Restless legs syndrome--theoretical roles of inflammatory and immune mechanisms

Evaluation of upper endoscopic findings in patients with restless legs syndrome and gastric complaints

BACKGROUND

The effect of gastrointestinal system disorders on Restless Legs Syndrome/Willis-Ekbom disease (RLS/WED) has been previously demonstrated by using serological tests. However, this association has not been supported by histopathological studies so far.

OBJECTIVE

To investigate the relationship between RLS/WED, upper endoscopic imaging and histopathological results in patients diagnosed with RLS who underwent endoscopy because of gastrointestinal system (GIS) complaints.

METHODS

Case-control study, including 100 patients diagnosed with RLS who presented dyspeptic complaints and underwent upper GIS endoscopy and 106 age- and sex-matched controls. RLS diagnosis was evaluated according to the four main diagnostic criteria determined by the International RLS Study Group. All patients underwent upper GIS endoscopic intervention and at least one gastric and/or antral biopsy.

RESULTS

There was no significant difference between patients and controls in relation to endoscopically seen gastric ulcer, duodenal ulcer, gastroesophageal reflux disease (GERD) findings and Helicobacter pylori (HP) positivity (p>0.05). Intestinal metaplasia and mucosal atrophy were more common in RLS/WED patients compared to controls (p=0.026 and p=0.017, respectively). Additionally, ferritin levels were found to be lower than the reference value.

CONCLUSIONS

The detection of increased severity of intestinal metaplasia, mucosal atrophy, and gastric inflammation in RLS/WED patients with dyspeptic complaints may entail the close gastrointestinal system evaluation of these patients. However, larger randomized and controlled trials are required on this subject where patients are evaluated by upper GIS endoscopic biopsy.

Does restless legs syndrome impact cognitive function via sleep quality in adults with Parkinson's disease?

Purpose: Restless legs syndrome (RLS) is a sleep disorder that results in sleep dysfunction. Sleep disruption can have profound negative consequences in adults with Parkinson's disease (PD), potentially including cognitive dysfunction. This study examined the relationships among RLS, cognition, and sleep quality in persons with PD.Materials and methods: Participants (N = 79) with idiopathic PD completed six questionnaires evaluating RLS, sleep quality, daytime sleepiness, global cognitive function, sleep apnea risk, and depression. Participants were further examined for body mass index composition and motor symptom severity (MDS-UPDRS Part III).Results: Persons with RLS (n = 25) had significantly worse cognitive function (p = 0.035, d = -0.56) and sleep quality (p < 0.0001, d = -1.19), and more daytime sleepiness (p = 0.009, d = 0.67) than those without RLS (n = 54). Cognitive function was not significantly correlated with sleep quality (rs = 0.113) or daytime sleepiness (rs = -0.001). The association between RLS and cognition was not attenuated by controlling for sleep quality or daytime sleepiness.Conclusions: This study is unique as it is the first to consider the possibility that RLS in PD may be associated with cognitive deficits through a pathway involving sleep quality. Persons with RLS and PD have greater deficits in both sleep quality and cognitive function than individuals without RLS; however, cognitive dysfunction among those with PD and RLS in this sample is not accounted for by sleep quality.

The prevalence of insomnia and restless legs syndrome among Japanese outpatients with rheumatic disease: A cross-sectional study

The prevalence of symptomatic insomnia and the prevalence of restless legs syndrome (RLS) are known to be higher among patients with rheumatic diseases compared to the general population. The prevalences of insomnia and RLS reported in a questionnaire by Japanese patients with rheumatic diseases at an outpatient clinic were analyzed herein. The association between the patients' disease activity and their sleep quality was analyzed. Of 121 rheumatic disease patients, 70 were enrolled. The median (interquartile range) age at enrollment was 62.0 (47.8-68.0) years. There were 58 women (82.9%) and 12 men (17.1%), and 43 patients (61.4%) with rheumatoid arthritis (RA), nine (12.9%) with systemic lupus erythematosus (SLE), and 18 (25.7%) with other rheumatic diseases. Twenty patients (28.6%) had one or more moderate-to-severe insomnia symptoms, and 10 (14.3%) were diagnosed with RLS. Among the patients with RA, the swollen joint count based on a 28-joint assessment (SJC28) was significantly higher in the insomnia group (n = 13) compared to the non-insomnia group (n = 30) (p = 0.006). A classification and regression tree (CART) analysis showed that the cut-off points of ≥3 mg/day prednisolone (PSL) treatment and <16.54% as the transferrin saturation (TSAT) value would best predict RLS in rheumatic disease. Patients with rheumatic disease had a high prevalence of symptomatic insomnia and RLS. A higher dose of PSL and lower TSAT were associated with the occurrence of RLS.

Restless legs syndrome is associated with mast cell activation syndrome

STUDY OBJECTIVES

Mast cell activation syndrome (MCAS) is an inflammatory and allergic disorder. We determined the prevalence of restless legs syndrome (RLS) in MCAS because each common syndrome may be inflammatory in nature and associated with dysautonomia.

METHODS

Individuals with MCAS were evaluated for RLS by two standard questionnaires. Prevalence comparisons included spouse control patients and two prevalence publications. MCAS diagnosis required mast cell (MC) symptoms in ≥ 2 organs plus ≥ 1 elevated MC mediators, improvement with MC therapy, and/or increased intestinal MC density. Clinical variables were studied.

