RLS and blood donation

Background and purposeThe link between brain iron deficiency and RLS is now well established. In a related observation, several conditions that can deplete iron stores have been linked to increased probability of RLS. Blood donation has been linked to iron deficiency. It has thus been hypothesized that donating blood may be a risk factor for developing RLS.Patients and methodsTwo thousand and five UK blood donors, ranging from first-time donors to some who had donated more than 70 times, completed the validated Cambridge-Hopkins RLS questionnaire (CH-RLSq) following their donation session. The questionnaire included a set of questions designed to diagnose RLS. The donors’ histories of blood donations were determined both from self-report and from the National Blood Service database.ResultsA number of statistical models were constructed to determine whether the probability of RLS diagnosis was related to the history of blood donations. Controlling for age and sex, no evidence was found to suggest that a greater number or frequency of blood donations increased the risk of RLS. Even amongst sub-groups especially vulnerable to iron depletion through blood donation, such as vegetarians or low weight individuals, no evidence for an increased risk of RLS could be found.ConclusionsWe found no evidence that the frequency or number of blood donations up to the UK maximum of three times a year would increase the risk of RLS.     

No association between plasma hepcidin levels and restless legs syndrome - results from the Danish Blood Donor Study

BackgroundRestless Legs Syndrome (RLS) is a neurological sensorimotor disorder that occurs in the evening and night, thereby often impacting quality of sleep in sufferers. The aetiology of RLS is not completely understood although iron dysregulation has been suggested as a likely pathway. The relationship between RLS and the iron regulatory protein hepcidin has not been studied in large cohorts. We aimed to assess whether an association between plasma hepcidin variation and RLS exists in a large cohort of healthy individuals.MethodsPlasma hepcidin levels were measured in 9708 Danish blood donors from the Danish Blood Donor Study all of whom correctly completed the validated Cambridge–Hopkins RLS-questionnaire for RLS assessment.ResultsA total of 466 blood donors were determined as current RLS cases in the sample (4.8%). RLS cases had a significantly higher proportion of females (56.7% vs 46.7%; P < 0.001) and were older (median age [IQR] 40.6 years vs 38.0 years; P = 0.010) than controls. RLS cases were also more frequent smokers (P = 0.004). No significant differences were found in body mass index (BMI), alcohol consumption, time of donation and donation history between cases and controls. No difference in plasma hepcidin levels was observed between RLS cases and controls (median concentration [IQR]: 10.5 ng/ml [6.3–16.4] in RLS cases vs 10.5 ng/ml [6.0–16.5] in controls). Using a logistic regression model, we found that hepcidin levels were not associated with RLS after adjusting for age, sex, alcohol consumption, smoking status, donation time and donation history (OR = 1.00 [0.99–1.02] per 1 ng/ml increase of hepcidin; P = 0.429).ConclusionOur study in Danish blood donors did not find an association between RLS and plasma hepcidin levels. Our findings suggest that plasma hepcidin's role as a potential diagnostic biomarker of RLS is inadequate.     

Épidémiologie du syndrome des jambes sans repos

IntroductionRestless legs syndrome (RLS) is a chronic sensorimotor disorder where patients complain of an almost irresistible urge to move their legs. This urge can often be accompanied by pain or other unpleasant sensations, it either occurs or worsens with rest particularly at night, and improves with activity. The International Restless Legs Syndrome Study Group has established four essential criteria for clinical diagnosis of RLS.State of artAffecting an estimated 7.2 to 11.5% of the adult population, the symptoms of RLS may be associated with significant sleep disturbance and may have a negative impact on quality of life. The prevalence of RLS increases with age, and women are more frequently affected than men. In France, the estimated prevalence is 8.5%. Among sufferers, 4.4% complain of very severe symptoms. Although RLS is mainly idiopathic, several clinical conditions have been associated with it, especially iron deficiency with or without anemia, end-stage renal disease and pregnancy. These conditions may share a common pathophysiological mechanism involving a disorder of iron metabolism. By contrast, controversy persists as to whether polyneuropathy, particularly when associated with diabetes, is to be considered as an important cause of secondary RLS. This association is difficult to demonstrate as conventional electromyography is not adequate to detect small fiber neuropathy often associated with diabetes.Conclusion and perspectivesRLS is often underdiagnosed and few subjects receive recommended RLS drug treatment. There is a clear need for complementary education to improve the accurate diagnosis of RLS. Indeed, better knowledge of this syndrome is a prerequisite to prompt an appropriate therapeutic management.     

