Mehmood Tahir, Auerbach Michael, Earley Christopher J, Allen Richard P
Division of Transfusion Medicine, Department Laboratory Medicine and Pathology, Mayo Clinic, Rochester, MN, USA.
Department of Medicine, Georgetown University, Washington DC, USA; Private Practice, Baltimore, MD, USA.
Sleep Med. 2014 Dec;15(12):1473-6. doi: 10.1016/j.sleep.2014.08.012. Epub 2014 Sep 10.
Iron deficiency anemia (IDA) engenders restless legs syndrome (RLS, aka Willis-Ekbom disease). Intravenous (IV) iron can rapidly reverse IDA and would be expected to similarly reverse RLS caused by IDA. This is the first consecutive case series evaluating the effects of IV iron therapy on RLS occurring with IDA (RLS-IDA).
RLS-IDA patients were evaluated before and 7-12 months after a 1000-mg IV infusion of low-molecular-weight iron dextran (INFeD(@)) using validated questionnaires and standardized telephone interview. Patients were classified as respondent versus nonrespondent for RLS improvement.
Follow-up data were obtained on 42 (70%) of 60 consecutive RLS-IDA patients. The symptoms of RLS were reduced in 76% (32/42) with 47% (20/42) showing an extended response lasting >6 months. The response did not relate to age or gender, but tended to be less among African-Americans than Whites (40% (2/5) vs. 81% (30/37), p = 0.078). White respondents versus nonrespondents had higher hemoglobin levels after treatment (12.1 vs. 11.3 g/dl, p = 0.03).
RLS-IDA is reduced after administration of IV iron in most cases, but the 24% failing to respond was higher than expected. The nonrespondents all showed below-normal hemoglobin levels (<12.5 g/dl) suggesting a failure of adequate treatment of the iron deficiency. IV iron treatment of the RLS with IDA likely requires ensuring more than minimally adequate body iron stores to support iron delivery to the brain. For some, this may require a dose higher than the customary 1000-mg IV iron used for the treatment of either IDA or RLS alone.
缺铁性贫血（IDA）可引发不宁腿综合征（RLS，又称威利斯-埃克博姆病）。静脉注射铁剂可迅速纠正IDA，预计同样能纠正由IDA引起的RLS。这是首个连续病例系列研究，评估静脉注射铁剂治疗伴发于IDA的RLS（RLS-IDA）的效果。
采用经过验证的问卷和标准化电话访谈，对接受1000毫克低分子右旋糖酐铁（INFeD®）静脉输注前及输注后7至12个月的RLS-IDA患者进行评估。根据RLS改善情况，将患者分为有反应者和无反应者。
在连续60例RLS-IDA患者中，获得了42例（70%）的随访数据。76%（32/42）的患者RLS症状减轻，其中47%（20/42）表现出持续超过6个月的延长反应。反应与年龄或性别无关，但非裔美国人的反应率往往低于白人（40%（2/5）对81%（30/37），p = 0.078）。有反应的白人患者与无反应的白人患者相比，治疗后血红蛋白水平更高（12.1对11.3 g/dl，p = 0.03）。
多数情况下，静脉注射铁剂后RLS-IDA症状减轻，但24%无反应的比例高于预期。无反应者的血红蛋白水平均低于正常（<12.5 g/dl），提示缺铁未得到充分治疗。静脉注射铁剂治疗伴IDA的RLS可能需要确保体内铁储备超过最低充足水平，以支持铁向大脑的输送。对某些患者而言，这可能需要高于常规用于单独治疗IDA或RLS的1000毫克静脉注射铁剂的剂量。