RESULTS

There were 174 patients with MCAS (146 female, 28 male, mean age 44.8 years) and 85 spouse control patients (12 female, 73 male, mean age 50.9 years). Patients with MCAS as a whole had a higher prevalence of RLS (40.8%) than spouse control (12.9%) (P < .0001) Male patients with MCAS had a higher prevalence of RLS (32.1%) than male controls (12.3%, odds ratio [OR] 3.4, confidence interval [CI] 1.2-9.7, P = .025), American men (8.4%, OR 5.2, CI 2.2-12.0, P < .001), and French men (5.8%, OR 7.7, CI 3.4-17.1, P < .001). Female patients with MCAS also had a higher prevalence of RLS (42.5%) than female controls (16.7%) but this did not reach statistical significance perhaps because of the sample size of the female controls. However, female patients with MCAS had a statistically higher prevalence of RLS than American women (10.0%, OR 6.7, CI 4.5-9.7, P < .0001) and French women (10.8%, OR 6.1, CI 4.4-8.6, P < .0001).

CONCLUSIONS

RLS appears to be associated with MCAS. Effects of mast cell mediators, inflammation, immune mechanisms, dysautonomia, or hypoxia may theoretically activate RLS in MCAS.

Evaluation of restless legs syndrome and sleep disorders in patients with psoriatic arthritis

OBJECTIVES

Restless legs syndrome (RLS) is a neurological disease with a chronic course that is characterised by sleep disorders and sensorimotor impairment. The aim of this study was to evaluate the prevalence and severity of RLS in psoriatic arthritis (PSA) patients and those with psoriasis (P).

PATIENTS AND METHODS

The study included 50 patients with psoriasis (28 females, 22 males), 50 PSA patients (33 females, 17 males) and 50 healthy control subjects (34 females, 16 males), and all 3 groups were matched with respect to age, gender and body mass index (BMI). Evaluations were made using the International RLS Rating Scale, Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale, Insomnia Severity Index, Fatigue Severity Scale (FSS), Beck Depression Index (BDI) and the SF-36 quality of life scores.

RESULTS

RLS was determined at a higher rate in the PSA patients (64.0%), compared to the P group (20.0%, p < 0.001) and the control group (14.0%, p < 0.001). The number of moderate and severe RLS cases was significantly higher in the PSA group (68.7%) compared to the P group (30%, p < 0.001) and the control group (0%, p < 0.001). In regression analysis, an independent correlation was found between the RLS score and PSQI (beta [β] = 0.269, p = 0.002), FSS (β = 0.243, p = 0.003), SF-36 physical score (β = 0.242, p = 0.004) and BDI (β = 0.177, p = 0.036).

CONCLUSION

RLS was determined in PSA patients at a higher rate than in psoriasis patients. The presence of RLS in PSA and psoriasis patients is related to impairments in sleep and quality of life, fatigue and depression.

Restless Legs Syndrome in Chronic Kidney Disease: Is Iron or Inflammatory Status To Blame?

STUDY OBJECTIVES

Restless legs syndrome (RLS) is increased in pediatric chronic kidney disease (CKD). In adults without CKD, central nervous system iron deficiency is involved in RLS pathogenesis and a low serum ferritin levels is consequently an indication for initiation of iron therapy. However, children with CKD are at risk for iron deficiency and inflammation, which raises serum ferritin. We examined the role of iron deficiency and inflammation in RLS in pediatric CKD.

METHODS

This cross-sectional study examined RLS prevalence in three groups of pediatric patients with CKD: nontransplant, nondialysis CKD (estimated GFR < 60 mL/min/1.73 m²) (n = 27); renal transplant recipients (n = 65); and dialysis (n = 32). RLS was diagnosed using a validated questionnaire. Serum ferritin < 100 ng/mL or transferrin saturation < 20% defined iron deficiency. Serum high sensitivity C-reactive protein ≥ 1 mg/L defined inflammation.

RESULTS

Among 124 patients, RLS prevalence was 15.3%; this did not differ across groups. There was no significant difference in RLS prevalence between those with and without iron deficiency, defined by either reduced ferritin or transferrin. Median ferritin levels in patients with RLS tended to be higher than in those without RLS (51.2 versus 40.1 ng/mL; P = .08). Inflammation (elevated CRP) also did not differ significantly by RLS status (57.9% [with RLS] versus 41.2% [without RLS], P = .18).

CONCLUSIONS

Neither ferritin nor inflammation differentiated pediatric patients with CKD with and without RLS. This study suggests that the factors mediating the pathogenesis and, potentially, treatment, of RLS in pediatric CKD may be different from non-CKD populations.

Blood pressure profile and endothelial function in restless legs syndrome

Restless legs syndrome (RLS) is frequently comorbid with hypertension and cardiovascular diseases; however this relationship and underlying mechanisms remain controversial. After clinical evaluation, 84 drug-free patients with primary RLS (53 women; mean age 55.1 ± 12.3 years) and 76 controls (47 women; mean age 52.2 ± 15.3 years) underwent 24-hour ambulatory blood pressure (BP) and polysomnographic monitoring, and peripheral arterial tonometry to assess endothelial function for 61 patients and 69 controls. Hypertension was diagnosed in 11.9% of patients with RLS based on office measurement, and in 46.4% on the 24 h recording, with nighttime hypertension, two times more frequent than daytime hypertension. Periodic limb movement during sleep (PLMS), markers of sleep fragmentation, and systolic and mean BP non-dipping profile were more frequent among patients. BP non-dipping status was associated with older age, later RLS onset and diagnosis, RLS severity and higher sleep fragmentation. The mean 24-hour, daytime and nighttime BP values, the frequency of hypertension and the endothelial function were comparable between groups. However, both systolic and diastolic BP trajectories over a 24-hour period differed between groups. In conclusion, patients with RLS exhibit a 24-hour BP deregulation with increased frequency of systolic non-dipping profiles that could worsen the risk for CVD morbidity and mortality.

