Restless legs syndrome in hemodialysis patients: health-related quality of life and laboratory data analysis

Restless Leg Syndrome in Hemodialysis Patients: A Narrative Review

BACKGROUND

Restless legs syndrome (RLS) is a clinical entity characterized by sensory-motor manifestations commonly observed in end-stage renal illness. Evidence suggests that RLS is a multifactorial phenomenon that can be influenced by many critical factors, including genetic predisposition, dietary patterns, and deficiency in some vitamins. Iron metabolism disorders and metabolic derangements have been generally accepted as predisposing elements in RLS. Furthermore, both pharmacological and neuroimaging studies demonstrated dopamine deficiency and dopamine receptors decrease in basal ganglia during RLS.

REVIEW SUMMARY

A literature search was done in three databases (PubMed, Google Scholar, and Cochrane) to identify the pertinent articles discussing the epidemiology, pathogenesis, and management of RLS in hemodialysis patients. RLS can affect the morbidity and mortality of patients treated with dialysis. It also has significant impacts on the quality of life since it can lead to insomnia, increased fatigue, mental health troubles, and other movement problems. Appropriate measures should be considered in this particular population so to prevent and treat RLS. Many drugs and other nonpharmacological methods have been investigated to attenuate the disease's severity. No treatment, however, could offer long-term effects.

CONCLUSION

Further efforts are still required to improve the understanding of RLS pathogenic trends to find more specific and efficient therapies. A wide range of treatment options is available. However, it can be individualized according to the patients' several factors.

Sleep disorders in children and adolescents on regular hemodialysis

Sleep disorders in children with chronic kidney disease have been assessed in a limited number of studies. Our aim was to characterize the types of sleep disorders in children on regular hemodialysis and to detect the predictors of sleep efficiency in those children. Forty children and adolescents on regular hemodialysis and another 40 age- and gender-matched control groups were interviewed to answer a questionnaire-based survey, a modified Epworth Sleepiness Scale, to assess excess daytime sleepiness. Also, they underwent an overnight in-laboratory polysomnography to assess total sleep time, sleep efficiency, sleep staging, apnea/hypopnea index, and periodic limb movement index. We found poor sleep efficiency in 20% of cases, and periodic limb movement index higher than 5 in 45%, and apnea/hypopnea index higher than 5 in 40%. There was significant negative correlation between sleep efficiency on one hand, and serum potassium, serum creatinine, and sleep onset on other hand (p < 0.001, p < 0.001, and p < 0.001, respectively). There was significant decrease in hemoglobin, serum iron, and transferrin saturation in patients with excess daytime sleepiness (p < 0.001, p = 0.003, and p = 0.010, respectively). By using multivariate linear regression analysis, we found that serum creatinine was the single independent predictor of sleep efficiency.Conclusion: Poor sleep quality is not uncommon in hemodialysis children. Our results show a lower frequency of sleep disorders in comparison with previous studies. There is a strong association between kidney dysfunction and poor sleep quality in HD children.What is known:• Sleep disturbances can adversely affect a child's daytime performance.• Sleep disorders in children with chronic kidney disease have been assessed in only a limited number of studies.What is new:• Poor sleep quality is not uncommon in hemodialysis children.• There is a strong association between kidney dysfunction and poor sleep quality in hemodialysis children.

Restless legs syndrome effectively treated with constant-pressure predilution online hemodiafiltration

BACKGROUND

We encountered a case of unstable predilution online HDF due to elevated transmembrane pressure (TMP) when performing constant-speed predilution online hemodiafiltration (HDF) as treatment for restless legs syndrome (RLS) in a dialysis patient. We report the effectiveness of incorporating a newly developed constant-pressure predilution online HDF system as a preventive measure against unstable online HDF and frequent adjustment of settings when treating dialysis patients with RLS.

CASE PRESENTATION

A 55-year-old man had suffered from RLS and been undergoing constant-speed online HDF with 45 L target predilution and an ABH-21P hemodiafilter. The symptoms of RLS rated 10 on the International Restless Legs Syndrome Rating Scale (IRLS). The α1-microglobulin (α₁-MG) removal rate was only 27.8%, so the hemodiafilter was subsequently replaced with a PEPA hemodiafilter. However, episodes of elevated TMP exceeding 250 mmHg occurred frequently after the replacement and were managed by reducing dialysate flow rate. Therefore, we incorporated a constant-pressure predilution online HDF that maintains TMP below 200 mmHg. The amount of replacement was maintained at approximately 43.5 ± 6.98 L and the α₁-MG removal rate was 39.5%, with no need to manually reduce the flow rate. The Alb leakage in dialysate waste was 7.9 g. The patient has maintained an IRLS rating of 0 with no RLS symptoms for the past 4 years.

CONCLUSIONS

Using the constant-pressure mode enabled achieved the clinical endpoint, namely, resolution of RLS with no need to manually reduce the flow rate.

Restless Legs Syndrome in Dialysis Patients: Does the Dialysis Modality Influence Its Occurrence and Severity?

Background

Restless legs syndrome (RLS) is more prevalent in chronic kidney patients than in the general population, but it is often diagnosed late and its predictors are unknown.

Purpose

To diagnose RLS in a group of chronic kidney patients on dialysis, determine its frequency and severity, compare the prevalence and severity of the condition among dialytic modalities, and identify possible predictive factors in this population.

