The four diagnostic criteria for Restless Legs Syndrome are unable to exclude confounding conditions ("mimics")

[Practical guidelines for diagnosis and therapy of restless legs syndrome]

Restless legs syndrome (RLS) is the most common neurological sleep disorder affecting 10 % of the Caucasian population. The disorder is characterized by painful sensations in the lower limbs, especially during the evening, at night and during rest, resulting in an urge to move the legs and insomnia. As a result the quality of life is significantly reduced. Dopaminergic agents, opioids and anticonvulsants have proven to be effective for RLS with only the former being currently licensed; however, affected patients have to be identified, which is not always the case, especially in outpatient settings. Possible impediments to the adequate management of patients with RLS may include a lack of awareness, comorbidities and other medical conditions mimicking RLS. To overcome some of these difficulties practical guidelines for the diagnosis and therapy of RLS are provided.

Treatment of restless legs syndrome

Restless legs syndrome (RLS) is a common disorder diagnosed by the clinical characteristics of restlessness in the legs associated often with abnormal sensations that start at rest and are improved by activity, occurring with a diurnal pattern of worsened symptoms at night and improvement in the morning. RLS is the cause of impaired quality of life in those more severely afflicted. Treatment of RLS has undergone considerable change over the last few years. Several classes of medications have demonstrated efficacy, including the dopaminergic agents and the alpha-2-delta ligands. Levodopa was the first dopaminergic agent found to be successful. However, chronic use of levodopa is frequently associated with augmentation that is defined as an earlier occurrence of symptoms frequently associated with worsening severity and sometimes spread to other body areas. The direct dopamine agonists, including ropinirole, pramipexole, and rotigotine patch, are also effective, although side effects, including daytime sleepiness, impulse control disorders, and augmentation, may limit usefulness. The alpha-2-delta ligands, including gabapentin, gabapentin enacarbil, and pregabalin, are effective for RLS without known occurrence of augmentation or impulse control disorders, although sedation and dizziness can occur. Other agents, including the opioids and clonazepam do not have sufficient evidence to recommend them as treatment for RLS, although in an individual patient, they may provide benefit.

Restless legs syndrome associated with exercise intolerance: Data from a retrospective observational clinical neuromuscular center study

INTRODUCTION

Exercise intolerance (EI) is a frequent motive for seeking neuromuscular consultation and may be a sign of metabolic disease or, rarely, muscular dystrophy. The diagnosis is not established in many patients with a typical clinical presentation. Nevertheless, some of them complain of sleep disorders and more especially of restless legs syndrome (RLS).

OBJECTIVE

The objective of our study was to estimate the frequency of RLS in patients presenting with EI.

METHODS

Our retrospective observational study included all patients seen in the center from 2005 to 2011, who were subsequently investigated for EI in the neuromuscular department of the Caen University hospital. Data were collected on clinical RLS and muscular investigations (creatine kinase [CK], EMG, maximal exercise tests magnetic resonance imaging [MRI] and muscle biopsy obtained along with muscle exploration).

RESULTS

Of the 318 patient records analyzed, 84 showed patients accurately complaining of EI. RLS was diagnosed in 25 of these patients (29.7%). This percentage was significantly higher (P<0.001) than found in the general population. Improvement was seen in 91.3% of the patients receiving specific treatment.

CONCLUSION

RLS can sometimes present with pain, potentially worsening with exercise, inappropriately leading to a hypothesis of EI. Clinicians should thus explore the possible diagnosis of RLS when a muscular disease is not found in patients presenting with such symptoms.

Willis-Ekbom Disease Foundation revised consensus statement on the management of restless legs syndrome

Restless legs syndrome (RLS)/Willis-Ekbom disease (WED) is a common disorder, occurring at least twice a week and causing at least moderate distress in 1.5% to 2.7% of the population. It is important for primary care physicians to be familiar with this disorder and its management. Much has changed in its management since our previous algorithm was published in 2004, including the availability of several new drugs. This revised algorithm was written by members of the Medical Advisory Board of the Willis-Ekbom Disease Syndrome Foundation based on scientific evidence and expert opinion. It considers the management of RLS/WED under intermittent RLS/WED, chronic persistent RLS/WED, and refractory RLS/WED. Nonpharmacological approaches, including mental alerting activities, avoiding substances or medications that may exacerbate RLS, and the role of iron supplementation, are outlined. Chronic persistent RLS/WED should be treated with either a nonergot dopamine agonist or a calcium channel α-2-δ ligand. We discuss the available drugs, the factors determining which to use, and their adverse effects. We define refractory RLS/WED and describe management approaches, including combination therapy and the use of high-potency opioids.

A study examining depression in restless legs syndrome

BACKGROUND

Distress is known to occur in RLS subjects consequent to symptoms. However, studies regarding prevalence of depression in RLS are scarce. This study was conducted to find out prevalence of depression in RLS patients and to explore possible underlying factors.

METHOD

112 consecutive RLS subjects presenting to sleep-clinic were included in this study. History regarding RLS, depression and sleep-disturbances was sought. Depression and insomnia were diagnosed using DSM-IV-TR criteria. Subjects were specifically asked whether they had depressive episodes in past one year. Severity of RLS and insomnia was measured using Hindi versions of IRLS and ISI, respectively. Family history of depression and RLS was also asked.