Use of antidepressants and risks of restless legs syndrome in patients with irritable bowel syndrome: A population-based cohort study

Previous research has suggested an association between antidepressants use and clinical restless legs syndrome (RLS) in patients, but there has never been a single study investigating the risk of RLS in irritable bowel syndrome (IBS) patients treated with antidepressants. Hence, we aimed to explore the association between IBS and RLS and to examine the risk of RLS in IBS patients treated with antidepressants. With the use of the National Health Insurance Research Database of Taiwan, 27,437 adults aged ≥ 20 years with newly diagnosed IBS (ICD-9-CM Code 564.1) and gender- and age-matched 54,874 controls without IBS were enrolled between 2000 and 2012. All patients were followed-up until RLS diagnosis, withdrawal from the National Health Insurance program, or end of 2013. We used the Cox proportional hazards model to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs) of RLS. RLS was more prevalent in IBS patients than in the non-IBS group (7.57 versus 3.36 per 10,000 person-years), with an increased risk of RLS (adjusted HR [aHR], 1.91; 95% CI, 1.52-2.40). Multivariate Cox proportional hazards analysis identified older age (age, 51-65 years; aHR, 1.67; 95% CI, 1.09-2.56; and age > 65; aHR, 1.59; 95% CI, 1.02-2.48), hypothyroidism (aHR, 4.24; 95% CI, 1.92-9.37), CAD (aHR, 1.70; 95% CI, 1.17-2.48), and depression (aHR, 3.15; 95% CI, 2.14-4.64) as independent RLS risk factors in IBS patients. In addition, the male SSRIs users were associated with significantly higher risk of RLS (aHR, 3.05 95% CI, 1.34-6.92). Our study showed that the IBS group has higher risk of RLS. Moreover, SSRIs use may increase the risk of RLS in male IBS patients.

Post-polio Syndrome: More Than Just a Lower Motor Neuron Disease

Post-polio syndrome (PPS) is a neurological condition that affects polio survivors decades after their initial infection. Despite its high prevalence, the etiology of PPS remains elusive, mechanisms of progression are poorly understood, and the condition is notoriously under-researched. While motor dysfunction is a hallmark feature of the condition, generalized fatigue, sleep disturbance, decreased endurance, neuropsychological deficits, sensory symptoms, and chronic pain are also often reported and have considerable quality of life implications in PPS. The non-motor aspects of PPS are particularly challenging to evaluate, quantify, and treat. Generalized fatigue is one of the most distressing symptoms of PPS and is likely to be multifactorial due to weight-gain, respiratory compromise, poor sleep, and polypharmacy. No validated diagnostic, monitoring, or prognostic markers have been developed in PPS to date and the mainstay of therapy centers on symptomatic relief and individualized rehabilitation strategies such as energy conservation and muscle strengthening exercise regimes. Despite a number of large clinical trials in PPS, no effective disease-modifying pharmacological treatments are currently available.

Increased frequency of the restless legs syndrome in adults with cystic fibrosis

BACKGROUND

Patients with cystic fibrosis (CF) may suffer from iron deficiency which is a known risk factor for the restless legs syndrome (RLS), however, its prevalence has not yet been investigated in these subjects.

PATIENTS AND METHODS

Adult out-patients with CF (n = 39) and healthy volunteers (n = 32) were recruited for this study. A diagnosis of RLS was made based on the diagnostic criteria established by the International Restless Legs Syndrome Study Group (IRLSSG). The IRLSSG rating scale was used to assess the severity of the disease. Furthermore, in the CF group, parameters of iron metabolism were measured in peripheral venous blood samples.

RESULTS

The RLS occurred more frequently in the CF patients than the controls (n = 13/33,3% vs. n = 2/6,3%; p < 0,05). In the CF patients suffering from RLS, the mean score of the IRLSSG rating scale was 17,2 ± 9,4 indicating moderate disease severity. Iron deficiency was present in the majority of the CF patients investigated (n = 33/84,6%), however, serum iron, ferritin and transferrin levels as well as transferrin saturation were similar in those with vs. without RLS.

CONCLUSIONS

The frequency of the RLS is increased in adult patients with CF. On an average, its severity is moderate and it is not related to iron deficiency as evaluated by serum parameters of iron metabolism.

Serum C-reactive protein/albumin ratio and restless legs syndrome

OBJECTIVES

Our study aimed to assess the variation in serum C-reactive protein/albumin ratio (CAR), a biomarker of peripheral inflammation and oxidative stress, in patients with restless legs syndrome (RLS).

METHODS

The study included a total of 380 individuals including 197 with RLS diagnosis. RLS diagnosis was determined according to the "International Restless Legs Syndrome Study Group" questionnaire. Disease severity was assessed according to the "International Restless Legs Syndrome Study Group Severity Scale''.