Methods

An observational and cross-sectional study with 326 patients who had been on dialysis for more than 3 months, 241 on hemodialysis (HD) and 85 on automatic peritoneal dialysis (APD), using the criteria established by the International Study Group on RLS for the diagnosis and the RLS Rating Scale to determine its severity.

Results

RLS was diagnosed in 19.3% of the patients, 52.4% with severe or very severe forms. Patients with and without RLS did not differ in clinical and demographic characteristics and dialytic modality; however, patients on APD presented higher RLS severity compared to the HD group.

Conclusions

RLS is frequent in dialysis patients and occurs predominantly in its most severe forms; the dialytic modality seems to have no influence on its occurrence; however, it is more severe in patients on APD.

Sleep disorders in dialysis patients

Poor sleep and sleep-related breathing disorders are common in patients with end-stage renal disease (ESRD) but are often unrecognized and undertreated. Sleep disorders are known negative prognostic factors for morbidity and mortality. The most frequent sleep disorders seen in patients with ESRD are conditioned insomnia, excessive daytime sleepiness, obstructive or central sleep apnea (SA), as well as restless legs syndrome (RLS) and periodic limb movement disorder (PLMD). Several uremic and nonuremic factors are thought to participate in the pathogenesis of sleep disorders in patients with ESRD. The therapy of sleeping disorders includes nonpharmacological and pharmacological measures that can improve the functionality and quality of life in patients with ESRD.

Association of restless legs syndrome and mortality in end-stage renal disease: an analysis of the United States Renal Data System (USRDS)

Background

Objective of the study is to assess prevalence and survival among end stage renal disease patients with restless legs syndrome (RLS) within a national database (USRDS).

Methods

A case-control, retrospective analysis was performed. Differences in characteristics between the groups, RLS and those with no sleep disorder (NSD), were determined using χ2 tests. Cox proportional hazard regression was used to assess survival between those with RLS and propensity score matched controls.

Results

Cases of restless legs syndrome were defined as patients that had received an ICD-9 code of 333.94 at any point during their treatment (n = 372). RLS group demonstrated a significantly higher proportion of patients with major depressive disorder, dysthymic disorder, anxiety, depression, minor depressive disorder, and psychological disorder. The difference between the survival was not statistically significant in those without sleep disorder as compared to those with RLS (HR =1.16±0.14, p = 0.3).

Conclusions

True prevalence of RLS in dialysis patients can only be estimated if knowledge gap for care providers in diagnosis of RLS is addressed. RLS patients also have increased incidence of certain psychological disorders which needs to be addressed.

Electronic supplementary material

The online version of this article (doi:10.1186/s12882-017-0660-0) contains supplementary material, which is available to authorized users.

Restless leg syndrome in chronic hemodialysis patients in Mashhad hemodialysis centers

Introduction: Restless leg syndrome (RLS) is a sensory motor disorder. Patients with this syndrome have serious and uncontrollable desire to move their legs, which is mostly due to an uncomfortable feeling intensified when they are motionless. It may be a genetic disorder or secondary to iron deficiency, neurodegenerations, pregnancy, some drugs and severe kidney diseases.

Objectives: This study was designed to find out the prevalence and its risk factors of RLS in hemodialysis patients.

Patients and Methods: This multicenter cross-sectional study was done on 260 hemodialysis patients. The prevalence of RLS was measured using International Restless Legs Syndrome Study Group (IRLSSG)’s RLS Questionnaire (RLSQ). Potential risk factors for RLS including underlying cause of chronic renal failure, duration on dialysis, biochemical tests, dialysis adequacy, and erythropoietin and also venofer dosage in recent month and demographic data were also evaluated.

Results: The prevalence of RLS was 55% including 59.4% males and 40.6% females. Their mean age of RLS patients and their dialysis duration were significantly higher than other group (P<0.05). Their body mass index (BMI) and serum calcium were significantly higher (P<0.05). However erythropoietin dosage and serum hemoglobin level were lower in RLS patients (P<0.05). Significant predictors of RLS were history of diabetes mellitus (DM), hypertension (HTN), smoking (P<0.05). There was not significant relation between RLS and dialysis adequacy, serum intact parathyroid hormone (iPTH), urea, ferritin and venofer dosage (P>0.05).

Conclusion: According to the results, RLS is a common disorder in hemodialysis patients which can affect strongly on their life. So particular attention and sooner diagnosis of RLS in high risk patients for better management is necessary.

Prevalence of Restless Legs Syndrome in Patients with Inflammatory Bowel Disease

BACKGROUND AND AIM

There has been increased interest in sleep disorders in patients with inflammatory bowel disease (IBD). Studies in North America and Europe reported that the prevalence of restless legs syndrome (RLS) is much higher in patients with Crohn's disease (CD) than in the general population. The aim of this study was to reveal the prevalence and clinical features of RLS in Japanese patients with IBD and investigate the influence of RLS on sleep quality and quality of life (QOL).

METHODS

The study included 80 outpatients with IBD who visited Nagasaki University Hospital between December 2012 and July 2014. All patients completed the international RLS study group rating scale, a validated measure of the presence of RLS. Sleep quality was assessed using the Japanese version of the Pittsburgh Sleep Quality Index (PSQI), and health-related QOL was assessed using the Japanese version of the 36-item short form healthy profile (SF-36) version 2.

