Magnesium citrate monotherapy improves restless legs syndrome symptoms and multiple suggested immobilization test scores in an open-label pilot study

Abstract

Study Objectives: An estimated 3% of the population has clinically significant restless legs syndrome. Given the limited pharmacological options in the arsenal, there is a need for a therapeutic agent with a better side effect profile. Methods: Twelve treatment naive adults (10 women and 2 men with a median age of 41.5 [32–48.5] years) with primary restless legs syndrome were recruited in our open-label pilot study; magnesium citrate 200 mg was administered daily for 8 weeks. Serum magnesium levels, International Restless Legs Syndrome Study Group Rating Scale, Kohnen quality of life scale, and multiple suggested immobilization tests (three 1-hour tests) were performed before and after supplementation. Paired t tests and Wilcoxon signed-rank tests were used for data analysis. Pearson and Spearman’s analyses assessed the association between magnesium levels and restless legs syndrome variables. Results: Participants had a significant reduction in International Restless Legs Syndrome Study Group Rating Scale scores (6.67 [2.33–11] P = .006) and improved Kohnen quality of life scores (8.5 [2.09–14], P = .014) without notable differences in serum magnesium levels (P = .3). The median periodic limb movements during wakefulness index (30.40 [5.20, 122.40] to 8.63 [0.32, 17.47] P = .043) and self-reported discomfort score (19 [14, 30.5] to 6 [0, 8] P = .0010) of all 3 multiple suggested immobilization test trials also demonstrated improvement. Serum magnesium levels negatively correlated with multiple suggested immobilization test self-reported scores and the periodic limb movements during wakefulness indices. Conclusions: Despite the limitations of open-label design, our study’s positive results indicate the need for a placebo-controlled trial with a larger sample size.