RESULTS

One year prevalence of depression was 41.8%. MDD was reported by 33% and dysthymia by 8.8%. Both the groups were comparable with respects to demographic and clinical features, viz., age, gender, duration, severity and family history of RLS. Duration, number of episodes and severity of insomnia were comparable between groups, so was the family history of depression. In 37.8% of the subjects with MDD, depressive symptoms preceded RLS while in 51.4% of them, they followed onset of RLS. Total duration of RLS symptoms did not correlate with total duration of depression (r(2)=0.07; P=0.64).

CONCLUSION

Clinical depression is seen in more than a third of RLS patients. Depression is not affected by clinical picture of RLS and it is not consequent to sleep disturbance. Perhaps, it is a co-morbid condition.

Restless legs syndrome, pica, and iron status in blood donors

BACKGROUND

The association of blood donation-related iron deficiency with pica or restless legs syndrome (RLS) remains poorly elucidated. This study evaluated the prevalence of RLS and pica in blood donors completing the REDS-II Iron Status Evaluation (RISE) study.

STUDY DESIGN AND METHODS

RISE enrolled 2425 blood donors in a prospective cohort study; 1334 donors provided blood samples to characterize iron status and answered a questionnaire inquiring into symptoms of RLS and pica at a final visit after 15 to 24 months of follow-up. Associations between both conditions and iron status were evaluated.

RESULTS

There were 9 and 20% of donors reporting symptoms of probable or probable/possible RLS, respectively. Iron depletion and donation intensity were not predictive of RLS. Pica was reported by 65 donors (5.5%), half of whom reported daily cravings. Prevalence of pica increased with degree of iron depletion in women (2% in iron-replete females, 13% in those with ferritin < 12 ng/mL), but not in men. Probable RLS and pica coexpressed in eight individuals, but no more frequently than expected by chance.

CONCLUSION

RLS and pica have been associated with iron deficiency in nondonor populations. This study indicates a potentially high prevalence of RLS in frequent blood donors but shows no association with iron status or donation intensity. Low iron stores were associated with higher prevalence of pica, but only in females. Furthermore, the results are incompatible with RLS and pica sharing a common pathophysiology.

Demographic and motor features associated with the occurrence of neuropsychiatric and sleep complications of Parkinson's disease

OBJECTIVE

To determine whether four key neuropsychiatric and sleep related features associated with Parkinson's disease (PD) are associated with the motor handicap and demographic data.

BACKGROUND

The growing number of recognised non-motor features of PD makes routine screening of all these symptoms impractical. Here, we investigated the hypothesis that standard demographic data and the routine assessment of motor signs is associated with the presence of dementia, psychosis, clinically probable rapid eye movement (REM) sleep behavior disorder (cpRBD) and restless legs syndrome (RLS).

METHODS

775 patients with PD underwent standardised assessment of motor features and the presence of dementia, psychosis, cpRBD and RLS. A stepwise feature elimination procedure with fitted logistic regression models was applied to identify which/if any combination of demographic and motor factors is associated with each of the four studied non-motor features. A within-study out-of-sample estimate of the power of the predicted values of the models was calculated using standard evaluation procedures.

RESULTS

Age and Hoehn&Yahr (H&Y) stage were strongly associated with the presence of dementia (p value<0.001 for both factors in the final selected model) while a combination of age, disease duration, H&Y stage, dopamine agonists and catechol-O-methyltransferase (COMT) inhibitors was associated with the presence of psychosis. Disease duration and H&Y stage were the significant indicators of cpRBD, and the lack of significant motor asymmetry was the only significant feature associated with RLS-type symptoms but the evidence of association was weak.

CONCLUSIONS

Demographic and motor features routinely collected in patients with PD can estimate the occurrence of neuropsychiatric and sleep-related features of PD.

Prospective study of restless legs syndrome and mortality among men

OBJECTIVE

To prospectively examine whether men with restless legs syndrome (RLS) had an increased risk of mortality.

METHOD

This was a prospective cohort study of 18,425 US men free of diabetes, arthritis, and renal failure in the Health Professionals Follow-up Study (HPFS). In 2002, RLS was assessed using a set of standardized questions. Deaths were identified from state vital statistics records, the National Death Index, family reports, and the postal system.

RESULTS

During 8 years of follow-up (2002-2010), we documented 2,765 deaths. In an age-adjusted model, RLS was associated with a 39% increased risk of mortality (hazard ratio [HR] = 1.39; 95% confidence interval [CI] 1.19-1.62; p < 0.0001). The association between RLS and mortality was slightly attenuated after further adjustment for body mass index, lifestyle factors, chronic conditions, sleep duration, and other sleep-related disorders (adjusted HR = 1.30; 95% CI 1.11-1.52; p = 0.003). When we further excluded those with major chronic conditions (e.g., cancer, high blood pressure, cardiovascular disease, and other comorbidities), the adjusted HR was 1.92 (95% CI 1.03-3.56; p = 0.04). The interactions between RLS and other risk factors (older age, overweight, short sleep duration, smoking, low physical activity, and unhealthy diet) in relation to total mortality risk were not significant (p for interaction >0.2 for all).

CONCLUSION

We observed that men with RLS had a higher overall mortality and this association was independent of known risk factors. The increased mortality in RLS was more frequently associated with respiratory disease, endocrine disease, nutritional/metabolic disease, and immunologic disorders. Future research exploring the pathophysiologic relationship between these disorders and RLS is warranted.