RESULTS

The prevalence of RLS in patients with IBD was 20%, including rates of 21.7% in patients with ulcerative colitis (UC) and 17.6% in patients with CD. Among patients with CD, the proportion of women and serum level of CRP were higher in the RLS group than in the non-RLS group. Among those with UC, there were no differences in clinical characteristics between the RLS and non-RLS groups. Patients in the RLS group slept significantly less well than those in the non-RLS group (PSQI > 5; 62.5 vs. 34.4%, P < 0.05). No significant relationships were observed between QOL indices and the presence of RLS (SF-36 physical score, 46.8 vs. 50.1; mental score, 43.8 vs. 45.7; role/social score, 48.1 vs. 49.2).

CONCLUSIONS

RLS occurs frequently in Japanese patients with UC as well as CD. RLS affects sleep quality but not QOL, and it should be considered one of the causes of sleep disturbance in patients with IBD.

Clinical management of restless legs syndrome in end-stage renal disease patients

Restless legs syndrome (RLS) is a common neurological movement disorder, characterized by restless and unpleasant sensations in the deep inside of legs. The symptoms of RLS are less noticeable during daytime, but more prevalent at night. Therefore, the disorder can induce low quality of life, insomnia, and impairment of daytime activity. RLS in end-stage renal disease (ESRD) patients is especially problematic due to premature discontinuation of dialysis and increased mortality. The prevalence of RLS among dialysis patients is much higher compared to the prevalence of the same disorder in patients with normal renal functions. Even though there are recommended treatment guidelines for the general population established by Medical Advisory Board of the RLS foundation, which include the use of dopamine agonists, levodopa, gabapentin, benzodiazepines, and opioids, limited information is available on the effects of these therapies in ESRD patients. Since the existing clinical data were extrapolated from small sample sizes in short-term clinical trials, further clinical studies are still needed to better assess the efficacy, safety, and tolerability of these medications in patients with ESRD.

Sleep disturbance and depressive affect in patients treated with haemodialysis

BACKGROUND

Sleep disorders and depression are prevalent conditions in patients with end-stage kidney disease. These co-morbidities have significant overlap and compounded morbidity and mortality burden. This overlap presents challenges to optimal clinical assessment and treatment. The goal of this study was to assess the prevalence of sleep disturbance in patients on maintenance haemodialysis, and to assess the impact of depressive affect.

OBJECTIVES

This was a single-site, single group, cross-sectional study of 69 English-speaking patients undergoing maintenance haemodialysis. Self-reported assessments included those of sleep quality (Pittsburgh Sleep Quality Index), depression (Beck Depression Inventory), daytime sleepiness (Epworth's Sleepiness Scale), a dialysis-specific sleep questionnaire, and standard laboratory values. No objective sleep information was collected.

METHOD

All participants were well dialysed, and represented all four daily shifts. Fifty-eight per cent reported clinically significant sleep difficulty, with elevated yet sub-threshold daytime sleepiness. Mean depressive affect was also elevated, yet sub-diagnostic and was positively correlated with increased age.

RESULTS

Participants scoring above the diagnostic threshold for depression had significantly more disturbed sleep quality, more daytime sleepiness and had more problems sleeping due to restless leg syndrome than people with minimal depressive affect.

CONCLUSION

Poor sleep quality is prevalent in patients on maintenance haemodialysis, and is associated with increased daytime sleepiness. Depression further compounds this relationship, and is significantly associated with increased daytime sleepiness and restless leg syndrome.

Prevalence of restless legs syndrome in chronic kidney disease: a systematic review and meta-analysis of observational studies

INTRODUCTION

Nowadays prevalence of restless legs syndrome (RLS) in chronic kidney disease (CKD) patients was reported in many studies, while the results varied. The aim of our study was to investigate the prevalence of RLS in this population, considering different data collecting measures and diagnostic criteria.

METHODS

MEDLINE, Embase, PsycINFO, and Scopus databases were searched for relevant studies. We limited the analyses to studies using clinical interview or questionnaire for diagnosis. Univariate meta-regression analysis was preformed to assess the effects of the disease-related covariates on prevalence estimates. Comprehensive Meta-Analysis 2.0 was used to perform the meta-analysis.

RESULTS

Fifty-one studies were included in the analysis. Prevalence of RLS was varied by renal function and diagnostic methods. Overall prevalence in CKD populations was 24.2% (95%CI, 20.1-28.7). Pooled prevalence of RLS was higher in patients diagnosed by questionnaire than by clinical interview [26.2% (95%CI, 17.9-36.5) vs. 23.6% (95%CI, 19.6-28.1)]. When grouped by CKD setting, the prevalence was 28.4% (95%CI, 24.6-32.6) in dialysis patients, followed by early stages patients [9.9% (95%CI, 5.4-17.5)], and kidney transplant recipients [6.7% (95%CI, 5.6-7.8)].

CONCLUSIONS

Our meta-analysis suggested that more than one-quarter of CKD sufferers, especially those who were on dialysis, were plagued by RLS. Higher sensitivity of diagnostic criteria in interview may be valuable for timely treatment.