RESULTS

The mean age of patients with restless legs syndrome was 52.5 ± 12.7 years, while the mean age in the control group was 50.8 ± 11.2, with no statistically significant difference found (p = 0.156). The hemoglobin, iron and ferritin levels in the patient group were lower than in the control group (p < 0.001; p < 0.01; p < 0.001), with total iron binding capacity levels higher than the control group (p < 0.001). The mean ferritin in the RLS group (49.8 ± 51.2) was lower than the control group (76.9 ± 44.7). In patients, the c-reactive protein, albumin and c-reactive protein/albumin ratio were found to be 0.21 ± 0.18, 4.43 ± 0.31 and 0.07 ± 0.05, respectively. When compared with the control group, the patient group had high c-reactive protein (CRP), CAR and low albumin levels (p < 0.001). Among patients with "very severe" disease severity, ferritin levels were found to be lower than those with "moderate" disease severity. Additionally, patients with "very severe" disease had albumin levels which were significantly low compared to those with "mild" disease severity (p < 0.05).

CONCLUSION

Our study supports the hypothesis that serum albumin level, ferritin, CRP, and CAR may be associated with restless legs syndrome.

Potential Role for the Gut Microbiota in Modulating Host Circadian Rhythms and Metabolic Health

This article reviews the current evidence associating gut microbiota with factors that impact host circadian-metabolic axis, such as light/dark cycles, sleep/wake cycles, diet, and eating patterns. We examine how gut bacteria possess their own daily rhythmicity in terms of composition, their localization to intestinal niches, and functions. We review evidence that gut bacteria modulate host rhythms via microbial metabolites such as butyrate, polyphenolic derivatives, vitamins, and amines. Lifestyle stressors such as altered sleep and eating patterns that may disturb the host circadian system also influence the gut microbiome. The consequent disruptions to microbiota-mediated functions such as decreased conjugation of bile acids or increased production of hydrogen sulfide and the resultant decreased production of butyrate, in turn affect substrate oxidation and energy regulation in the host. Thus, disturbances in microbiome rhythms may at least partially contribute to an increased risk of obesity and metabolic syndrome associated with insufficient sleep and circadian misalignment. Good sleep and a healthy diet appear to be essential for maintaining gut microbial balance. Manipulating daily rhythms of gut microbial abundance and activity may therefore hold promise for a chrononutrition-based approach to consolidate host circadian rhythms and metabolic homeorhesis.

A study for the mechanism of sensory disorder in restless legs syndrome based on magnetoencephalography

In spite of the relatively high incidence rate, the etiology and pathogenesis of restless legs syndrome (RLS) are still unclear. Long-term drug treatments fail to achieve satisfying curative effects, which is reflected by rebound and augmentation of related symptoms. An electrophysiological endophenotype experiment was done to investigate the mechanism of somatosensory disorder among RLS patients. Together with 15 normal subjects as the control group, with comparable ages and genders to the RLS patients, 15 primitive RLS patients were scanned by Magnetoencephalography (MEG) under natural conditions; furthermore, the somatosensory evoked magnetic field (SEF) with single and paired stimuli, was also measured. Compared to the control group, the SEF intensities of RLS patients' lower limbs were higher, and the paired-pulse depression (PPD) for SEF in RLS patients was attenuated. It was also revealed by time-frequency analysis of somatosensory induced oscillation (SIO) in RLS patients, that 93.3% of somatosensory induced Alpha (8-12 Hz) oscillations were successfully elicited, while 0% somatosensory induced Gamma (30-55 Hz) oscillations were elicited; which was significantly different from the control group. Additionally, in RLS patients exhibit increased excitability of the sensorimotor cortex, a remarkable abnormality existing in early somatosensory gating control (GC) and an attenuated inhibitory interneuron network, which consequently results in a compensatory mechanism through which RLS patients increase their attention-driven lower limb sensory gating control via somatosensory-induced Alpha (8-12 Hz) oscillation. This hyperexcitability, partially due to an electrocortical disinhibition, may have an important therapeutical implication, and become an important target of neuromodulatory interventions.

Discovery of restless legs syndrome plasmatic biomarkers by proteomic analysis

OBJECTIVES

Restless legs syndrome (RLS) can lead to severe clinical consequences, thus negatively impacts on patients' overall health and quality of life. Nevertheless, the pathophysiology of RLS is still unclear, resulting in underestimate, incorrect, or ignored diagnosis and in limited management and treatment. The aim of this study was to compare the plasma proteome of RLS patients and healthy controls, in the search of diagnostic biomarkers related to the disease severity.

MATERIALS AND METHODS

Two-dimensional gel electrophoresis coupled with liquid chromatography-mass spectrometry was employed to analyze plasma samples of 34 patients with primary RLS, divided into two subgroups according to the disease severity: MMS group (mild-moderate symptoms) and HS group (severe and very severe symptoms), and 17 age- and sex-matched control subjects. Sleep quality, daytime sleepiness, and the level of depression were also evaluated.

RESULTS

We identified eight upregulated spots, corresponding to five unique proteins, in both RLS group vs. controls (alpha-1B-glycoprotein, alpha-1-acid glycoprotein 1, haptoglobin, complement C4-A, and immunoglobulin kappa constant); five increased spots, consistent with three unique proteins, only in HS-RLS (kininogen-1, immunoglobulin heavy constant alpha 1, and immunoglobulin lambda constant 2); one downregulated spot in both patient's groups (complement C3) and another one only in HS-RLS (alpha-1-antitrypsin).

CONCLUSIONS

The significantly different plasma proteins detected in RLS were mainly associated with inflammation, immune response, and cardiovascular disorders. Particularly, the gradual increasing in immunoglobulins could be indicative of the disease severity and evolution. Accordingly, these proteins may represent a valid set of useful biomarkers for RLS diagnosis, progression and treatment.