Is preeclampsia associated with restless legs syndrome?

ObjectiveRestless legs syndrome (RLS) is a common neurologic disorder. Secondary RLS includes pregnancy and iron deficiency. Prevalence of RLS in pregnancy ranges from 11% to 27%. We aimed to assess the frequency and characteristics of RLS in pregnancy in a Peruvian population and to evaluate the possible pregnancy or delivery complications due to RLS.MethodsWe assessed 218 consecutive expectant mothers at the inpatient clinic of the Hospital San Bartolome in Lima, Peru. Assessment was performed by using the standard diagnostic criteria for RLS and by using a clinical and diagnostic interview. Questionnaires for RLS severity, idiopathic RLS (IRLS), and excessive daytime sleepiness (EDS) according to the Epworth sleepiness scale (ESS) were used. Blood examination was performed for hemoglobin and hematocrit. For comparison, RLS patients were matched for age and body mass index (BMI) with pregnant women without RLS.ResultsOut of 218 patients, 40 (18.4%) fulfilled diagnostic criteria for RLS. In RLS patients, prophylactic iron supplementation therapy during pregnancy was less frequently taken (P = .02). Pregnant women with RLS had a higher ESS score than pregnant controls (10.6 +/− 3.1 vs 7.6. +/− 3.6; P < .001). Preeclampsia was more frequent in RLS (7/40 vs 1/39; P = .03).ConclusionsIn our study, RLS was frequent in pregnant Peruvian women, especially in those without prophylactic iron supplementation. RLS patients described more EDS. Preeclampsia was more common in RLS. Our study is the first study to indicate a possible association between RLS and preeclampsia.     

Restless legs syndrome in blood donors

BACKGROUND AND PURPOSE: Restless legs syndrome (RLS) may be a cause of significant sleep disturbance. In a Swedish survey, the prevalence of RLS has been estimated to be 5.8% among men and 11.4% among women. Blood donation may result in iron deficiency, which is hypothesized to be one substantial cause of RLS. PATIENTS AND METHODS: Nine hundred and forty-six (618 men, 328 women) consecutive blood donors aged 18-64 years, who attended a blood donation unit in mid-Sweden, answered a questionnaire that included questions about sleep habits. Frequency of blood donation was recorded and intake of iron tablets was assessed. Red blood cell distribution width (RDW) was also recorded. The value of RDW increases in relation to iron deficiency. RESULTS: RLS affected 14.7% of male and 24.7% of female blood donors. The mean intake of iron among the blood donors after each blood donation was only 781 mg, although the recommended intake is 2000 mg. Among the women, 7.4% presented an RDW of >14.5%, which strongly indicates iron deficiency. In this group of women, 37.5% were affected by RLS. The female RLS-sufferers were more affected than the female non-RLS subjects by problems initiating sleep (P=0.006 maintaining sleep (P<0.0001) and were also less refreshed upon awakening (P<0.001). RESULTS: This study showed that RLS was common among female blood donors. Women with RLS were more iron-deficient than those without and were affected by impaired sleep.     