Sleep disorders and chronic kidney disease

Sleep disorders have a profound and well-documented impact on overall health and quality of life in the general population. In patients with chronic disease, sleep disorders are more prevalent, with an additional morbidity and mortality burden. The complex and dynamic relationship between sleep disorders and chronic kidney disease (CKD) remain relatively little investigated. This article presents an overview of sleep disorders in patients with CKD, with emphasis on relevant pathophysiologic underpinnings and clinical presentations. Evidence-based interventions will be discussed, in the context of individual sleep disorders, namely sleep apnea, insomnia, restless leg syndrome and excessive daytime sleepiness. Limitations of the current knowledge as well as future research directions will be highlighted, with a final discussion of different conceptual frameworks of the relationship between sleep disorders and CKD.

Restless Legs Syndrome: Associated Risk Factors in Hemodialysis Patients

Background:

Restless legs syndrome (RLS) may be associated with increased morbidity and mortality among end-stage renal disease (ESRD) patients; however, it is a disorder that is neglected in dialysis centers.

Objectives:

The goal of this study was to investigate the clinical factors associated with RLS among ESRD patients.

Patients and Methods:

This cross-sectional study was conducted on ESRD patients undergoing maintenance hemodialysis (HD) in three HD centers in Ahvaz city in Southwest Iran. Blood samples were obtained prior to a dialysis session to check the routine laboratory test results and assess the adequacy of dialysis. The presence of RLS was assessed by using the international RLS study group (IRLSSG) diagnostic criteria. The IRLSSG rating scale was also used to evaluate the severity of the RLS symptoms.

Results:

Of the 139 HD patients enrolled in this study, 60 were female (43.2%) and 79 were male (56.8%), with a mean age of 51.82 ± 13.31 years. The prevalence of RLS was 15.8% (22 patients), with 50% of them (11 patients) having severe or very severe symptoms. There was a significant relationship between RLS and longer durations of dialysis (P < 0.001). The mean level of serum ferritin was lower in patients without RLS, but it was not significant (P = 0.065). No significant differences were found according to age, gender, dialysis shifts, and hemoglobin (Hb) level among patients with and without RLS.

Conclusions:

We conclude that a significant percentage of ESRD patients undergoing maintenance HD have severe or very severe RLS symptoms. The presence of RLS is associated to longer durations of dialysis.

Management of Restless Legs Syndrome/Willis-Ekbom Disease in Hospitalized and Perioperative Patients

Restless legs syndrome (RLS) is a sensorimotor disorder that can cause significant discomfort, impaired quality of life, poor mood, and disturbed sleep. Because the disorder is chronic and associated with multiple comorbidities, RLS can be seen in an inpatient or perioperative setting. Certain characteristics of the hospitalized or surgical context can exacerbate or unmask RLS. Importantly, RLS and the associated discomfort and insomnia can prolong hospital stay and negatively impact outcomes. RLS medications should be continued during the hospital admission when possible. Avoidance of excessive phlebotomy and medications known to trigger RLS is helpful. Patients should increase activity when acceptable.

The influence of parathyroidectomy on restless legs syndrome in patients with renal hyperparathyroidism

BACKGROUND

Restless legs syndrome (RLS) is a common and poorly understood movement disorder that leads to unpleasant leg sensations. Although RLS can be idiopathic, secondary etiologies such as iron deficiency and renal failure are common. The aim of this prospective cohort study was to evaluate whether RLS is a common feature in patients undergoing parathyroidectomy for renal hyperparathyroidism (rHPT) and if RLS-related symptoms can be influenced by surgery.

METHODS

After providing written consent, patients who underwent a parathyroidectomy for rHPT between January and November 2011 answered a validated RLS-screening-questionnaire (RLSSQ). If this was suggestive for RLS a confirming questionnaire (IRLS) was also completed on the day before surgery, on the fifth postoperative day, and again during follow-up (minimum 12 months). Perioperative parathyroid hormone and calcium levels, as well as the scores of the questionnaires were analyzed.

RESULTS

Twenty-one patients (14 men, 7 women) with a mean age of 47.8 ± 3.2 years underwent total parathyroidectomy with bilateral cervical thymectomy and parathyroid autotransplantation for rHPT. The mean score of the RLSSQ of all 21 patients prior to operation was 6.1 ± 0.5. In 10 of 21 patients (47.6 %) the results of the RLSSQ were suggestive for RLS with a mean score of 8.0 ± 0.3. The consecutive scores of the IRLS in these latter patients significantly dropped from 26.6 ± 1.4 to 19.0 ± 2.2 between the preoperative and postoperative settings (p < 0.05). After a mean follow-up of 17.3 ± 3.7 months the mean scores of the RLSSQ and the IRLS were 6.1 ± 0.6 and 16.3 ± 1.8.

CONCLUSIONS

rHPT may play a major role in the severity of RLS-associated symptoms in patients with renal failure. Consequently, parathyroidectomy may prove to be a valuable tool to reduce RLS-associated morbidity in affected patients. However, larger prospective trials are required to confirm the possible relation between RLS and rHPT seen in the present study

Restless legs syndrome in end stage renal disease patients on haemodialysis

Objective: This study was cross sectional survey conducted to find the prevalence of Restless legs syndrome (RLS) in end stage renal disease (ESRD) patients on haemodialysis (HD).

