Iron supplementation for restless legs syndrome - A systematic review and meta-analysis
European journal of internal medicine. 2019
BACKGROUND Iron supplementation, is recommended for the treatment of restless legs syndrome (RLS). We gathered evidence for the efficacy and safety of iron supplementation for RLS. METHODS A systematic review and meta-analysis of randomized controlled trials that compared iron supplementation versus no iron for patients with RLS was performed. Multiple databases were searched. The primary outcome was the effect of iron on the International Restless Legs Syndrome score (IRLSS) at 4weeks after treatment. For dichotomous data, risk ratios (RR) with 95% confidence intervals (CIs) were estimated and pooled. For continuous data, weighted mean differences (WMD) were calculated. RESULTS Ten trials fulfilled the inclusion criteria. Iron therapy was associated with a significant decrease of the IRLSS of -3.55 [95% CI (-5.41) - (-1.68)] points and an increase in the percentage of patients with improvement of the IRLSS score, RR of 2.16 [95% CI 1.56-2.98]. IV FCM was associated with improvement in both the IRLSS (WMD of -2.79 (95% CI (-4.62) - (-0.96), 4 trials, I(2)=0%) and on the RLS-QOL by WMD of 8.67 (95% CI 1.68-15). Iron was associated with an increased rate of adverse events RR 2.04 (95% CI 1.46-2.85), which were not severe and not associated with increased rate of treatment discontinuation. CONCLUSION Iron supplementation is associated with improvement of the IRLSS score. Our meta-analysis supports the use of iron, oral or IV, as effective therapy for patients with RLS. Further studies should assess subgroups of patients most likely to benefit from iron supplementation.
Efficacy and tolerability of intravenous iron for patients with restless legs syndrome: evidence from randomized trials and observational studies
Sleep medicine. 2019
OBJECTIVE Restless legs syndrome (RLS) is a common neurological disorder of unclear pathophysiology that appears to involve an iron deficiency in the brain. Some studies, but not others, suggest that intravenous injection of iron can reduce RLS severity. METHOD The databases Web of Science, PubMed, Embase, Chinese National Knowledge Infrastructure, Wanfang, and SinoMed were searched for randomized controlled trials, cohort studies and case-control studies of intravenous iron therapy to treat RLS. Eligible studies were meta-analyzed using Stata 12.0. RESULTS This analysis indicated that IV iron was more efficacious than placebo in treating RLS (OR: 4.71,95%CI 4.21-5.21,p < 0.0001). According to sub-group analysis, either IV ferric carboxymaltose (FCM) or iron sucrose was more efficacious than placebo in treating RLS. Adverse events did not differ significantly between patients receiving intravenous iron or placebo (OR 1.68, 95%CI 0.92-3.07, p = 0.093). The present study also indicated after accepting IV iron treatment the IRLS score in RLS patients decreased (OR = 6.75,95%CI 4.02-9.49, p < 0.0001). The subgroup analysis showed that IV iron dextran, iron sucrose, and FCM could alleviate the IRLS score. CONCLUSION The available evidence suggests that intravenous iron is effective and tolerable for patients with RLS regardless of peripheral iron status.