Restless legs syndrome as a comorbidity in rheumatoid arthritis

Rheumatoid arthritis (RA) is a multisystem disease with a complex immunologic pathophysiology. Likewise, sleep disorders can involve a complicated interplay between the neurologic pathways, immune system, and respiratory system. Recent studies have shown an elevated prevalence of sleep abnormalities in connective tissue disorders compared to the general population. Restless legs syndrome (RLS) may be present in up to 30% of RA patients. These findings may be related to cytokine release and other immunomodulatory responses. TNF- α levels relate to sleep physiology and anti-TNF- α therapy may improve sleep patterns. Most of the patients with this disorder can distinguish their RLS sensations from their arthritic symptoms. RLS is a common comorbidity seen with RA, and prompt recognition and treatment can improve patient quality of life.

Restless legs syndrome and quality of sleep in patients with glomerulopathy

Background

Despite a confirmed association between restless legs syndrome (RLS) and end-stage renal disease (ESRD), there is no study on patients presenting with nephrotic syndrome (NS). To investigate the frequency of RLS and poor quality sleep in NS-patients secondary to primary glomerulopathy with nearly normal glomerular filtration rate (GFR) and its associated factors.

Methods

Patients with NS, defined as 24 h-urine protein greater than 3.5 g/1.73 m² and hypoalbuminemia, (n = 99, 53 women) and a mean age of 36±11 years were studied. Age and sex-matched controls were used to compare RLS and poor sleep quality prevalence. Standardized RLS questionnaire formulated by the International Restless Legs Syndrome and Pittsburgh Sleep Quality Index (PSQI) were used.

Results

RLS was more frequent in NS-patients than in controls (22.8 vs. 4.0%, p = 0.01). Mean time since diagnosis (52.2±34.1 vs. 28.6±22.5 months, p < 0.01) and 24 h-proteinuria (3.7±1.3 vs. 2.6±0.6 g/1.73 m², p = 0.001) were greater in NS-patients with RLS those not presenting RLS. Association between RLS with 24 h-proteinuria [OR = 2.31; p = 0.007; 95% CI 1.87-2.89] and time since diagnosis [OR = 1.10; p = 0.003; CI = 1.02-1.39] were identified even after controlling for age, GFR and diabetes. Sleep quality was poor in NS-patients than in controls (mean PSQI score 7.35±3.7 vs. 5.2±3.0, p = 0.003). In NS-patients, only RLS was associated with poor sleep quality (OR = 1.20; p = 0.004).

Conclusion

Poor quality sleep and RLS are frequent in NS-patients without ESRD. Pathophysiology of this association must be further investigated.

Prospective study of restless legs syndrome and risk of erectile dysfunction

In our previous cross-sectional study, we found that restless legs syndrome (RLS) was associated with erectile dysfunction (ED). Thus, we conducted a prospective study to examine whether RLS was associated with a higher risk of developing ED based on 6 years of follow-up among 10,394 men (mean age = 63.4 years) in the Health Professionals Follow-up Study. RLS was assessed in 2002 using a set of standardized questions recommended by the International RLS Study Group. Erectile function was assessed by means of questionnaires in 2000, 2004, and 2008. We identified 1,633 incident ED cases. Men with RLS were more likely to develop ED (relative risk = 1.38, 95% confidence interval: 1.14, 1.68; P = 0.001) than were those without the syndrome, after adjustment for potential confounders, such as age, body mass index, smoking, physical activity, other sleep disorders, and snoring status. A higher frequency of RLS symptoms was also associated with an increased risk of ED (P(trend) = 0.001). In conclusion, men with RLS had a higher risk of ED, and the magnitude of the risk increased with a higher frequency of RLS symptoms. Combinations of other sleep disorders with RLS further increased the risk of ED.

Validation of the Mayo Sleep Questionnaire to screen for REM sleep behavior disorder in a community-based sample

OBJECTIVE

To validate a questionnaire focused on REM sleep behavior disorder (RBD) in a community-based sample.

BACKGROUND

RBD is a parasomnia manifested by recurrent dream enactment behavior during REM sleep. While confirmation of RBD requires the presence of REM sleep without atonia on polysomnography (PSG), a screening measure for RBD validated in older adults would be desirable for clinical and research purposes.

METHODS

We had previously developed the Mayo Sleep Questionnaire (MSQ) to screen for the presence of RBD and other sleep disorders. We assessed the validity of the MSQ by comparing the responses of subjects' bed partners with the findings on PSG. All subjects recruited from 10/04 to 12/08 in the Mayo Clinic Study of Aging--a population-based study of aging in Olmsted County, Minnesota--who had also undergone a previous PSG were the focus of this analysis.

RESULTS

The study sample included 128 subjects (104 male; median age 77 years [range 67-90]), with the following clinical diagnoses at baseline assessment: normal (n = 95), mild cognitive impairment (n = 30), and mild Alzheimer disease (n = 3). Nine (5%) subjects had RBD based on history and PSG evidence of REM sleep without atonia. The core question on recurrent dream enactment behavior yielded sensitivity (SN) of 100% and specificity (SP) of 95% for the diagnosis of RBD. The profile of responses on four additional subquestions on RBD improved specificity.

CONCLUSIONS

These data suggest that the MSQ has adequate SN and SP for the diagnosis of RBD among elderly subjects in a community-based sample.

Exome sequencing in a family with restless legs syndrome

BACKGROUND

Restless legs syndrome (RLS) has a high familial aggregation. To date, several loci and genetic risk factors have been identified, but no causative gene mutation has been found.