Methods: Data were obtained from 250 patients on chronic maintenance HD. To assess the prevalence of RLS, Clinical diagnostic criteria for RLS was used which is established by the International RLS Study Group.

Results: Total 250 patients were included in this study. 153 (61.2%) patients were male and 97 (38.8%) were females. Mean age of the patients was 45.27 years. Mean duration of HD was 26.10 months. Total162 (64.8%) patients were found to be suffering from RLS. Out of 153 males, 87(56%) were suffering from RLS and among 97 females, 75(77.3%) were suffering from RLS. In our study, gender was statistically significantly associated with RLS (p-value 0.001). In age groups 159(63.6%) patients were below 51 years; among them 102(64.1%) were suffering from RLS; whereas 91(36.4%) patients were equal or above 51 years of age and among this group 60(65.9%) patients were suffering from RLS. There was no statistically significant association between RLS and age groups (p-value 0.776).

Conclusions: RLS is common in patients undergoing regular HD. It is more commonly seen in females.

Restless legs syndrome in hemodialysis patients: an epidemiologic survey in Greece

BACKGROUND

Restless legs syndrome (RLS) is a sensorimotor disorder characterized by an uncontrolled need to move extremities accompanied by unpleasant sensations, which frequently leads to sleep disturbances. In hemodialysis (HD) patients, the previously reported RLS prevalence varied enormously, between 6% and 60%. In our study, we investigated the RLS prevalence in HD patients for the first time in Greece.

METHODS

A continuous sample of HD patients was studied between January and September of 2010 in six dialysis units in Greece. RLS diagnosis was based on the essential clinical criteria of the International RLS Study Group (IRLSSG). The standardized incidence ratio (SIR) for RLS in HD patients was calculated in comparison to data from a recent survey of the general population in Greece.

RESULTS

In our study of 579 HD patients in Greece (236 women; mean age, 65±13years), the prevalence of RLS was elevated in comparison to the general population (26.6% vs 3.9%), with an SIR of 5.4 (95% confidence interval [CI], 4.6-6.3). In the fully adjusted model, the risk for RLS in HD patients was reduced in older age (odds ratio [OR], 0.98 [95% CI, 0.96-0.99]) and increased in women (OR, 1.60 [95% CI, 1.05-2.43]) in cases with elevated levels of β2 microglobulin (OR, 1.15 [95% CI, 1.01-1.32]) and intact parathormone (iPTH) (OR, 1.30 [95% CI, 1.08-1.56]).

CONCLUSION

A high RLS prevalence was recorded in a large HD population in Greece, clearly suggesting the need for enhanced awareness of RLS in nephrology. The RLS risk was increased in women and in younger HD patients as well as in those with elevated β2 microglobulin and iPTH levels.

Effect of exercise training and dopamine agonists in patients with uremic restless legs syndrome: a six-month randomized, partially double-blind, placebo-controlled comparative study

Background

Restless Legs Syndrome is very common in hemodialysis patients however there are no comparative studies assessing the effectiveness of a non-pharmacological treatment to a classical treatment on parameters related to syndromes’ severity and quality of life.

Methods

In this randomized, partially double blind, placebo controlled trial, thirty two hemodialysis patients with restless legs syndrome were randomly assigned into three groups: 1) the exercise training group (N = 16), 2) the dopamine agonists group (ropinirole 0.25 mg/d) (N = 8) and 3) the placebo group (N = 8). The intervention programs lasted 6 months. Restless Legs Syndrome severity was assessed using the international severity scale, physical performance by a battery of tests, muscle size and composition by computed tomography, body composition by Dual Energy X Ray Absorptiometry, while depression score, sleep quality, daily sleepiness and quality of life were assessed through questionnaires.

Results

Exercise training and dopamine agonists were effective in reducing syndrome’s symptoms by 46% (P = 0.009) and 54% (P = 0.001) respectively. Within group changes revealed that both approaches significantly improved quality of life (P < 0.05), however, only the dopamine agonists significantly improved sleep quality (P = 0.009). Within group changes showed a tendency for lean body mass improvements with dopamine agonists, this reached statistical significance only with the exercise training (P = 0.014), which also reduced fat infiltration in muscles (P = 0.044) and improved physical performance (P > 0.05) in various tests. Between group changes detect significant improvements with both exercise and dopamine agonists in depression score (P = 0.003), while only the dopamine agonist treatment was able to significantly improve sleep quality, compared to exercise and placebo (P = 0.016).

Conclusions

A 6-month exercise training regime was as effective as a 6-month low dosage dopamine agonist treatment in reducing restless legs syndrome symptoms and improving depression score in uremic patients. Further research is needed in order to show whether a combination treatment could be more beneficial for the amelioration of RLS.

Trial registration

NCT00942253

Family recurrence and oligo-anuria predict uremic restless legs syndrome

OBJECTIVES

To determine clinical and laboratory predictors of restless legs syndrome (RLS) in patients with end-stage kidney disease (ESKD) undergoing long-term hemodialysis (HD).

MATERIALS AND METHODS

One hundred and sixty-two consecutive patients were assessed. History of sleep disturbances, neurological examination, clinical, and laboratory data were collected. Patients with and without RLS were compared, and a logistic regression model described the relations between independent predictors and RLS.

