A study on factors related to sleep disorders and serum BDNF expression levels in patients with primary Sjӧgren's syndrome.

Objectives: We aimed to assess the sleep quality of patients with primary Sjögren's syndrome (pSS) and the associated factors. Moreover, Preliminary exploration of the clinical significance of serum brain-derived neurotrophic factor (BDNF) in pSS patients with sleep disorders.

Methods: A self-report survey was administered to 111 pSS patients and 40 healthy individuals using the Pittsburgh Sleep Quality Index (PSQI) for sleep quality. General clinical information,the sleep quality and mental conditions were collected using on-site questionnaires and various scales. 40 healthy controls from the health examination center of the same hospital, who were age and sex matched. Detection of serum BDNF levels by ELISA method . Independent samples t tests, Chi-square analysis, logistic regression were used to analyze these data.

Results: Patients with pSS had higher scores on the PSQI than the healthy individuals. Abnormal sweating, high PHQ-9 and ESSPRI scores were independent risk factors for sleep disorders. pSS patients had lower serum BDNF than the healthy individuals, The area under the curve (AUC) of predicting sleep disorder in pSS patients using detection of serum BDNF level was 0.8470, and the sensitivity and specificity were 0.951 and 0.727, which were superior to PHQ-9 and GAD-7.

Conclusion: Compared with the healthy individuals, pSS patients had a higher prevalence of sleep disorders and lower serum BNDF. Serum BDNF level demonstrated greater predictive advantage for sleep disorder in pSS patients.