Mast cell deposition and activation may be a new explanation for epiploic appendagitis

Epiploic appendagitis is as an acute painful condition of the fat on the outside of the intestine. Thus far, there have been no publications to our knowledge that appendagitis can be caused by mast cells or can be associated with chronic pain. A patient with multisystemic disorders suffered with both chronic and acute attacks of abdominal pain for a year. The worst attack led to surgical resection of an enlarged sigmoid colon epiploic appendage. Careful review of her complex medical history and mast cell stains of gastrointestinal biopsies led to the diagnosis of mast cell activation syndrome. Re-examination of the resected appendage using an immunohistochemical stain demonstrated a high mast cell density which is a new histopathological finding. Treatment of mast cell activation syndrome and other related syndromes led to marked improvement in her health, including all types of chronic abdominal pain.

Restless legs syndrome in children with allergic rhinitis: A comparative study on frequency, severity and sleep quality

OBJECTIVES

This study aims to investigate the frequency and severity of restless legs syndrome (RLS) and its relationship with sleep quality in children with allergic rhinitis (AR) with the hypothesis that comorbid RLS may be an additional causative factor of sleep disturbances in pediatric AR.

PATIENTS AND METHODS

A total of 143 children with AR (aged 8-18 years) and 144 healthy control subjects (aged 8-18 years) were included. The diagnosis of AR was established on history, clinical examination and skin prick test according to the Allergic Rhinitis and its Impact on Asthma guidelines. Presence of RLS was determined using the International RLS study group (IRLSSG) criteria. The severity of RLS was assessed using the IRLSSG rating scale. Sleep quality was evaluated by Pittsburgh Sleep Quality Index (PSQI).

RESULTS

Thirteen patients (9.1%) in AR group, and six children (4.2%) in control group had RLS (p=0.159). The frequency of RLS in AR group was higher than two folds when compared to the control group; however, the difference was not statistically significant. Restless legs syndrome severity score was significantly higher in AR group than control group (15.00 [11-20] and 11.00 [10-16] respectively, p=0.046). Total PSQI scores were similar between groups. Also, no significant differences were observed in total PSQI scores of AR patients with or without RLS.

CONCLUSION

Restless legs syndrome was not more common but was more severe in children with AR. There was no evidence that RLS has an obvious effect on sleep quality in children with AR.

Restless Legs Syndrome and Sleep-Related Movement Disorders

PURPOSE OF REVIEW

This article provides an update on six sleep-related movement disorders: restless legs syndrome (RLS), periodic limb movement disorder, sleep-related leg cramps, bruxism, rhythmic movement disorder, and propriospinal myoclonus, with an emphasis on RLS.

RECENT FINDINGS

RLS is a common sensorimotor disorder that impairs quality of life. RLS is frequently comorbid to neurologic, psychiatric, vascular, and inflammatory diseases. Accumulating evidence implicates the pathophysiology of RLS as a state of dopamine dysfunction and iron deficiency that occurs on a background of genetic susceptibility conferred by 6 gene polymorphisms. Multiple treatments approved by the US Food and Drug Administration (FDA) are available. Dopamine agonists and α2δ calcium channel ligands are considered first-line treatments, but these treatments have very different side effect profiles that should be taken into consideration.

SUMMARY

Sleep-related movement disorders are frequently encountered in clinical practice. For some disorders, particularly RLS and periodic limb movement disorder, our understanding of biology, epidemiology, and treatment is advanced. For others, much work is needed to determine optimal treatment strategies.

Hepcidin, an emerging and important player in brain iron homeostasis

Hepcidin is emerging as a new important factor in brain iron homeostasis. Studies suggest that there are two sources of hepcidin in the brain; one is local and the other comes from the circulation. Little is known about the molecular mediators of local hepcidin expression, but inflammation and iron-load have been shown to induce hepcidin expression in the brain. The most important source of hepcidin in the brain are glial cells. Role of hepcidin in brain functions has been observed during neuronal iron-load and brain hemorrhage, where secretion of abundant hepcidin is related with the severity of brain damage. This damage can be reversed by blocking systemic and local hepcidin secretion. Studies have yet to unveil its role in other brain conditions, but the rationale exists, since these conditions are characterized by overexpression of the factors that stimulate brain hepcidin expression, such as inflammation, hypoxia and iron-overload.

Severity and frequency of restless legs syndrome in patients with familial Mediterranean fever

Objective:

Restless legs syndrome (RLS) is a common sensory motor disorder. RLS an urge to move the extremities that may be accompanied by dysesthesias, and significantly affects quality of life of affected patients. The frequency of RLS is higher in different systemic inflammatory diseases. Familial Mediterranean fever (FMF) is an inherited inflammatory disease characterized by attacks of polyserositis, arthritis, and fever. The prevalence of RLS in patients with FMF is unknown. This study aimed to evaluate the prevalence rate of RLS in a sample of patients with FMF and compare this prevalence with that of a matched normal population.

Method:

A total of 60 patients with FMF and 60 healthy controls were studied. All participants underwent a neurological examination. Diagnostic criteria as proposed by the International Restless Legs Syndrome Study Group (IRLSSG) were used to define RLS. The IRLSSG rating scale for the severity of RLS was applied to determine the severity of symptoms.

Results:

The prevalence of RLS was not significantly different between patients and controls. Although the mean International Restless Legs Syndrome Rating Scale (IRLSRS) scores tended to be higher in patients compared with controls, this difference was not significant. When each item of the severity scale was compared between the two groups, significantly higher scores were found in some items of the IRLSRS in patients with FMF compared with controls.