RESULTS

Fifty-one patients (32%) currently had RLS (RLS+). RLS+ vs RLS- patients were more frequently women (49% vs 29%, P = 0.012), had first-degree relative with RLS (22% vs 6%, P = 0.004), insomnia (59% vs 36%, P = 0.007), peripheral neuropathy (41% vs 21%, P = 0.006), and low residual diuresis (92% vs 68% with below 500 ml/24 h, P = 0.001). Low (OR = 8.71, CI = 2.27-33.41; P = 0.002) and absent (OR = 4.96, CI = 1.52-16.20; P = 0.008) residual diuresis, peripheral neuropathy (OR = 4.00, CI = 1.44-11.14; P = 0.008), and first-degree relative with RLS (OR = 3.82, CI = 1.21-12.13; P = 0.023) significantly predicted RLS in ESKD patients undergoing HD.

CONCLUSION

Positive family history for RLS together with reduced/absent residual renal function and peripheral neuropathy predicts the risk for RLS in ESKD patients undergoing HD. Longitudinal studies are warranted to correlate RLS occurrence with genetic and environmental factors.

Racial differences in restless legs symptoms and serum ferritin in an incident dialysis patient cohort

PURPOSE

Restless legs syndrome (RLS), a debilitating sleep disorder that is frequently reported by CKD patients on dialysis, may be more common in whites than in non-whites. Iron deficiency is associated with RLS, and serum ferritin is higher among African Americans compared to Caucasians in the general population. No prior studies have compared restless legs symptoms and serum ferritin levels of African-American and those of the Caucasian patients on dialysis.

METHODS

In a multicenter observational study that included in-person interviews and medical chart review, we studied 210 patients who had recently started renal dialysis. Predictors of restless legs symptoms were examined in a multivariable logistic regression model.

RESULTS

African Americans had a reduced risk of restless legs complaint compared to Caucasian patients (OR, 0.44 [95% CI 0.21-0.93]; P=0.03). African-American patients were also less likely than Caucasian patients to have low serum ferritin values (<100 ng/ml), and among patients with serum ferritin≥100 ng/ml, the average serum ferritin of African-American patients was higher than that of Caucasian patients.

CONCLUSIONS

Further study of racial and iron status relationships could advance the understanding of RLS pathophysiology, and RLS is an important patient outcome to monitor, as revised anemia and iron protocols are implemented in the clinical setting.

Sleep-related movement disorders

Several movement disorders may occur during nocturnal rest disrupting sleep. A part of these complaints is characterized by relatively simple, non-purposeful and usually stereotyped movements. The last version of the International Classification of Sleep Disorders includes these clinical conditions (i.e. restless legs syndrome, periodic limb movement disorder, sleep-related leg cramps, sleep-related bruxism and sleep-related rhythmic movement disorder) under the category entitled sleep-related movement disorders. Moreover, apparently physiological movements (e.g. alternating leg muscle activation and excessive hypnic fragmentary myoclonus) can show a high frequency and severity impairing sleep quality. Clinical and, in specific cases, neurophysiological assessments are required to detect the presence of nocturnal movement complaints. Patients reporting poor sleep due to these abnormal movements should undergo non-pharmacological or pharmacological treatments.

Restless legs syndrome: a comprehensive overview on its epidemiology, risk factors, and treatment

PURPOSES

Restless legs syndrome (RLS) is underdiagnosed and poorly understood by clinicians and the general public alike; accordingly, a broad literature review with information most relevant to general practice is needed to help dispel misconceptions and improve level of care.

METHODS

Specifically, this review comprehensively provides an epidemiological analysis of RLS and examines the risk factors and treatment options for RLS by compiling the findings of past RLS studies. These RLS studies were identified through a retrospective PubMed search. The epidemiological analysis was conducted by calculating a weighted mean average of all the relevant general population RLS prevalence studies, separated into geographical/racial categories.

RESULTS

A comprehensive analysis of RLS epidemiological studies finds the prevalence rate of RLS to be 5-15% in the general population with 2.5% of adults having symptoms severe enough to require medical intervention. Some of the risk factors for RLS include female gender, pregnancy, low iron levels, lower socioeconomic status, poor health, elderly age, comorbidity with Parkinson's disease, positive family history of RLS, and comorbidity with psychiatric disorders. A wide array of treatment options exist for RLS including pharmacological and nonpharmacologic interventions.

CONCLUSIONS

Clinicians' understanding of RLS enigma has recently improved due to the increased intensity of RLS research over the past decade. This review summarizes the current findings in the RLS field as well as providing guidelines for future RLS-related research.

Evidence of increased muscle atrophy and impaired quality of life parameters in patients with uremic restless legs syndrome

Background

Restless Legs Syndrome is a very common disorder in hemodialysis patients. Restless Legs Syndrome negatively affects quality of life; however it is not clear whether this is due to mental or physical parameters and whether an association exists between the syndrome and parameters affecting survival.