Restless legs syndrome is a common feature of adult celiac disease

Restless legs syndrome (RLS) is a common neurological condition, frequently idiopathic, sometimes associated with specific disorders such as iron deficiency. We investigated RLS prevalence in celiac disease (CD), an autoimmune disease characterized by several features such as malabsorption‐related iron deficiency anemia and peripheral neuropathy. We screened a population of 100 adult CD patients for CD features, iron metabolism, clinical and neurological conditions, and enrolled 100 age‐ and sex‐matched controls in the general population. RLS was ascertained in CD patients and controls by both the presence of the four essential International RLS Study Group diagnostic criteria and neurological examination. The International RLS Study Group rating scale was used to measure RLS severity. We found a 31% prevalence of RLS in the CD population that was significantly higher than the prevalence in the control population (4%; P < 0.001). The average severity of RLS in CD population was moderate (17 ± 6.5). In the CD population, no significant correlation was found between RLS and either gluten‐free diet or iron metabolism, despite hemoglobin levels were significantly lower in CD patients with RLS than without RLS (P = 0.003). We found no correlation between RLS and other possible causes of secondary RLS, including signs of peripheral neuropathy, pregnancy, end‐stage renal disease, and pharmacological treatments.Our study broadens the spectrum of neurological disorders associated with CD and indicates that RLS should be sought for in all patients with CD. © 2010 Movement Disorder Society     

Restless legs syndrome in pregnancy is connected with iron deficiency

ObjectiveAlmost one-third of pregnant women develop symptoms of restless legs syndrome (RLS), which could have a negative impact on quality of life and the course of pregnancy and/or labor. The aim of our study was to determine possible risk factors for developing RLS in pregnant women.MethodsA total of 300 random women in the third trimester of gravidity filled out a simple questionnaire based on the official diagnostic criteria for RLS. Respondents positive for RLS were interviewed to further characterize their symptoms. The parameters of iron metabolism were examined based on blood samples. All data were statistically analyzed.ResultsWe detected significantly lower hemoglobin levels with signs of hypochromic anemia typical of iron deficiency in RLS-positive respondents, although oral iron supplementation was significantly higher in this group. The overall severity of symptoms correlated inversely with hemoglobin level.ConclusionAccording to our results, it appears that serum iron level disturbances play a crucial role in the pathophysiology of secondary RLS in pregnant women.     

Restless legs syndrome in an Indian urban population

BackgroundThe prevalence of restless legs syndrome (RLS) in India is unknown.ObjectivesThe primary objective was to assess the occurrence of RLS in residents of Bangalore. The secondary objective was to correlate demographic and socioeconomic factors with RLS occurrence and severity.MethodsThis was a cross-sectional, questionnaire-based survey conducted during August 2005 among adult residents of Bangalore, who participated in a face-to-face interview. Diagnosis of RLS was based on fulfillment of all National Institutes of Health/International Restless Legs Syndrome Study Group (NIH/IRLSSG) essential criteria. Severity of RLS was assessed using the IRLSSG scale.ResultsRLS occurred in 27 (2.1%) of 1266 respondents. Predominant symptoms included “pulling,” “tingling” and “pain”. RLS was associated with delayed sleep onset and RLS severity correlated with the duration of delay in sleep onset. RLS was associated with per-capita income less than the equivalent of US$1/day, education less than high school level, chronic daily alcohol consumption and chronic blood loss.ConclusionThis is the first Indian population study on RLS which reveals prevalence of the disorder in a South Indian urban population at 2.1%. Larger studies are warranted to better characterize RLS in India.     

Celiac disease as a possible cause for low serum ferritin in patients with restless legs syndrome