Conclusion:

According to this result, RLS symptoms in patients with FMF were more frequent and lasted longer than those in controls.

The Clinical Importance of Periodic Leg Movements in Sleep

OPINION STATEMENT

Periodic leg movements during sleep (PLMS) are commonly found in patients with restless leg syndrome (RLS), but they may occur in other sleep disorders and several medical conditions. Their prevalence increases with age, but they can also be observed in children. During the last decades, very active research has been devoted to determine and understand the pathophysiology, associated events, and clinical significance of PLMS. This chapter tries to sum up the most relevant PLMS-related findings, focusing on the relationship between PLMS and the cardiovascular system, in order to understand the clinical implication of this complex motor phenomenon. PLMS have been associated with sympathetic overactivity, namely surges in nocturnal blood pressure and heart rate, without modification in global autonomic balance. Also, PLMS have been related to inflammatory cellular pathways, with elevated level of inflammatory markers, which are associated with cardiovascular risk. The PLMS-related modulation of the autonomic system and of inflammation may increase cardiovascular and cerebrovascular risk in subjects with frequent PLMS. Moreover, also, comorbidities associated with PLMS may play a synergic role in worsening the cardiovascular risk and the consequent mortality and morbidity. Furthermore, little is known about pathophysiological correlates in children with PLMS and their chronic implication on the cardiovascular and cerebrovascular systems. A few studies have suggested that treating PLMS with dopaminergic drugs may reduce their associated sympathetic overactivity and modify disease progression. Definitely, further research is needed to assess the clinical impact of PLMS, associated or not with RLS, and above all the long-term impact of treating PLMS on cardiovascular risk, morbidity, and mortality.

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.

Identification and Treatment of New Inflammatory Triggers for Complex Regional Pain Syndrome: Small Intestinal Bacterial Overgrowth and Obstructive Sleep Apnea

Complex regional pain syndrome (CRPS) is evoked by conditions that may be associated with local and/or systemic inflammation. We present a case of long-standing CRPS in a patient with Ehlers-Danlos syndrome in which prolonged remission was attained by directing therapy toward concomitant small intestinal bacterial overgrowth, obstructive sleep apnea, and potential increased microglia activity. We theorize that cytokine production produced by small intestinal bacterial overgrowth and obstructive sleep apnea may act as stimuli for ongoing CRPS symptoms. CRPS may also benefit from the properties of low-dose naltrexone that blocks microglia Toll-like receptors and induces production of endorphins that regulate and reduce inflammation.

Prevalence and factors associated with disturbed sleep in patients with ankylosing spondylitis and non-radiographic axial spondyloarthritis: a systematic review

This review explores the prevalence and factors associated with disturbed sleep for patients with ankylosing spondylitis and non-radiographic axial spondyloarthritis in order to clarify consistent findings in this otherwise disparate research field. The association of physical, demographic and psychological factors correlating with poor sleep was explored, and the effectiveness of interventions assessed. Ten electronic databases were searched: AMED, CINAHL, Embase, Medline, PsycINFO, PubMed, Scopus, Web of Science, OpenGrey and BASE. Following application of inclusion and exclusion criteria, 29 articles were critically assessed on the basis of methodology, experimental design, ethics and quality of sleep data, leading to the selection of 15 studies for final review. Poor sleep was reported in 35-90% of patients with axial spondyloarthritis and is more prevalent within this clinical population compared to healthy control subjects. Disturbed sleep is an important aspect of disease for patients and reflects the severity of disease activity, pain, fatigue and functional disability. However, the direction of this relationship is undetermined. Associations with age, gender, years spent in education, quality of life and depression have also been demonstrated. Anti-TNF medication is effective in reducing poor sleep, and exercise has also produced beneficial results. Future research into poor sleep should take account of its multifactorial nature. There is also a current lack of research investigating non-pharmacological interventions or combination therapies. A standardised, validated measurement of poor sleep, appropriate for regular patient screening, would be a useful first step for future research.

Restless legs syndrome is associated with poor sleep quality and quality of life in patients with ankylosing spondylitis: a questionnaire-based study

We aimed to investigate the frequency of restless legs syndrome (RLS) and the associations between RLS and quality of sleep and life in patients with ankylosing spondylitis (AS). One hundred and eight AS patients and 64 controls were included in this study. Demographics, clinical, and laboratory data were recorded. The presence of RLS was determined with face-to-face interview by an experienced neurologist based on the International RLS Study Group criteria. RLS severity was evaluated using International RLS Study Group rating scale. Sleep quality and insomnia severity were assessed by Pittsburgh sleep quality index (PSQI) and insomnia severity index (ISI), respectively. Disease-related quality of life was evaluated by AS quality of life questionnaire (ASQoL). The frequency of RLS was significantly higher in AS patients than in controls (36.4 vs. 14.0 %, p = 0.004). RLS severity score for AS patients was significantly higher than that for controls (p = 0.03). The AS patients had higher scores in the subjective sleep quality, sleep latency, sleep duration, habitual sleep efficiency, sleep disturbances, use of sleep medication domains of PSQI, and also total PSQI and ISI than controls (p < 0.05, for all). ASQoL scores were higher in AS patients with RLS compared to those without RLS (p < 0.001). RLS severity was observed to be independently associated with total PSQI, ISI and ASQoL (p < 0.05, for all). As RLS may adversely affect the sleep and quality of life in AS patients, clinicians should be aware of RLS for early diagnosis and management in AS patients.

