Cognitive Impairment in Multiple Sclerosis: the Role of Sleep Disorders

Cognitive impairment is a frequent complication in multiple sclerosis (MS) and has been shown to impact the lives of MS patients to a similar extent as the physical impairments. Proper sleep is important for memory consolidation and sleep deprivation has been related to impair functioning in various cognitive domains. This study was executed upon 122 non-severely depressed MS patients and 122 age and sex-matched control volunteers who underwent assessment of their cognitive performance using the Arabic version of the Brief International Cognitive Assessment for Multiple Sclerosis (BICAMS). In addition, sleep health was assessed by sleep quality scale, Epworth sleepiness scale, and Pittsburg sleep quality index (PSQI). Impaired cognitive performance was found in 45.9% of MS patients and its impact was noted in all aspects of BICAMS. The mean of PSQI was 14.82 ± 4.3. Higher PSQI scores and Epworth sleep scale score significantly increase the risk of cognitive impairment among MS patients by 1.548 and 1.355 folds, respectively. Sleep quality impairment may help predict cognitive decline in MS patients. Results highlight the need to assess sleep into routine MS care. Effective management of sleep disturbance may offer a promise for improving cognitive dysfunction in MS.