Sleep disturbances in multiple sclerosis

Objectives: The frequency of sleep disturbances in multiple sclerosis (MS), and their impact on the quality of life of MS patients, have traditionally been underestimated. Here we review the most common sleep disorders seen in this disease, their prevalence, pathophysiology, clinical manifestations and current treatments. Method: We begin with a brief description of epidemiological data on sleep disturbances in MS, explain how these disturbances increase potential associated morbidities, and discuss the bidirectional relationship established between these two comorbid conditions (i.e. MS worsens sleep disturbances and vice versa). We then analyze the main dyssomnias and parasomnias described in MS: insomnia, circadian rhythm disorders, drug-induced sleep disturbances, restless legs syndrome (RLS) and periodic leg movements (PLM), respiratory disorders during sleep, narcolepsy-cataplexy syndrome and REM sleep behavior disorder (RBD). We also review the relationship between sleep disturbances and chronic fatigue syndrome, which is very frequent in MS patients. Conclusion: Sleep disturbances are more common in MS patients than in the general population and limit these patients' quality of life. Therefore, we believe that these disturbances should be a focal point in any multidisciplinary treatment for MS. (C) 2011 Elsevier B.V. All rights reserved.