ObjectiveTo describe celiac disease (CD) as a possible cause for low serum ferritin in patients with restless legs syndrome (RLS).BackgroundLow iron stores have been found to be a risk factor for RLS with serum ferritin levels less than 45–50 ng/mL associated with increased severity of RLS. It has become routine clinical practice to test serum ferritin in the initial assessment of RLS. CD is a common genetic disorder that can cause iron deficiency.MethodsConsecutive case series of four patients with RLS and serum ferritin below 25 ng/mL, who had positive screening tests for celiac disease.ResultsWe report four patients who had serum ferritin <12 ng/mL and positive screening tests for CD. All had CD confirmed by duodenal biopsy and response to a gluten-free diet. RLS symptoms improved in all four, with two able to discontinue RLS medication and two responding without medication.ConclusionsIn patients with RLS and low serum ferritin who do not have an obvious cause for iron deficiency, we suggest looking for CD by simple, inexpensive serologic testing. Diagnosis and treatment of CD is likely to improve the outcome for RLS, as well as identify individuals who are at risk for the significant long-term complications of CD.     

Restless legs syndrome and pregnancy or delivery complications in China: a representative survey

ObjectiveTo perform a detailed epidemiological study of Chinese women and the relationship between restless legs syndrome (RLS) in pregnancy and any associated complications during delivery.MethodsA total of 3874 pregnant women (18–40 years) who had delivered babies at The First Affiliated Hospital of Zhengzhou University from May 2011 to May 2014 were enrolled in the study. Using a face-to-face interview questionnaire, data were collected pertaining to RLS incidence in pregnancy and any associated complications during delivery. The relationship between RLS frequency and pregnancy or delivery complications was further investigated.ResultsAmong 12.3% of the eligible participants, RLS prevalence occurred at least weekly. Older pregnant women were more likely to suffer from RLS. Individuals who experienced RLS at least weekly reported a statistically higher frequency of excessive daytime sleepiness and an increased prevalence of hypertension, cardiovascular disease, and preeclampsia compared with those without RLS.ConclusionThe study revealed that RLS was frequent in Chinese pregnant women, especially in those with pregnancy or delivery complications such as hypertension, cardiovascular disease, and preeclampsia. Restless legs syndrome was also associated with excessive daytime sleepiness.     

Prevalence of restless legs syndrome in blood donors

Iron deficiency anemia has been linked to restless legs syndrome (RLS) and regular blood donation may lead to iron deficiency. It has been reported that blood donations may be associated with RLS. A recent study from Sweden found that 25% of the women donors were affected by RLS. However, this type of study has not been replicated in the United States. We conducted a study in our blood donation unit between September and October 2008. To identify those with RLS, we used the RLS diagnostic index questionnaire by Benes et al. The proportion of blood donors with RLS was estimated and the number of blood donations and hemoglobin levels were compared according to RLS status. One hundred and fifty one patients were interviewed; 7 patients who donated only platelets were excluded, leaving 144 patients for analysis. There were 13 (9.0%, 95% confidence interval [CI]: 4.9–14.9%) patients with RLS. Of these, 7 (4.9%, 95% CI: 2.0–9.8%) had possible RLS and 6 (4.2%, 95% CI: 1.5–8.9%) had major or clinically relevant RLS. There was no dramatic association between RLS and number of blood donations or hemoglobin level (all P ≥ 0.21). In our sample of blood donors in the United States, the prevalence of major RLS was 4%. We could not demonstrate an association between RLS and the frequency of blood donation or hemoglobin level in our relatively small sample; a larger sample is needed to better identify any associations. © 2010 Movement Disorder Society     

SNCA-Rep1 polymorphism correlates with susceptibility and iron deficiency in restless legs syndrome

