A Survey on Sleep Disorders and Related Hormones in Patients with Newly Diagnosed Systemic Lupus Erythematosus

BACKGROUND AND OBJECTIVES: Systemic lupus erythematosus (SLE) is reportedly associated with sleep disorders. Thus, the present study aimed to investigate sleep disorders in newly diagnosed SLE patients. MATERIALS AND METHODS: This study was conducted on patients with newly diagnosed SLE (ie, case group) and a control group. The case and control groups were matched in terms of gender, age, socioeconomic status, and educational level. Venous blood samples were obtained from the participants to measure prolactin and melatonin levels. Furthermore, they were subjected to polysomnography. The data were analysed by SPSS (version 16) at a significance level of 0.05. RESULTS: A total of 28 women were enrolled in this study (ie, 14 individuals in each group). The frequencies of sleep disorder in the case and control groups were obtained as 64.3% and 50%, respectively (P=0.4). These two groups had the mean sleep onset times of 10.76±10.64 and 8.67±7.12 min (P=0.5) and the respiratory disturbance indices of 9.20±10.23 and 8.44±9.27, respectively (P=0.8). The frequency of sleep apnoea was obtained at 50% for both case and control groups (P=1). There was no significant difference between these groups in terms of the mean serum prolactin and melatonin levels (P=0.3 and P=0.2, respectively). Serum melatonin level showed a direct correlation with sleep latency to N1 (i.e., the first part of non-rapid eye movement in sleep) and spontaneous arousal index in the case group (P=0.02, r=0.602 and P=0.04, r=0.544, respectively). CONCLUSION: According to the findings, there was no significant difference in the frequency of sleep disorders between the healthy subjects and patients at the onset of lupus. Additionally, melatonin and prolactin levels showed no significant difference between the groups. Our results are inconsistent with previous studies, due to the difference in disease duration probably. It seems that the chronicity and complications of the disease, as well as the adoption of glucocorticoid therapy for the chronic disease affect sleep quality in SLE patients more than disease duration.