A randomized, double-blind, placebo-controlled trial of intravenous iron sucrose in restless legs syndrome. A randomized, double-blind, placebo controlled, multi-center study of intravenous iron sucrose and placebo in the treatment of restless legs syndrome. A double-blind, placebo-controlled trial of intravenous iron dextran therapy in patients with ESRD and restless legs syndrome. Efficacy of oral iron in patients with restless legs syndrome and a low-normal ferritin: A randomized, double-blind, placebo-controlled study. Iron therapy in the pediatric hemodialysis population.
The aim of this study was to ascertain whether high-dose intravenous (IV) iron sucrose could improve symptoms and change brain iron concentrations in idiopathic RLS.
                The study was a randomized, parallel-group double-blind study of 1000mg iron sucrose given IV versus placebo. Primary measures of the clinical status were global rating scale (GRS) and periodic leg movements of sleep (PLMS). Primary measures of brain iron status were CSF ferritin and MRI-determined iron in the substantia nigra.
                At the time of the interim analysis there were 7 placebo and 11 iron-treated subjects. At 2-weeks post-treatment, iron treatment resulted in a small but significant increase in CSF ferritin and a decrease in RLS severity (GRS) but did not change PLMS or MRI iron index. None of the secondary outcomes changed with treatment. There was no single case of clear treatment benefit in any of the patients. This interim analysis revealed an effect size that was too small to allow for adequate power to find significant differences with the planed 36-subject enrollment for either the primary objective outcome of PLMS or any of the secondary outcomes. The study was stopped at this planned break-point given the lack of both adequate power and any indication for clinically significant benefit.
                High-dose IV iron failed to demonstrate the robust changes reported in three prior open-label studies. Differences in iron formulation, dosing regiment, and peripheral iron status may explain some of the discrepancies between this and previous IV iron treatment studies. Iron deficiency may exacerbate symptoms in the Restless Legs Syndrome (RLS). We investigated the effect of intravenous iron sucrose or placebo on symptoms in patients with RLS and mild to moderate iron deficit. Sixty patients with primary RLS (seven males, age 46 (9) years, S-ferritin < or =45 microg/L) recruited from a cohort of 231 patients were randomly assigned in a 12-months double-blind, multi-centre study of iron sucrose 1000 mg (n = 29) or saline (n = 31). The primary efficacy variable was the RLS severity scale (IRLS) score at week 11. Median IRLS score decreased from 24 to 7 (week 11) after iron sucrose and from 26 to 17 after placebo (P = 0.123, N.S. for between treatment comparison). The corresponding scores at week 7 were 12 and 20 in the two groups (P = 0.017). Drop out rate because of lack of efficacy at 12 months was 19/31 after placebo and 5/29 patients after iron sucrose (Kaplan-Meier estimate, log rank test P = 0.0006) suggesting an iron induced superior long term RLS symptom control. Iron sucrose was well tolerated. This study showed a lack of superiority of iron sucrose at 11 weeks but found evidence that iron sucrose reduced RLS symptoms both in the acute phase (7 weeks) and during long-term follow up in patients with variable degree of iron deficiency. Further studies on target patient groups, dosing and dosing intervals are warranted before iron sucrose could be considered for treatment of iron deficient patients with RLS.
                Copyright 2009 Movement Disorder Society. Restless legs syndrome (RLS) is a common disorder in patients with end-stage renal disease (ESRD) that causes motor agitation and insomnia. Because RLS has been associated with iron deficiency, we sought to investigate the effects of intravenous (IV) iron dextran on symptoms of RLS in a double-blind placebo-controlled trial.
                Patients determined to have RLS by International RLS Study Group criteria were administered either iron dextran, 1,000 mg, or normal saline IV in a blinded fashion. Patient demographic data were collected, and blood chemistry tests, liver function studies, serum iron levels, ferritin levels, and total iron-binding capacity were obtained at baseline and 1, 2, and 4 weeks postinfusion. Side effects or adverse events to interventions were monitored, and RLS symptoms were assessed by a rating scale at the same intervals.