BackgroundBrain iron disequilibrium and dopaminergic dysfunction are key pathophysiological features of Restless Legs Syndrome (RLS). Rep1 polymorphism in the promotor region of SNCA is associated with risk of Parkinson's disease, however its association with RLS and iron status is unclear.ObjectiveTo investigate SNCA-Rep1 polymorphism in RLS and its phenotypes.MethodsWe recruited RLS patients as well as age and gender matched healthy controls. Demographic information and clinical features of RLS were recorded. Laboratory examinations were performed to exclude possible secondary causes.Results215 RLS patients and 369 healthy controls were included. We found that the Rep1 allele 0 homozygosity significantly decreased RLS risk (OR: 0.345; P < 0.0001, and remained significant after the Bonferroni correction). Phenotypic analysis demonstrated that longer Rep1 alleles were associated with increased susceptibility to iron deficiency (53.0% vs 36.1%, P = 0.017), however had no phenotypic significant effects on age, gender, onset age, duration, RLS family history, severity, laterality, extra body involvement and seasonal fluctuation. Multivariate logistic regression analyses confirmed long Rep1 allele was associated with higher risk of iron deficiency in RLS after adjusting for potential confounding factors. In detail, Rep1 allele 2 homozygosity was prone to a higher risk of peripheral iron deficiency in RLS (OR: 4.550, P = 0.006, remained significant after the Bonferroni correction).ConclusionThe SNCA-Rep1 variability modified RLS risk and influenced peripheral iron deficiency in this group of Chinese RLS patients. Rep1 allele 0 homozygosity decreased the risk of RLS, while homozygous allele 2 increased the risk of nonanemic iron deficiency in RLS.     

Epidemiology of restless legs syndrome: the current status

Epidemiological studies in restless legs syndrome (RLS) have often been limited by misdiagnosis and by the fact that affected individuals, even when their symptoms are severe, might not seek medical care. Some of these limitations have been overcome in the last years as population studies based on face to face interviews have been carried out with new standardized diagnostic criteria. According to these studies, and in contrast to earlier views, RLS has been shown to be a common disorder with prevalences ranging between 2.5 and 10% of the population. Although few studies performed outside Europe/North America have shown a low prevalence, a number of methodological issues have been raised that might question these results. Furthermore, once established, RLS usually follows a chronic course, and preliminary evidence shows that it might worsen over time in some patients. Endstage renal disease, increasing age, female gender, pregnancy, frequent blood donations, iron deficiency and neuropathy are considered to be risk factors for this disorder. The association to RLS is less definitely established for other conditions, such as PD or diabetes. In summary, epidemiological evidence suggests that RLS is a common neurological disorder-with high impact on many aspects of the life of those affected.     

Contrasting painless and painful phenotypes of pediatric restless legs syndrome: a twin family study

ObjectiveThis study was designed to investigate painless and painful subsets of pediatric restless legs syndrome (RLS) for genetic influence and for associations with iron deficiency and common pediatric pain disorders.MethodsIn a twin family study, twins (3–18 years) and their oldest siblings, mothers and fathers completed questionnaires, assessing lifetime prevalence of RLS using current criteria, as well as history of iron deficiency and pediatric pain disorders. Subsets were categorized as RLS-Painless or RLS-Painful. Within twin pair analyses were conducted to assess familial and potential genetic effects for the defined subsets. Penalized maximum likelihood logistic regression was used to test familial associations. Random-effects logistic regression modeling was used in the total pediatric sample to investigate univariate and multivariate associations with the subsets.ResultsData were available for 2033 twin individuals (1007 monozygous (MZ), 1026 dizygous (DZ); 51.7% female), 688 siblings, 1013 mothers and 921 fathers. Odds ratios, correlations and casewise concordance were significantly higher in MZ than in DZ twins only for RLS-Painful. RLS-Painless, though familial (co-twin and mother), was not genetically influenced, but was independently associated with female sex (OR 0.52, p = 0.003), iron deficiency (OR 4.20, p < 0.001) and with persistent pain disorders (OR 2.28, p = 0.02). RLS-Painful was familial and was probably genetically influenced; was independently associated with non-migraine headaches (OR 2.70, p = 0.02) and recurrent abdominal pain (OR 2.07, p = 0.04).ConclusionsPediatric RLS was heterogeneous and was categorized into contrasting painless and painful phenotypes. RLS-Painless was associated with iron deficiency while RLS-Painful accounted for the heritability of RLS.     

