Determination of relationship between vitamin D level and sleep disorders in MS patients

Abstract

Multiple sclerosis (MS) is a chronic and progressive disease of the central nervous system characterized by chronic inflammation, myelin degradation of nerve cells by the immune system, and the formation of plaques in the nervous system. Sleep disorders are one of the major issues for patients with MS, but usually, it gets neglected. Materials and methods In a cross-sectional study, we selected the patients with expanded disability status scale (EDSS)<4 (early stages of MS). After determining the level of vitamin D in the blood sample of patients, the validated Persian versions of Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), and STOP-Bang questionnaires were filled by patients. Sleep conditions were described and compared between groups of patients based on mentioned factors. Also, the impact of age, disease duration and EDSS on sleep status were determined. Results This study was designed to evaluate the quality of sleep, insomnia and the risk of obstructive sleep apnea in a sample of MS patients with mild disability. According to our assessment 37.87% of MS patients had poor sleep quality. Also, a rate of 10.67% clinical Insomnia with moderate severity and 1.94% of severe insomnia, was observed in our sample. In terms of obstructive sleep apnea (OSA), only 1.94% of our sample had a high risk of OSA. We couldn't detect a considerable effect of vitamin D in none of three indices. The second result of the study was that there was a significant difference between the two groups of patients on the ease of vitamin D levels and the rate of depression on the ease of BDI (p=0.02). There was a significant relation between BDI score and ISI and PSQI scores (p<0.01), but severity of the disease, age, disease duration, and BMI didn't affect the sleep indices.