METHODS

We evaluated a German family with autosomal dominantly inherited RLS in 7 definitely and 2 possibly affected members by genome-wide linkage analysis and exome sequencing.

RESULTS

We identified three novel missense and one splice site variant in the PCDHA3, WWC2, ATRN, and FAT2 genes that segregated with RLS in the family. All four exons of the PCDHA3 gene, the most plausible candidate, were sequenced in 64 unrelated RLS cases and 250 controls. This revealed three additional rare missense variants (frequency <1%) of unknown pathogenicity in 2 patients and 1 control.

CONCLUSIONS

We present the first next-generation sequencing study on RLS and suggest PCDHA3 as a candidate gene for RLS.

Restless legs syndrome in children with chronic kidney disease

BACKGROUND

Restless legs syndrome (RLS) is considerably more common among adults with chronic kidney disease (CKD) than in the general population and is associated with increased morbidity and mortality. There is limited information on RLS in children with CKD. Failure to account for conditions that might mimic RLS can lead to overdiagnosis of this syndrome.

METHODS

In a prospective, cross-sectional study, RLS prevalence was compared between pediatric CKD patients and healthy children. RLS was assessed via a questionnaire that included exclusion of mimics. Sleep characteristics and health-related quality of life (HRQoL) were also assessed.

RESULTS

Restless legs syndrome was more prevalent in CKD patients (n = 124) than in 85 normal children (15.3 vs. 5.9 %; p = 0.04). There was no significant association between RLS and CKD stage, CKD etiology, CKD duration, and dialysis or transplant status. Children with RLS were more likely to rate their sleep quality as fairly bad or very bad (41.2 vs. 8.8 %; p = 0.003) and report using sleep medications (42.1 vs. 14.7 %; p = 0.01). RLS was associated with lower HRQoL by parent report (p = 0.03). Only five of the 19 patients (26.3 %) with CKD and RLS had discussed RLS symptoms with a healthcare provider, and only one of these patients had been diagnosed with RLS prior to this study.

CONCLUSIONS

The prevalence of RLS is increased in children with CKD and appears to be underdiagnosed. Systematic screening for RLS and sleep problems would therefore appear to be warranted in children with CKD.

The prevalence and impact of restless legs syndrome on patients with iron deficiency anemia

Restless Legs Syndrome (RLS) a common, under-recognized disorder disrupts sleep and diminishes quality of life. Despite a clear relation between low peripheral iron and increased prevalence and severity of RLS, the prevalence and clinical significance of RLS in iron-deficient anemic (IDA) populations is unknown. In this study all new patients referred for anemia to a community-based hematology practice over a 1-year period (March 2011-2012) were included if they had IDA and no RLS treatment. Patients completed a validated questionnaire identifying RLS, blood tests, and a sleep-vitality questionnaire (SVQ). Patients with RLS were compared to patients with no RLS for differences on SVQ, blood tests, baseline characteristics, and sleep quality. Three hundred forty-three patients were evaluated and 251 (89.2% female, average age of 45.6 years) included in the study. The prevalence of clinically significant RLS (RLS sufferers) was 23.9%, nine times higher than the general population. IDA-RLS sufferers reported poorer quality of sleep, decreased sleep time, increased tiredness, and decreased energy during the day compared to patients with IDA without RLS. Blood tests did not relate to RLS diagnosis but RLS was less likely for African-American than Caucasian patients. Clinically significant RLS occurs commonly with IDA producing much greater disruption of sleep and shorter sleep times than does IDA alone. This indicates the need for identification of RLS with IDA and consideration of appropriate therapeutic interventions for this sizeable subgroup: either aggressive iron treatment to reduce the RLS symptoms or medications for RLS or both.

Ethnic differences in the prevalence and predictors of restless legs syndrome between Hispanics of Mexican descent and non-Hispanic Whites in San Diego county: a population-based study

STUDY OBJECTIVES

To investigate the prevalence and predictors of RLS in Hispanics of Mexican descent (HMD) and non-Hispanic whites (NHW).

DESIGN

A population-based random digit dialing telephone questionnaire.

SETTING

San Diego County California

PARTICIPANTS

1,754 HMD and 1,913 NHW adults ≥ 18 years of age able to participate in a telephone interview in English or Spanish.

INTERVENTIONS

None.

MEASUREMENTS AND RESULTS

RLS was defined by the presence of all 4 criteria of the International Restless Legs Study Group. Sleepiness was measured by the Epworth Sleepiness Scale. Acculturation was evaluated using the Short Acculturation Scale for Hispanics. Risk factors for RLS were by self-report. The survey was conducted in the subject's language of choice. RLS prevalence was significantly lower in HMD than in NHW (14.4% vs.18.3%, p = 0.002). High acculturation HMD had a significantly greater RLS prevalence than the low acculturation group (17.4% vs. 12.8%, p = 0.008). Predictors of RLS varied between HMD and NHW. Female gender (OR 1.40, 95% CI 1.04, 1.90, p = 0.027), smoking (OR 1.82, 95% CI 1.27, 2.61, p = 0.001), and acculturation (OR 1.47, 95% CI 1.10, 1.97, p = 0.009) were independent predictors of RLS in HMD, while only older age (OR 1.01, 95% CI 1.0, 1.02) was an independent predictor of RLS for NHW.