Epilepsy and restless legs syndrome

ObjectiveRestless legs syndrome (RLS) is a common neurological movement disorder occurring in approximately 10% of the general population. The prevalence of moderately severe RLS is 2.7% overall (3.7% for women and 1.7% for men). Epilepsy is also a common neurological disorder with significant associated morbidity and impact on quality of life. We evaluated the severity and frequency of primary RLS in patients with localization-related temporal lobe epilepsy (TLE) and investigated the role of prodromal RLS symptoms as a warning sign and lateralizing indicator.MethodsAll epilepsy patients seen in the outpatient clinic were screened for movement disorders from 2005 to 2015. Ninety-eight consecutive patients with localization-related TLE (50 right TLE and 48 left TLE) who met inclusion criteria were seen in the outpatient clinic. The control group consisted of 50 individuals with no history or immediate family history of epilepsy.Each patient was evaluated with the International Restless Legs Study Group (IRLSSG) questionnaire, NIH RLS diagnostic criteria, ferritin level, and comprehensive sleep screening including polysomnography. Furthermore, patients with obstructive sleep apnea or a definite cause of secondary restless legs syndrome such as low serum ferritin or serum iron levels were also excluded from the study.ResultsThere was a significant association between the type of epilepsy and whether or not patients had RLS χ² (1) = 10.17, p < .01, using the χ² Goodness of Fit Test. Based on the odds ratio, the odds of patients having RLS were 4.60 times higher if they had right temporal epilepsy than if they had left temporal epilepsy, serving as a potential lateralizing indicator. A prodromal sensation of worsening RLS occurred in some patients providing the opportunity to intervene at an earlier stage in this subgroup.SignificanceWe identified frequent moderate to severe RLS in patients with epilepsy. The frequency of RLS was much more common than would typically be seen in patients of similar age. The restlessness was typically described as moderately severe. The RLS symptoms were more common and somewhat more severe in the right TLE group than the left TLE group.     

Daytime symptoms of restless legs syndrome – clinical characteristics and rotigotine effectiveness

ObjectiveTo elucidate the prevalence and clinical characteristics of daytime restless legs syndrome (RLS) among patients with idiopathic RLS and investigate the effectiveness of rotigotine for daytime RLS.MethodsIn 256 enrolled RLS patients, we investigated factors associated with the presence of RLS symptoms throughout the day. We also assessed the duration of daytime RLS symptoms at hourly intervals, time of initial symptom onset during the day, and associations between duration of daytime and nighttime RLS symptoms. In addition, we compared changes in duration and frequency of RLS symptoms during daytime and nighttime after randomly assigning patients to a 13-week treatment with rotigotine, a dopamine agonist patch with 24-hour action, or placebo.ResultsEighty-one (31.6%) patients had daytime RLS symptoms. Only the International Restless Legs Syndrome Study Group rating scale total score was significantly associated with the presence of daytime RLS symptoms (p < 0.01) on multiple logistic regression analysis. Daytime RLS symptom onset was at 6 a.m. in 44.4% of patients; symptom duration increased significantly toward nighttime. There was a significant positive association between duration of daytime and nighttime RLS symptoms (p < 0.0001) and a greater statistically significant reduction of daytime RLS symptom duration with rotigotine treatment than with placebo (p = 0.03).ConclusionsDaytime symptoms are frequent in patients with RLS and may be associated with increased severity of the disorder and prolonged nighttime RLS symptoms. Rotigotine could become an important treatment choice for daytime symptoms.     