Methodοlogy/Principal Findings

Using the Restless Legs Syndrome criteria and the presence of Periodic Limb Movements in Sleep (PLMS/h >15), 70 clinically stable hemodialysis patients were assessed and divided into the RLS (n = 30) and non-RLS (n = 40) groups. Physical performance was evaluated by a battery of tests: body composition by dual energy X ray absorptiometry, muscle size and composition by computer tomography, while depression symptoms, perception of sleep quality and quality of life were assessed through validated questionnaires. In this cross sectional analysis, the RLS group showed evidence of thigh muscle atrophy compared to the non-RLS group. Sleep quality and depression score were found to be significantly impaired in the RLS group. The mental component of the quality of life questionnaire appeared significantly diminished in the RLS group, reducing thus the overall quality of life score. In contrast, there were no significant differences between groups in any of the physical performance tests, body and muscle composition.

Conclusions

The low level of quality of life reported by the HD patients with Restless Legs Syndrome seems to be due mainly to mental health and sleep related aspects. Increased evidence of muscle atrophy is also observed in the RLS group and possibly can be attributed to the lack of restorative sleep.

Measurement invariance of the kidney disease and quality of life instrument (KDQOL-SF) across veterans and non-veterans

BACKGROUND

Studies have demonstrated that perceived health-related quality of life (HRQOL) of patients receiving hemodialysis is significantly impaired. Since HRQOL outcome data are often used to compare groups to determine health care effectiveness it is imperative that measures of HRQOL are valid. However, valid HRQOL comparisons between groups can only be made if instrument invariance is demonstrated. The Kidney Disease Quality of Life-Short Form (KDQOL-SF) is a widely used HRQOL measure for patients with chronic kidney disease (CKD) however, it has not been validated in the Veteran population. Therefore, the purpose of this study was to examine the measurement invariance of the KDQOL-SF across Veterans and non-Veterans with CKD.

METHODS

Data for this study were from two large prospective observational studies of patients receiving hemodialysis: 1) Veteran End-Stage Renal Disease Study (VETERAN) (N = 314) and 2) Dialysis Outcomes and Practice Patterns Study (DOPPS) (N = 3,300). Health-related quality of life was measured with the KDQOL-SF, which consists of the SF-36 and the Kidney Disease Component Summary (KDCS). Single-group confirmatory factor analysis was used to evaluate the goodness-of-fit of the hypothesized measurement model for responses to the subscales of the KDCS and SF-36 instruments when analyzed together; and given acceptable goodness-of-fit in each group, multigroup CFA was used to compare the structure of this factor model in the two samples. Pattern of factor loadings (configural invariance), the magnitude of factor loadings (metric invariance), and the magnitude of item intercepts (scalar invariance) were assessed as well as the degree to which factors have the same variances, covariances, and means across groups (structural invariance).

RESULTS

CFA demonstrated that the hypothesized two-factor model (KDCS and SF-36) fit the data of both the Veteran and DOPPS samples well, supporting configural invariance. Multigroup CFA results concerning metric and scalar invariance suggested partial strict invariance for the SF-36, but only weak invariance for the KDCS. Structural invariance was not supported.

CONCLUSIONS

Results suggest that Veterans may interpret the KDQOL-SF differently than non-Veterans. Further evaluation of measurement invariance of the KDQOL-SF between Veterans and non-Veterans is needed using large, randomly selected samples before comparisons between these two groups using the KDQOL-SF can be done reliably.

Restless legs syndrome in end-stage renal disease: Clinical characteristics and associated comorbidities

BACKGROUND

Despite being frequently described in patients with end-stage renal disease (ESRD), clinical characteristics and comorbidities in association with restless legs syndrome (RLS) are still to be confirmed.

OBJECTIVES

The aim of this study was to investigate clinical factors associated with RLS in ESRD patients in hemodialysis.

METHODS

This is a cross-sectional study of 400 patients on hemodialysis, evaluating RLS, clinical features and other sleep abnormalities.

RESULTS

Out of 400, 86 patients presented RLS (21.5%; mean age 48.8+/-13.8y), being more frequent in females (p<0.005). Forty-eight individuals (12% mean age 50.7+/-13.1y) had moderate/severe RLS, 14 reported symptoms prior to hemodialysis, 13 described family history of RLS, and eight described symptoms as disturbing during dialysis. RLS cases showed lower hemoglobin (p<0.005), poorer quality of sleep (Pittsburgh Sleep Quality Index >5, p=0.002), higher scores on the Beck Depression Inventory Scale (p<0.005), greater scores on the Charlson Comorbidity Index (p=0.01) and the Epworth Sleepiness Scale (p=0.001) and higher risk of obstructive sleep apnea (OSA; Berlin questionnaire, p=0.01). Hypertension was more frequent in cases with moderate/severe RLS (p=0.01) and remained after controlling for the risk of OSA (p=0.02).

CONCLUSION

In ESRD patients in hemodialysis, RLS is present in 21.5%; 16% report symptoms prior to hemodialysis and a family history of RLS. Symptoms are disturbing during hemodialysis in 9% of cases. RLS is associated with lower hemoglobin, worse sleep quality, excessive daytime sleepiness, depressive symptoms and higher risk of OSA. Hypertension is associated with moderate/severe RLS.

Effects of restless legs syndrome on quality of life and psychological status in patients with type 2 diabetes

PURPOSE

The purpose of this study was to evaluate the effects of restless legs syndrome (RLS) on quality of life (QoL), anxiety, and depression in people with type 2 diabetes.