                Eleven patients were randomly assigned to the administration of iron dextran, and 14 patients to the administration of saline. RLS severity scores were slightly higher in the placebo group at baseline, but hemoglobin levels, iron stores, and other biochemical parameters did not differ. Although no change in symptoms were seen in the placebo-treated group, significant improvement in RLS symptom scores in response to iron dextran was seen 1 week after infusion (-2; interquartile range [IQR], -6 to -1; P = 0.03, Wilcoxon's rank sums), but was greatest at 2 weeks (-3; IQR, -5 to -2 compared with -1 to 0; P = 0.01). Salutary effects of iron persisted at 4 weeks, but were no longer statistically significant. The significant increase in serum ferritin levels and iron saturation observed in the iron dextran-treated group was not seen in the placebo-treated group. No differences in adverse events were noted between groups.
                High-dose iron dextran infusion is associated with a significant, but transient, reduction in symptoms of RLS in patients with ESRD. Restless Legs Syndrome (RLS) is a primary disorder of sensation that affects sleep and has been associated with iron deficiency. The purpose of this study was to determine if symptomatic RLS patients with low-normal serum ferritin levels benefit from oral iron replacement.
                This was a randomized, placebo-controlled, double-blinded study. Eligible patients were randomized to oral iron therapy vs. appearance-matched placebo and followed over a 12 week period.
                Baseline International Restless Leg Scale (IRLS) scores for the treatment (24.8+/-5.72) and placebo (23.0+/-5.03) groups were similar. Baseline ferritin levels for the treatment (40.6+/-15.3ng/ml) and placebo (36.7+/-20.8ng/ml) groups were also similar. After 12 weeks, IRLS scores decreased more in the treatment arm (10.3+/-7.40) than in the placebo arm (1.14+/-5.64), (p=0.01). Ferritin levels increased more in the treatment arm (25.1+/-20.3ng/ml) than in the placebo arm (7.5+/-13.7ng/ml), (p=0.04). We observed a nonsignificant trend toward improved quality of life in the treated patients, (p=0.07).
                This is the first double-blinded, placebo-controlled study to demonstrate statistically significant improvement in RLS symptoms using oral iron therapy in patients with low-normal ferritin. The findings from this study suggest that additional larger randomized placebo-controlled trials of iron as treatment for patients with low-normal ferritin are warranted. Iron therapy maintains iron stores and optimizes the response to recombinant human erythropoietin (r-HuEPO) in patients with end-stage renal failure. Information is limited, however, regarding the preferential route of iron administration in pediatric patients receiving hemodialysis. Therefore, we prospectively randomized 35 iron-replete patients (aged >1 to <20 years) to receive up to 16 weeks of maintenance i.v. ( n=17) or daily oral ( n=18) iron. Eligible patients had received hemodialysis for >2 months, had a baseline transferrin saturation [TSAT] >20%, and were receiving maintenance r-HuEPO. Treatment arms were evenly distributed with respect to baseline demographic and clinical characteristics, with no statistically significant differences in baseline hemoglobin (Hb), hematocrit (Hct), reticulocyte Hb content (CHr), serum ferritin (SF), TSAT, or r-HuEPO dose. In the 35 patients, i.v. iron dextran and not oral iron was associated with a significant increase (138.5 to 259.1 ng/ml, P=0.003) in SF. A comparison of the change in SF between the i.v. iron group and the oral iron group was also significant ( P=0.001). Whereas only i.v. iron was associated with a significant decrease in the dose of r-HuEPO (234.0 to 157.6 U/kg per week, P=0.046) and an increase of the CHr (29.2 to 30.1 pg, P=0.049), these changes were not significantly different from those experienced by patients in the oral iron group. In both groups, the Hct remained stable and in neither group was there a significant change in the TSAT. In summary, although both oral and i.v. iron maintained patients in an iron-replete state in this short-term study, only i.v. therapy allowed for a significant improvement in iron stores.
There is insufficient evidence to determine whether iron therapy is beneficial for the treatment of RLS. Further research to determine whether some or all types of RLS patients may benefit from iron therapy, as well as the best route of iron administration, is needed.