CONCLUSION

The prevalence of RLS was significantly lower in HMD than in NHW, and significantly greater in high acculturation HMD. Our data suggest that risk factors for RLS vary by race/ethnicity and acculturation is an independent risk for RLS in HMD.

Prospective study of restless legs syndrome and coronary heart disease among women

BACKGROUND

Previous cross-sectional studies suggested a positive association between restless legs syndrome (RLS) and coronary heart disease (CHD). This observation was not confirmed by subsequent prospective studies. However, these prospective studies did not take into account the duration of RLS symptoms. Therefore, we prospectively examined whether RLS was associated with an increased risk of CHD in women who participated in the Nurses' Health Study, taking into account the duration of RLS symptoms.

METHODS AND RESULTS

A total of 70 977 women (mean age, 67 years) who were free of CHD and stroke at baseline (2002) were followed up until 2008. Physician-diagnosed RLS was collected via questionnaire. CHD was defined as nonfatal myocardial infarction or fatal CHD. Women with RLS at baseline had a marginally higher risk of developing CHD (multivariable-adjusted hazard ratio, 1.46; 95% confidence interval, 0.97-2.18) compared with women without RLS. The risk was dependent on duration of symptoms: 0.98 (95% confidence interval, 0.44-2.19) for women with RLS for <3 years and 1.72 (95% confidence interval, 1.09-2.73) for women with RLS for ≥3 years (P trend=0.03). The multivariable-adjusted hazard ratios of women with RLS for ≥3 years were 1.80 (95% confidence interval, 1.07-3.01) for nonfatal myocardial infarction and 1.49 (95% confidence interval, 0.55-4.04) for fatal CHD relative to women without RLS.

CONCLUSIONS

We observed that women with RLS for at least 3 years had an elevated risk of CHD. These results suggest that RLS or RLS-associated conditions may contribute to the origin of cardiovascular disease.

Primary headaches in restless legs syndrome patients

Earlier studies conducted among migraineurs have shown an association between migraine and restless legs syndrome (RLS). We chose RLS patients and looked for migraine to exclude sample bias.

Materials and Methods:

99 consecutive subjects of idiopathic RLS were recruited from the sleep clinic during four months period. Physician diagnosis of headache and depressive disorder was made with the help of ICHD-2 and DSM-IV-TR criteria, respectively. Sleep history was gathered. Severity of RLS and insomnia was measured using IRLS (Hindi version) and insomnia severity index Hindi version, respectively. Chi-square test, one way ANOVA and t-test were applied to find out the significance.

Results:

Primary headache was seen in 51.5% cases of RLS. Migraine was reported by 44.4% subjects and other types of ‘primary headaches’ were reported by 7.1% subjects. Subjects were divided into- RLS; RLS with migraine and RLS with other headache. Females outnumbered in migraine subgroup (χ²=16.46, P<0.001). Prevalence of depression (χ²=3.12, P=0.21) and family history of RLS (χ²=2.65, P=0.26) were not different among groups. Severity of RLS (P=0.22) or insomnia (P=0.43) were also similar.

Conclusion:

Migraine is frequently found in RLS patients in clinic based samples. Females with RLS are prone to develop migraine. Depression and severity of RLS or insomnia do not affect development of headache.

Translation and validation of International Restless Leg Syndrome Study Group rating scale in Hindi language

OBJECTIVES

The objective of this study is to translate and validate the International Restless Leg Syndrome Study Group rating scale (IRLS) in Hindi language.

MATERIALS AND METHODS

Thirty one consecutive patients diagnosed of Restless Leg Syndrome (RLS) were included in the study. Control group comprised of 31 subjects not having any symptom of RLS. The scale was procured from MAPI research trust; and, permission for the translation was sought. The translation was done according to the guidelines provided by the publisher. After translation, final version of the scale was applied in both the groups to find out the reliability and clinical validity.

RESULTS

RLS group had a predominance of females, and they were younger than the male counterparts (Age=36.80 ± 10.46 years vs 45.18 ± 8.34 years; t=2.28; P=0.03). There was no difference in the mean age between groups (RLS=39.77 ± 10.44 years vs Non RLS=38.29 ± 11.29 years; t=-0.53; P=0.59). IRLS scores were significantly different between both groups on all items (P<0.001). Translated version showed high reliability (Cronbach's alpha=0.86). IRLS scores were significantly different between both groups on all items (P<0.001).

CONCLUSION

Hindi version of IRLS is reliable and a clinically valid tool that can be applied in Hindi speaking population.

Sleep–wake problems in patients with amyotrophic lateral sclerosis: implications for patient management

SUMMARY Sleep–wake problems are frequent, although unrecognized, complications of amyotrophic lateral sclerosis (ALS). Sleep disorders such as insomnia, sleep-disordered breathing and restless legs syndrome have all been reported in patients with ALS, despite the limited number of studies and the small populations investigated so far. Sleep disturbances gradually worsen with disease progression, suggesting a relationship between the severity of disease and the neurodegenerative process. However, poor sleep can also be a consequence of several disturbances such as anxiety, depression, pain, choking, sialorrhea, fasciculations, cramps, nocturia and the inability to get comfortable and move freely in bed. Sleep disorders may have many reflections on patients with ALS, including excessive daytime somnolence, fatigue, impaired cognition, reduced quality of life and survival. This article reviews the recent literature on sleep–wake problems in patients with ALS, focusing on the implications for patient management.

