Sleep disorders in patients with multiple sclerosis in Spain

This study assesses the presence of sleep disturbances and their relationship with clinical and demographic variables in patients with MS, with a view to establishing correlations between the different variables and the frequency of sleep disturbances.

The Pittsburgh Sleep Quality Index (PSQI) was used to detect sleep disorders. We contacted patients treated at the MS unit and distributed a questionnaire (PSQI) to 221 patients, receiving 142 usable questionnaires between 8 and 30 September 2019.

The prevalence of patients with sleep disturbances in our study was 74.7% (73.7% in women and 76.8% in men). Therefore, sleep disorders are pervasive in patients with MS, with 3 out of 4 patients experiencing them, a higher rate than that observed in the population without the disease. The frequency of sleep disorders gradually increased in line with age. In the 2 age groups analyzed, 44-54 years and 55-68 years, the proportion of moderate and severe sleep disorders was 42.8% and 53.9%, respectively. Moderate and severe sleep disturbances were observed in 27.5%, 44.7%, and 58.3% of patients with Expanded Disability Status Scale scores of 0-3, 3-6, and >6, respectively.

Our results indicate that sleep disorders are more common in patients with MS than in other populations. Patients with secondary progressive forms of MS more frequently present sleep disturbances, while patients with primary progressive forms report them less frequently. Age and degree of disability were positively correlated with the prevalence and severity of sleep disorders in MS patients.