Sleep Disturbance and Related Factors in the Patients with Relapsing-Remitting Multiple Sclerosis

Background. Sleep disturbances are commonly reported, although underestimated complaints from people with multiple sclerosis (MS). The aim of the study was to analyze the frequency and type of sleep disturbances in MS patients and to evaluate their relationships with demographics and clinical data. Methods. The study group consisted of 178 patients with relapsing-remitting MS: 130 females and 48 males. Clinical measures (disease duration, disability level in Expanded Disability Status Scale (EDSS), and treatment) were acquired from medical records. The questionnaire was applied, containing questions about sleep disturbances, somatic complaints, perception of fatigue, depression, anxiety, and problems at work and in social/family life. Athens Insomnia Scale (AIS) and Karolinska Sleepiness Scale (KSS) were performed to quantify sleep problems and Hamilton Depression Rating Scale (HDRS) and Addenbrooke's Cognitive Examination (Mini-ACE) to assess level of depression and cognitive performance. Electroencephalography was recorded to identify electrophysiological indices of sleep. Results. 109 patients (61%) reported sleep disturbances, most frequently insomnia, snoring, and parasomnias. This subgroup had significantly higher scores in AIS (p<0.0001) and KSS (p=0.010) and slightly higher EDSS score (p=0.048) and more often complained of fatigue (71% vs. 53%, p=0.0148), involuntary limb movement (42% vs. 25, p=0.0170), and breathing disturbances (10% vs. 0%). There was a significant correlation between the results of AIS and HDRS (Rs=0.715, p<0.05). Conclusion. Sleep disturbances, predominantly insomnia, are reported by more than a half of the patients with relapsing-remitting MS. Significant associations were found between sleep problems and MS-related clinical symptoms and psychosocial issues.