Association of multiple sclerosis with restless legs syndrome and other sleep disorders in women

OBJECTIVE

To assess the association of multiple sclerosis (MS) with concurrent restless legs syndrome (RLS) and daytime sleepiness. We also prospectively examined whether women with MS had an increased risk of developing RLS during 4 years of follow-up.

METHODS

The main analysis was based on a cross-sectional study of 65,544 women (aged 41-58 years) free of diabetes, arthritis, and pregnancy, who were participating in the Nurses' Health Study II cohort. Participants were considered to have RLS if they met 4 RLS diagnostic criteria recommended by the International Restless Leg Syndrome Study Group and had restless legs ≥ 5 times/month. MS was self-reported and confirmed by medical record review.

RESULTS

Among women with MS, the prevalence of RLS and severe RLS (15+ times/month) were 15.5% and 9.9% in 2005, respectively, relative to 6.4% and 2.6% among women without MS. After adjustment for potential confounders and the presence of other sleep disorders, women with MS had a higher likelihood of having RLS (odds ratio [OR] = 2.72, 95% confidence interval [CI] 1.89-3.93), severe RLS (OR = 4.12, 95% CI 2.65-6.42), and daily daytime sleepiness (OR = 2.11, 95% CI 1.31-3.42) compared with women without MS. Among the 172 women who had MS and were free of RLS in 2005, 9 developed RLS (5.2%) during a 4-year period and all had severe RLS. The adjusted relative risk of severe RLS was 3.58 (95% CI 1.53-8.35), comparing women with MS at baseline with those without MS.

CONCLUSION

Women with MS had a significantly higher prevalence of RLS and daytime sleepiness and an increased risk of developing RLS in the future.

Are we aware of restless legs syndrome in COPD patients who are in an exacerbation period? Frequency and probable factors related to underlying mechanism

A few previous studies have reported that the patients with chronic obstructive pulmonary disease (COPD) have a 29.1% to 36.8% frequency of restless legs syndrome (RLS). In this study, we observed RLS symptoms in patients experiencing COPD exacerbation to better understand the relationship between the many clinical parameters of COPD and the presence of RLS and to attract the attention of specialists on the association between the two conditions. Twenty-two male patients in COPD exacerbation; 17 healthy individuals were evaluated in this study. The patients were evaluated using the 2003 RLS symptom criteria outlined by the International Restless Legs Syndrome Study Groups (IRLSSG). The Pittsburgh Sleep Quality Index and Epworth daytime sleepiness scale were used to assess the sleep quality of patients. The RLS symptoms were correlated with blood levels of laboratory and clinical parameters. Statistical analyses were performed using SPSS 17.0 statistical software packet. The Pittsburgh Sleep Quality Index and Epworth daytime sleepiness scale scores were increased in COPD patients and correlated significantly with RLS symptoms. It was found that 54.5% of COPD patients with acute exacerbations were observed to have RLS symptoms. The Pittsburgh Sleep Quality Index was significantly higher in COPD patients with RLS symptoms compared to COPD patients without RLS symptoms (p < 0.05). We did not observe any significant difference in the previously reported metabolic and clinical parameters associated with RLS in COPD patients with and without RLS. RLS symptoms increase during COPD exacerbation and lead to decreased sleep quality.

Suggested immobilization test for diagnosis of restless legs syndrome in Parkinson's disease

Diagnosis of restless leg syndrome (RLS) in Parkinson's disease (PD) is difficult because of clinical confounds. The suggested immobilization test (SIT) is validated for diagnosis of primary RLS. This study evaluated the usefulness of the SIT for diagnosis of RLS in PD. We compared SIT scores, as well as polysomnography measures in 50 patients with PD (25 with RLS, 25 without), 25 patients with primary RLS, and 25 age/sex matched controls. Mean leg discomfort score was increased in patients with PD and RLS compared to PD without RLS, and also in patients with primary RLS compared to controls. Leg discomfort was significantly higher at the end of the test in patients with RLS compared to patients without RLS. Intensity of leg discomfort was similar between patients with RLS, with or without PD. Using a mean leg discomfort cutoff of 11, we showed sensitivity of 91% and specificity of 72% for RLS diagnosis in PD during symptomatic time intervals. Periodic leg movements index during the SIT did not differ between groups. Periodic leg movements index during sleep and wakefulness was increased in patients with primary RLS compared to controls, but did not differ between patients with PD, with and without RLS. The sensory SIT is a simple test that may help diagnose RLS in patients with PD.

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

OBJECTIVE

To 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.

METHODS

Face-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.

RESULTS

The 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.

CONCLUSIONS

RLS is common in the studied population. Lifestyle factors may be associated with RLS severity.