Síndrome de piernas inquietas en esclerosis múltiple: evaluación de factores de riesgo y repercusión clínica

IntroductionRestless legs syndrome (RLS) is a disorder characterised by an irresistible urge to move the legs, usually accompanied by unpleasant sensations. It is more frequent in patients with multiple sclerosis (MS) than in the general population.ObjectivesTo evaluate the prevalence of RLS, defined according to the 4 essential requirements included in the diagnostic criteria proposed by the International Restless Leg Syndrome Study Group, in a cohort of patients with MS; and to identify potential risk factors and the clinical impact of RLS.ResultsThe sample included 120 patients with MS, with a mean age of symptom onset of 40 years and an average disease duration of 46 months. The prevalence rate of RLS was 23.3%. MS progression time was significantly shorter in patients with RLS (P = 0.001). A recent relapse, and symptoms of anxiety, depression, and neuropathic pain were significantly associated with risk of RLS (P = 0.001, P < 0.001, P < 0.001, and P = 0.001, respectively). In addition, patients with RLS had a greater risk of poor sleep quality, fatigue, daytime sleepiness, and poor quality of life than those without RLS (P = 0.002, P = 0.017, P = 0.013, and P = 0.009, respectively).ConclusionsRLS should be considered in the neurological evaluation of patients with MS; early diagnosis and treatment would improve the quality of life of patients with MS presenting RLS.     

Bioinformatic analysis of proteomic data for iron,inflammation, and hypoxic pathways in restless legs syndrome

Objective/BackgroundWe performed bioinformatic analysis of proteomic data to identify the biomarkers of restless legs syndrome (RLS) and provide insights into the putative pathomechanisms, including iron deficiency, inflammation, and hypoxic pathways.Patients/methodsPatients with drug-naïve idiopathic RLS were recruited at a university hospital from June 2017 to February 2018. Serum samples from patients with RLS (n = 7) and healthy sex- and age-matched controls (n = 6) were evaluated by proteomic analysis. For differentially expressed proteins (DEPs) in patients with RLS, compared to those in controls, the expression profiles and protein–protein interaction (PPI) network were characterized between dysregulated proteins and extracted proteins involved in iron deficiency, hypoxia, and inflammation responses using the String database (http://string-DB.org). The PPI network was visualized by Cytoscape ver. 3. 7. 1. Statistical analyses of the validation Western blot assays were performed using a Student's t-test.ResultsInteractome network analysis revealed a relationship among the eight proteins, their associated genes, and 150, 47, and 11 proteins related to iron deficiency, inflammation, and hypoxic pathways, respectively. All DEPs were well associated with inflammation, and complement 3, complement C4A, alpha-2 HS glycoprotein, and alpha-2 macroglobulin precursor were found to be in hub positions of networks involved in PPIs including iron deficiency, hypoxia pathway, and inflammation. C3 and C4A were verified using western blotting.ConclusionsWe identified key molecules that represent the selected cellular pathways as protein biomarkers by PPI network analysis. Changes in inflammation can mediate or affect the pathomechanism of RLS and can thus act as systemic biomarkers.     

Response to intravenous iron in patients with iron deficiency anemia (IDA) and restless leg syndrome (Willis–Ekbom disease)

ObjectivesIron 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).MethodsRLS–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.ResultsFollow-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).ConclusionsRLS–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.     

A community-based investigation on restless legs syndrome in a town in China

ObjectiveTo assess the prevalence and severity of restless legs syndrome (RLS) in a town in China and to explore potential factors correlated with the severity of the disease.MethodsFace-to-face home interviews were conducted among a random sample of 2101 residents in one town in China, all aged 16 years and above. An individual questionnaire was administered to all participants to obtain a diagnosis of RLS and other information. An additional questionnaire was then handed out to each patient diagnosed with RLS to collect information on RLS severity and potential factors correlating with RLS severity.ResultsThe prevalence of RLS in the studied population was 7.2%. The prevalence in women was significantly higher than in men and increased with age. Diabetes mellitus, anemia, arthritis, and varicose veins were also associated with RLS. Among the 152 patients, 21.7% were classified as having severe RLS. Multiple correlation analysis reveals that RLS severity was positively correlated with longer disease duration, number of cigarettes smoked per day, and level of work-related physical activity, but negatively correlated with level of leisure time physical activity.ConclusionsRLS is common in the studied population. Lifestyle factors may be associated with RLS severity.