Effects of Melatonin on Sleep Quality and Disease Activity in Patients With Rheumatoid Arthritis

Background and Objective In rheumatoid arthritis (RA) patients sleep disturbance is one of serious and prevalent problems. Considering the known effects of melatonin on sleep quality and inflammation, this study aimed to investigate melatonin supplementation effect on quality of sleep and disease activity in patients with RA.Methods In this randomized, placebo-controlled trial (double-blind), 64 RA patients were selected and divided into experimental and placebo groups randomly; experimental group received 3 mg/d of melatonin and another group consumed placebo for 60 days. Before and after the investigation, assessment of the quality of sleep determined using the Pittsburgh Sleep Quality Index (PSQI). Disease Activity Score-28 (DAS28) and the Visual Analogue Scale (VAS) questionnaires were used for evaluation of disease activity and pain intensity, respectively.Results Melatonin significantly reduced PSQI, DAS28 and VAS scores, when values compared with baseline. In contrast to placebo group, good sleep quality within the melatonin group increased significantly compared to baseline and this improvement in sleep quality was significant when compared between groups. The scores of DAS28 and pain VAS at the end of trial were significantly reduced compared to the baseline in both groups. However, reduction in the DAS28 and VAS scores of the melatonin group were stronger than reductions in the placebo receiving group.Conclusions This study results revealed that melatonin was safe and effective in improving sleep quality and reducing DAS28 and pain VAS scores in RA patients.