Restless legs syndrome and hypertension in middle-aged women

Limited research suggests a relationship between restless legs syndrome and hypertension. We, therefore, assessed the relationship between restless legs syndrome and hypertension among middle-aged women. This is a cross-sectional study including 65 544 women (aged 41-58 years) participating in Nurses' Health Study II. The participants with diabetes mellitus and arthritis were excluded, because these conditions can mimic restless legs syndrome. Restless legs syndrome was assessed by a self-administered questionnaire based on the International Restless Legs Study Group criteria. Information on diagnosis of hypertension and blood pressure values were collected via questionnaires. Multivariable logistic regression models were used to analyze the relation between restless legs syndrome and hypertension, with adjustment for age, race, body mass index, physical activity, menopausal status, smoking, use of analgesics, and intake of alcohol, caffeine, folate, and iron. Compared with women with no restless legs symptoms, the multiple adjusted odds of having hypertension were 1.20 times (95% CI: 1.10-1.30; P<0.0001) higher among women with restless legs symptoms. The adjusted odds ratios for women who reported restless legs symptoms 5 to 14 times per month and ≥15 times per month were 1.06 (95% CI: 0.94-1.18) and 1.41 (95% CI: 1.24-1.61) respectively, compared with those without the symptoms (P trend: <0.0001). Greater frequency of restless legs symptoms was associated with higher concurrent systolic and diastolic blood pressures (P trend: <0.0001 for both). Women with restless legs syndrome have a higher prevalence of hypertension, and this prevalence increases with more frequent restless legs symptoms.

Development of a next day functioning measure to assess the impact of sleep disturbance due to restless legs syndrome: the restless legs syndrome-next day impact questionnaire

OBJECTIVES

Symptoms of Restless Legs Syndrome (RLS) affect patients' quality and duration of sleep, which can have next day sequelae detrimental to daytime performance. To date, no measure sufficiently assesses such sequelae. This study aimed to develop a new self-reported outcome measure to assess the impact of disturbed sleep due to RLS on next day functioning and to support its content validity.

METHODS

The development of the Restless Legs Syndrome-Next Day Impact (RLS-NDI) questionnaire included concept elicitation interviews with RLS patients in the United States (n=20); grounded theory data collection and analysis methods; and review by clinical and measurement experts to generate items, responses, and instructions. Cognitive interviews (n=15) were conducted to ensure understanding of the RLS-NDI, concept comprehensiveness, and identification of any necessary item revisions.

RESULTS

Impacts on next day functioning attributed to disturbed sleep due to RLS symptoms included activities of daily living (i.e., work, household chores), cognitive functioning (i.e., concentration, forgetfulness, mental tiredness, alertness), emotional functioning (i.e., irritability, depressed mood), physical functioning (i.e., physical tiredness, active leisure activities), energy, daytime sleepiness, and social functioning (i.e., relationships, social activities/situations). The final measure consists of 14 items assessed "today" and rated on a numeric rating scale.

CONCLUSIONS

The RLS-NDI is an evaluative tool with demonstrated content validity.

Epidemiology of restless legs syndrome: a synthesis of the literature

Restless legs syndrome (RLS) has gained considerable attention in the recent years: nearly 50 community-based studies have been published in the last decade around the world. The development of strict diagnostic criteria in 1995 and their revision in 2003 helped to stimulate research interest on this syndrome. In community-based surveys, RLS has been studied as: 1) a symptom only, 2) a set of symptoms meeting minimal diagnostic criteria of the international restless legs syndrome study group (IRLSSG), 3) meeting minimal criteria accompanied with a specific frequency and/or severity, and 4) a differential diagnosis. In the first case, prevalence estimates in the general adult population ranged from 9.4% to 15%. In the second case, prevalence ranged from 3.9% to 14.3%. When frequency/severity is added, prevalence ranged from 2.2% to 7.9% and when differential diagnosis is applied prevalence estimates are between 1.9% and 4.6%. In all instances, RLS prevalence is higher in women than in men. It also increases with age in European and North American countries but not in Asian countries. Symptoms of anxiety and depression have been consistently associated with RLS. Overall, individuals with RLS have a poorer health than non-RLS but evidence for specific disease associations is mixed. Future epidemiological studies should focus on systematically adding frequency and severity in the definition of the syndrome in order to minimize the inclusion of cases mimicking RLS.

Prevalence of restless legs syndrome in North American and Western European populations: a systematic review

BACKGROUND

Restless legs syndrome (RLS) is a potentially debilitating sleep disorder that affects a significant percentage of North American and European adults. Although standardized RLS diagnostic criteria are now established and widely accepted, reported prevalence estimates have varied widely. In this paper, we review the literature regarding RLS prevalence in North American and Western European adult populations, examine potential sources of variation, briefly discuss the impact of RLS, and offer recommendations for future research.

METHODS

To identify qualifying studies, we searched 6 scientific databases and scanned bibliographies of relevant review papers and all identified articles. Studies including fewer than 300 participants, that did not use any of the 4 standard diagnostic criteria, were published prior to 1995 or targeted clinical populations were excluded.

RESULTS

Thirty-four papers detailing results of large, population-based studies in 16 North American and Western European countries met our inclusion criteria, including 5 multi-country studies (N=69,992 participants) and 29 single country studies (N=163,188 participants); all but one were cross-sectional. Reported general prevalence rates ranged from 4% to 29% of adults, averaging 14.5±8.0% across studies. Reported prevalence averaged higher in primary care populations than in populations derived from random sampling or geographically defined cohorts (19.5±7.9% vs. 12.3±7.2%). Diagnostic and severity criteria differed considerably among studies, as did inclusion criteria, with corresponding variation in prevalence estimates. Prevalence averaged higher in women and older adults; more limited data suggest race/ethnicity, parity, health status, and other factors may also contribute to the observed variation in prevalence. RLS has profound, negative effects on health, well-being, and quality of life, yet detection rates remain low.