METHODS

One hundred twenty-four patients with type 2 diabetes were enrolled in this study. RLS was diagnosed by a neurologist masked on psychological evaluation. Data on severity, frequency, and duration of the sleep disorder were collected. The Italian version of the SF-36 was used to assess QoL. Psychological status was investigated by a neuropsychologist masked on RLS diagnosis. Patients with a diagnosis of generalized anxiety disorder (GAD) and major depressive disorder (MDD) were considered affected by anxiety and depression, respectively. A modified version of the Hamilton Anxiety and Depression Rating Scales (HARS and HDRS) was also administered.

RESULTS

RLS was an independent predictor for several mental domains of the SF-36 and for the mental component summary. Multivariate analysis showed that RLS was an independent predictor of anxiety and depression. RLS severity correlated with HARS and HDRS scores, whereas frequency per week of RLS had a significant correlation only with HARS score.

CONCLUSIONS

Among individuals with diabetes, RLS can impair mental health, increasing the risk for anxiety and depression. Since RLS consequences on nocturnal rest and psychological status may impair glycemic control in this population, diabetologists and diabetes educators should investigate for the presence of RLS in their patients and treat them.

Sleep disorders and home dialysis

Sleep disorders, such as restless legs, periodic limb movements and sleep apnea, and sleep complaints such as insomnia and daytime sleepiness, are very common in end-stage renal disease patients despite treatment with 3-times-a-week conventional hemodialysis. If left untreated, they are likely to impair quality of life and may alter cardiovascular outcomes in this patient population. Home dialysis has the potential to improve sleep disorders by offering more effective dialysis than conventional modalities. Although there has been little direct comparison between the impact of home dialysis and conventional dialysis on sleep disorders, there is evidence that both nocturnal peritoneal dialysis and nocturnal hemodialysis improve sleep apnea. The impact of home dialysis on other sleep disorders and sleep complaints is less impressive, but the data, thus far, have been limited. Further research is required to evaluate the impact of home dialysis on all sleep disorders and sleep complaints in this patient population and to determine whether this improves quality of life and cardiovascular morbidity and mortality.

Restless legs syndrome in patients on hemodialysis: symptom severity and risk factors

Background and Purpose

Restless legs syndrome (RLS) is a sleep disorder that frequently occurs in dialysis patients, which disturbs the sleep and reduces the quality of life. The aim of this study was to determine the risk factors for RLS in dialysis patients.

Methods

Patients who visited any of four outpatient dialysis clinics between September 2005 and May 2006 were included in this study. The diagnosis of RLS and the severity assessment were made using the criteria described by the International Restless Legs Syndrome Study Group. We collected basic demographic data, clinical information, and laboratory findings, and then analyzed their association with various aspects of RLS using univariate and multivariate analyses.

Results

RLS was present in 46 (28.0%) of 164 dialysis patients. We found no significant risk factor for inducing RLS. The predialysis serum blood urea nitrogen (BUN) level in the dialysis patients with RLS was significantly correlated with RLS symptom severity.

Conclusions

Predialysis BUN is related to RLS symptom severity. Further studies on the underlying mechanism are needed.

Clinical characteristics of restless legs syndrome in end-stage renal failure and idiopathic RLS patients

This study was done to identify the clinical characteristics of uremic restless legs syndrome (RLS). Consecutive uremic RLS patients (n = 15) and idiopathic RLS patients (iRLS; n = 20) were evaluated. The groups were compared with respect to their clinical course, subjective symptoms [using the Pittsburgh Sleep Quality Index (PSQI) and the International Restless Legs Syndrome Severity Scale (IRLS)], polysomnographic (PSG) variables, the results of the suggested immobilization test (SIT), and the drug doses used to treat RLS. The duration of the disorder was significantly shorter in the uremic RLS group than in the iRLS group. The PSQI and IRLS scores before treatment were higher in the uremic RLS group than in the iRLS group. The periodic leg movement index (PLM index) on PSG and the SIT index were also higher in the uremic RLS group (P < 0.001, respectively). The bromocriptine equivalent dose of dopaminergic agonists used to treat RLS was significantly higher in the uremic RLS group (P < 0.001). Uremic RLS appears to deteriorate faster and to become more severe than iRLS. Moreover, uremic RLS patients appear to have a decreased response to dopaminergic agonists.

Impact of spiritual and religious activity on quality of sleep in hemodialysis patients

BACKGROUND

Sleep disorders are common in hemodialysis (HD) patients. This study examined the relationship between quality of sleep (QoS) and religious/spiritual activity in HD patients.

METHODS

The study subjects were 861 HD patients from 14 dialysis clinics in Taiwan. QoS and religious/spiritual activity were evaluated by the Pittsburgh Sleep Quality Index (PSQI) questionnaire and the Royal Free Questionnaire respectively.

RESULTS

There was no difference in clinical parameters between the good and poor sleepers. Although total scores of religious and spiritual activity did not correlate with global PSQI score, patients who held strong 'spiritual' beliefs reported more problems in 'sleep disturbances', while those who exercised religious beliefs more strongly reported less trouble in 'daytime dysfunction'.

CONCLUSION

There is no significant correlation between QoS and religious/spiritual activity globally. However, the spiritual and religious activity did associate with different components of QoS.