Mast cell activation disease and the modern epidemic of chronic inflammatory disease

A large and growing portion of the human population, especially in developed countries, suffers 1 or more chronic, often quite burdensome ailments which either are overtly inflammatory in nature or are suspected to be of inflammatory origin, but for which investigations to date have failed to identify specific causes, let alone unifying mechanisms underlying the multiple such ailments that often afflict such patients. Relatively recently described as a non-neoplastic cousin of the rare hematologic disease mastocytosis, mast cell (MC) activation syndrome-suspected to be of greatly heterogeneous, complex acquired clonality in many cases-is a potential underlying/unifying explanation for a diverse assortment of inflammatory ailments. A brief review of MC biology and how aberrant primary MC activation might lead to such a vast range of illness is presented.

Restless legs syndrome associated with major diseases: A systematic review and new concept

Recent publications on both the genetics and environmental factors of restless legs syndrome (RLS) defined as a clinical disorder suggest that overlapping genetic risk factors may play a role in primary (idiopathic) and secondary (symptomatic) RLS. Following a systematic literature search of RLS associated with comorbidities, we identified an increased prevalence of RLS only in iron deficiency and kidney disease. In cardiovascular disease, arterial hypertension, diabetes, migraine, and Parkinson disease, the methodology of studies was poor, but an association might be possible. There is insufficient evidence for conditions such as anemia (without iron deficiency), chronic obstructive pulmonary disease, multiple sclerosis, headache, stroke, narcolepsy, and ataxias. Based on possible gene-microenvironmental interaction, the classifications primary and secondary RLS may suggest an inappropriate causal relation. We recognize that in some conditions, treatment of the underlying disease should be achieved as far as possible to reduce or eliminate RLS symptoms. RLS might be seen as a continuous spectrum with a major genetic contribution at one end and a major environmental or comorbid disease contribution at the other.

Association of incident restless legs syndrome with outcomes in a large cohort of US veterans

Restless legs syndrome is a common sleep disorder, but there is a paucity of large cohort studies examining the association of restless legs syndrome with clinical outcomes, including all-cause mortality, incident coronary heart disease, stroke and chronic kidney disease. From a nationally representative prospective cohort of over 3 million US veterans [93% male, median follow-up time of 8.1 years (interquartile range: 7.0-8.5 years)] with baseline estimated glomerular filtration rate ≥ 60 mL min(-1) 1.73 m(-2), a propensity-matched cohort of 7392 patients was created, and the association between incident restless legs syndrome and the following was examined: (1) all-cause mortality; (2) incident coronary heart disease; (3) incident strokes; and (4) incident chronic kidney disease defined as estimated glomerular filtration rate <60 mL min(-1) 1.73 m(-2). Associations were examined using Cox models. The mean ± SD age of the propensity-matched cohort at baseline was 59 ± 12 years; 89 and 8% of patients were white and black, respectively; 31% of the patients were diabetic; and the mean baseline estimated glomerular filtration rate was 83.9 ± 15.1 mL min(-1) 1.73 m(-2). Propensity matching resulted in a balanced cohort, with the disappearance in baseline differences in comorbidities. Compared with restless legs syndrome-negative patients, incident restless legs syndrome was associated with 88% higher mortality risk [hazard ratio and 95% confidence interval: 1.88 (1.70-2.08)], and almost four times higher risk of coronary heart disease and stroke [hazard ratio: 3.97 (3.26-4.84) and 3.89 (3.07-4.94), respectively]. The risk of incident chronic kidney disease was also significantly higher in incident restless legs syndrome patients [hazard ratio: 3.17 (2.74-3.66)] compared with restless legs syndrome-negative counterparts. In this large and contemporary cohort of US veterans, incident restless legs syndrome was associated with higher risk of mortality, incident coronary heart disease, stroke and chronic kidney disease.

Restless Legs Symptoms and Pregnancy and Neonatal Outcomes

PURPOSE

Restless legs syndrome (RLS) is a commonly occurring neurologic disorder that affects up to one third of women during pregnancy. RLS has been associated with increased sympathetic tone in the nonpregnant population. We examined whether a RLS surrogate is associated with a higher prevalence of pregnancy and neonatal outcomes.

METHODS

Data were analyzed from a cross-sectional survey of 1000 women interviewed soon after delivery by using an RLS surrogate question. Women were asked how frequently (0 = none, 1 = rarely [<1 time/week], 2 = sometimes [1-2 times/week], 3 = frequently [3-4 times/week], and 4 = always [5-7 times/week]) they had "experienced jumpy or jerky leg movements" in the last 3 months of pregnancy. Clinical charts were reviewed to obtain relevant demographic and clinical data, including the presence of gestational hypertensive disorders and neonatal outcomes at birth. Subjects who "always" experienced RLS were compared with subjects experiencing symptoms less frequently or not at all with respect to prevalence of gestational hypertensive disorder.