CONCLUSIONS

Collectively, these studies indicate that RLS is a common disorder of major clinical and public health significance in the Western industrialized world, affecting between 4% and 29% of adults. The wide variation in reported prevalence likely reflects differences in demographic factors, health status, and other population characteristics; study population source and sampling frame; and inconsistencies in RLS diagnostic criteria and procedures. Prospective studies and corresponding incidence data on RLS are lacking, hindering the evaluation of both causal factors and sequelae.

[Restless legs syndrome and nocturnal leg pain : Differential diagnosis and treatment]

Pain in the legs belongs to the five most frequent regional pain symptoms. Restless legs syndrome (RLS) presents a particular differential diagnosis for pain in the legs, which is characterized by a nocturnal urge to move the legs often associated with painful sensations in the legs. It is one of the most common neurological disorders and probably the leading cause of nocturnal pain in the legs. In this overview, the diagnosis and therapy of RLS as well as aspects of pain therapy of the disorder are presented. In addition, the differential diagnoses for exclusion of other specific causes of nocturnal pain in the legs are discussed.

Evaluation of contributing factors to restless legs syndrome in migraine patients

Recent studies have provided evidence for a positive association between migraine and restless legs syndrome (RLS), although the exact mechanisms and contributing factors remain unclear. A cross-sectional, case-control study was conducted, including patients with migraine (n = 262) and headache-free control subjects (n = 163). Migraine was diagnosed according to International Classification of Headache Disorders II criteria. RLS diagnosis was made based on four essential criteria as described by the International Restless Legs Syndrome Study Group. All patients completed the Migraine Disability Assessment (MIDAS) questionnaire, Beck Depression Inventory (BDI)-II scores, Pittsburgh Sleep Quality Index (PSQI), and Epworth Sleepiness Scale (ESS). A total of 210 blood samples were collected to correlate various parameters with RLS. RLS frequency was significantly greater in patients with migraine than in controls (13.7 vs. 1.8%). Migraine patients with RLS had high scores for MIDAS, BDI-II, PSQI, and ESS compared with those without RLS. In addition, migraine patients with RLS had a high rate of smoking and RLS family history, as well as increased levels of serum phosphorus and urea nitrogen compared with those without RLS. However, there was no difference in serum iron and ferritin levels between the groups. In migraine patients, logistic regression analysis revealed that positive RLS family history, BDI-II, ESS, and serum phosphorus levels were significant RLS predictors. Our study confirmed a positive association between RLS and migraine. RLS comorbidity in migraine patients was associated with insomnia, daytime sleepiness, depressive symptoms, headache-related disability, and increased serum phosphorus levels. These findings may provide a better understanding of RLS pathogenesis in migraine.

Validation of the post sleep questionnaire for assessing subjects with restless legs syndrome: results from two double-blind, multicenter, placebo-controlled clinical trials

BACKGROUND

Because of the subjective nature of Restless Legs Syndrome (RLS) symptoms and the impact of these symptoms on sleep, patient-reported outcomes (PROs) play a prominent role as study endpoints in clinical trials investigating RLS treatments. The objective of this study was to validate a new measure, the Post Sleep Questionnaire (PSQ), to assess sleep dysfunction in subjects with moderate-to-severe RLS symptoms.

METHODS

Pooled data were analyzed from two 12-week, randomized, placebo-controlled trials of gabapentin enacarbil (N = 540). At baseline and Week 12, subjects completed the PSQ and other validated health surveys: IRLS Rating Scale, Clinical Global Impression of Improvement (CGI-I), Profile of Mood States (POMS), Medical Outcomes Study Scale-Sleep (MOS-Sleep), and RLS-Quality of Life (RLSQoL). Pooled data were used post hoc to examine the convergent, divergent, known-group validity and the responsiveness of the PSQ.

RESULTS

Convergent validity was demonstrated by significant correlations between baseline PSQ items and total scores of IRLS, POMS, RLSQoL, and the MOS-Sleep Scale (p ≤ 0.007 each). Divergent validity was demonstrated through the lack of significant correlations between PSQ items and demographic characteristics. Correlations (p < 0.0001) between RLS severity groups and PSQ items demonstrated known-group validity. Mean changes in investigator- and subject-rated CGI-I scores for each PSQ item (p < 0.0001) demonstrated the PSQ's responsiveness to patient change as reported by their care provider.

CONCLUSIONS

Although these analyses were potentially limited by the use of clinical trial data and not prospective data from a study conducted solely for validation purposes, the PSQ demonstrated robust psychometric properties and is a valid instrument for assessing sleep and sleep improvements in subjects with moderate-to-severe RLS symptoms.

TRIAL REGISTRATION

This study analyzed data from two registered trials, NCT00298623 and NCT00365352.

Update in restless legs syndrome

PURPOSE OF REVIEW

Although restless legs syndrome (RLS) is a disorder recognized in the medical literature since the 17th century, there have only recently been significant clinical and scientific advances in diagnosis, epidemiology and understanding the disorder, mainly due to the advent of dopaminergic treatment.

RECENT FINDINGS

Recent discoveries have uncovered the iron-dopamine connection in RLS and the basic dopaminergic pathology related to the RLS symptoms. These have led to new understanding of the morbidity of RLS and the many conditions associated with RLS, which have also supported new approaches to treatment. These developments are each briefly described here.

SUMMARY

Although there has been progress in understanding, diagnosing and treating RLS, it remains an underdiagnosed and undertreated condition severely impairing functioning of patients with moderate-to-severe disease. Much work is needed to improve on current, as well as other novel therapies.