Higher prevalence of restless legs syndrome/Willis-Ekbom disease in multiple sclerosis patients is related to spinal cord lesions.

BACKGROUND: Multiple sclerosis (MS) is connected with higher prevalence of secondary restless legs syndrome/Willis-Ekbom disease (RLS/WED). Aim of this study was to determine risk factor for developing symptoms of RLS in MS patients.

METHODS: In cross-sectional study we examined 200 random MS patients. After obtaining informed consents, patients undervent a structured interview based on RLS and MS symptoms and characteristics, demographic, and health-related data. Than we collected results of brain/spinal cord magnetic resonance imaging (MRI). Blood samples were examined for blood count and biochemistry.

RESULTS: From all 200 subjects, 26% were RLS-positives (95% CI: 20-32%). From positive patients, 44% had negative family history for RLS, and developed secondary RLS after onset of MS. Compared to RLS-negatives, the positives had significantly higher prevalence of spinal cord lesions (p=0.01). Presence of spinal pathology was connected with higher risk of RLS development (OR=3.846, 95%CI:1.304-11.346). There were no statistically significant differences in the levels of red blood cells, iron metabolism parameters, or levels of B or D vitamins.

CONCLUSION: Risk of RLS/WED in MS increases with presence of lesions in spinal cord. The role of decreased dopamine delivery to lower spinal regions as the pathological background must be proved by more detailed research.