FINDINGS

The mean ([SD]) age, prepregnancy body mass index (BMI), and BMI at delivery were 29.0 (6.1) years, 26.1 (6.2) kg/m(2), and 32.0 (6.3) kg/m(2), respectively. The overall prevalence of the RLS surrogate (jumpy or jerky leg movements) was 35.5% with the following distribution on a Likert scale: score 1 = 6.4%; score 2 = 10.2%; score 3 = 8.1%; and score 4 = 10.8%. Chronic hypertension was present in 2.1%, pregnancy-induced hypertension in 9.5%, and preeclampsia in 4.5% of respondents. Subjects who reported "always" having sensations of jumpy or jerky legs were more likely to have gestational hypertensive disorders compared with those who reported less frequent occurrence of the symptoms. Adjusted odds ratios were 3.74 (95% CI, 1.31-10.72; P = 0.014) for chronic hypertension; 1.26 (95% CI, 0.65-2.46; P = 0.487) for pregnancy-induced hypertension; and 2.15 (95% CI, 0.97-4.75; P = 0.060) for preeclampsia. There was a significant association between leg movement score and neonatal birth weight (coefficient, -149.5 g [95% CI, -276.9 to -22.5]; P = 0.005) and gestational age at birth (-0.7 week [95% CI, -1.1 to -0.2]; P = 0.021) that persisted after adjusting for preeclampsia, diabetes, and smoking.

IMPLICATIONS

A higher frequency of jumpy or jerky leg symptoms, a proxy for RLS during pregnancy, was associated with a higher likelihood of gestational hypertensive disorders and neonatal outcomes such as gestational age at birth and birth weight. These findings may affect RLS treatment decisions during pregnancy.

Relationships Between Malnutrition, Inflammation, Sleep Quality, and Restless Legs Syndrome in Hemodialysis Patients

Restless legs syndrome (RLS) is a common neurologic sensorimotor disorder. It is also seen in hemodialysis patients in whom the mechanism is not thoroughly understood. The aim of this study was to evaluate the association between malnutrition-inflammation score (MIS), sleep quality, and RLS in chronic hemodialysis patients. This cross-sectional study included 232 adult stable chronic hemodialysis patients (mean age 60.9 ± 14.1 years, 56.5% male). RLS frequency, MIS, Pittsburgh Sleep Quality Index (PSQI), laboratory data of patients as well as severity of RLS were evaluated. Thirty-seven patients (15.9%) were diagnosed with RLS. Mean MIS of patients with or without RLS were similar. PSQI of patients with RLS was significantly higher than patients without RLS (P = 0.002). There was a significant positive correlation between RLS severity and PSQI (r = 0.445, P = 0.006). A significant positive correlation was also found between PSQI and MIS in patients with RLS (r = 0.419, P = 0.010). RLS severity was positively correlated with some inflammatory parameters such as white blood cell count and C-reactive protein (r = 0.427, P = 0.008 and r = 0.418 P = 0.010). PSQI was found as an independent significant predictor of RLS (odds ratio [OR] = 1.15 (1.06-1.25), P = 0.001) in multivariate logistic regression analysis. Our study revealed that there was no significant relationship between RLS and MIS in chronic hemodialysis patients. However, RLS severity is correlated with inflammatory parameters. Also, sleep quality in chronic hemodialysis patients with RLS is negatively associated with MIS.

Quality measures for the care of adult patients with restless legs syndrome

ABSTRACT

The American Academy of Sleep Medicine (AASM) commissioned several Workgroups to develop quality measures for the care of patients with common sleep disorders, including adults with restless legs syndrome (RLS). Using the AASM process for quality measure development, the RLS Work-group developed three target outcomes for RLS management, including improving the accuracy of diagnosis, reducing symptom severity, and minimizing treatment complications. Seven processes were developed to support these outcomes. To achieve the outcome of improving accuracy of diagnosis, the use of accepted diagnostic criteria and assessment of iron stores are recommended. To realize the outcome of decreasing symptom severity, routine assessment of severity and provision of evidence-based treatment are recommended. To support the outcome of minimizing treatment complications, counseling about potential side effects and assessing for augmentation and impulse control disorders, when indicated, are recommended. Further research is needed to validate optimal practice processes to achieve best outcomes in adult patients with RLS.

Sleep disorders: A review of the interface between restless legs syndrome and iron metabolism

Restless legs syndrome (RLS) is characterized by unpleasant sensations mainly in the legs. 43% of RLS-associated conditions have also been associated with systemic iron deficiency. The objective of this study was to review in the literature the relationship between iron metabolism and RLS. With an initial search using the keywords combination “Iron Metabolism OR Iron Deficiency AND Restless Legs Syndrome,” 145 articles were screened, and 20 articles were selected. Few studies were found for this review in the period of 2001–2014, however, the correlation between RLS and iron was evident.

Current trends in the management of uremic restless legs syndrome: a systematic review on aspects related to quality of life, cardiovascular mortality and survival

Restless legs syndrome (RLS) affects almost one out of three end-stage renal disease patients. This review assesses the current treatment options for uremic RLS and the potential benefits of those treatments on quality of life parameters, cardiovascular mortality and survival. A systematic review was conducted searching PubMed and Scopus by using the Cochrane and PRISMA guidelines. Fourteen studies met the inclusion criteria in which the international RLS study group criteria were used as the primary diagnostic tool. Both pharmacological and non-pharmacological approaches were found to reduce the severity of uremic RLS symptoms. Only four studies reported changes on aspects related to quality of life while those changes were also associated with health benefits that resulted in reduced cardiovascular risk. The severity of uremic RLS symptoms can be ameliorated by using dopamine agonists and gabapentin, intravenous iron, exercise or supplementation with vitamins C and E, although some of those treatment benefits may be transient. There is a lack of strong evidence regarding the effects of the pharmacological approaches on quality of life and cardiovascular survival and mortality. In contrast exercise has been proven beneficial in both reducing the RLS symptoms' severity score and improving the quality of life.