limb movement disorder association with restless legs syndrome (RLS). The aim of the present study was to evaluate sleep disturbances in patients with pSS.

Method: Seventy-seven voluntary patients (70 female, 7 male) admitted to the rheumatology clinic were included in the study. The control group consisted of eighty healthy (70 female,10 male) individuals. The study sample was asked to complete a socio-demographic form (age, gender, marital status, income level and educational status), Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), and the International RLS study group(IRLSSG) rating scale. The IRLSSG rating scale meets performance criteria for a brief, patient-completed instrument that can be used to assess RLS severity for purposes of clinical assessment, research, or therapeutic trials.

Results: The mean scores of the mental health, general health, vitality, physical function, physical role function, and emotional role function parameters of the patients were statistically significantly lower than those of healthy volunteers. On the ESS scale, the average score was found to be 7.9±2.8 in the patient group and 4.5±2.1 in the control group. The average IRLSSG rating scale score was 13.4±7.6 in the patient group and 5.4±5.2 in the control group. The total PSQI score was 7.8±3.5 in the patient group and 4,11±1.64 in the control group. There was a statistically significant difference in terms of ESS, IRLSSG rating scale and sleep quality scores. Patients with urinary incontinence (n=26) had significantly higher PSQI and sf-36 scores than did patients without urinary incontinence (n=51).

Conclusion: Prevalence of sleep disturbances appears to be increased in pSS and may be a useful therapeutic target to improve the quality of sleep in these patients. The effects of pSS treatment on sleep quality were not assessed due to the cross-sectional nature of the study. Further studies, where pSS patients should be followedup for an extended period of time and evaluated by polysomnography, are required.