Restless legs syndrome: relationship between prevalence and latitude

Prevalence of restless legs syndrome in maintenance hemodialysis patients: A systematic review and meta-analysis

BACKGROUND

Restless legs syndrome is associated with quality of life and risk of death in maintenance hemodialysis patients. Although relevant meta-analyses have been conducted, epidemiological studies of restless legs syndrome have increased in recent years.

OBJECTIVE

Our aim was to systematically assess the prevalence of restless legs syndrome in maintenance hemodialysis patients and to evaluate the effect of different geographic regions, genders, study designs, and years of publication on the prevalence of restless legs syndrome.

METHODS

PubMed, Web of Science, EMBASE, The Cochrane Library, China Knowledge Resource Integrated Database, Wanfang Database, Weipu, and Chinese Biomedical Database were searched before March 16, 2023 for the published literature. Two investigators independently performed literature screening, data extraction for eligible studies, and risk of bias assessment. A random-effects model using the stata 15.0 software was used to assess the pooled prevalence of restless legs syndrome.

RESULTS

Fifty-seven articles were included in this meta-analysis, and the pooled prevalence of restless legs syndrome in 12,573 maintenance hemodialysis patients was 24.0 % (95 % CI: 21.0%-26.0 %). Maintenance hemodialysis patients from the Americas region and females had severe symptoms of restless legs syndrome, and the prevalence of restless legs syndrome increased from year to year. The prevalence of restless legs syndrome was higher in maintenance hemodialysis patients in cross-sectional studies and cohort studies compared to case-control studies.

CONCLUSIONS

Maintenance hemodialysis patients have a significantly higher prevalence of restless legs syndrome. These findings may provide some reference value for hospital nursing staff to focus on the management and treatment of restless legs syndrome in maintenance hemodialysis patients.

Review of the role of the endogenous opioid and melanocortin systems in the restless legs syndrome

Restless legs syndrome (RLS) is responsive to opioid, dopaminergic and iron-based treatments. Receptor blocker studies in RLS patients suggest that the therapeutic efficacy of opioids is specific to the opioid receptor and mediated indirectly through the dopaminergic system. An RLS autopsy study reveals decreases in endogenous opioids, β-endorphin and perhaps Met-enkephalin in the thalamus of RLS patients. A total opioid receptor knock-out (mu, delta and kappa) and a mu-opioid receptor knock-out mouse model of RLS show circadian motor changes akin to RLS and, although both models show sensory changes, the mu-opioid receptor knock mouse shows circadian sensory changes closest to those seen in idiopathic RLS. Both models show changes in striatal dopamine, anaemia and low serum iron. However, only in the total receptor knock-out mouse do we see the decreases in serum ferritin that are normally found in RLS. There are also decreases in serum iron when wild-type mice are administered a mu-opioid receptor blocker. In addition, the mu-opioid receptor knock-out mouse also shows increases in striatal zinc paralleling similar changes in RLS. Adrenocorticotropic hormone and α-melanocyte stimulating hormone are derived from pro-opiomelanocortin as is β-endorphin. However, they cause RLS-like symptoms and periodic limb movements when injected intraventricularly into rats. These results collectively suggest that an endogenous opioid deficiency is pathogenetic to RLS and that an altered melanocortin system may be causal to RLS as well.

Restless leg syndrome prevalence in epilepsy patients and its impact on quality of sleep

This study aimed to determine the frequency of restless leg syndrome (RLS) and other sleep-related movement disorders and their effects on sleep quality in epilepsy patients. One hundred and twenty-seven epilepsy patients were compared with 115 age-and gender-matched healthy controls. RLS was determined from the clinical characteristics of the patients according to the International RLS Study Group's (IRLSSG) diagnostic criteria. Sleep bruxism was diagnosed based on the International Classification of Sleep Disorders, Third Edition (ICSD-3) criteria. Subjective sleep quality was evaluated with the Pittsburgh Sleep Quality Index (PSQI). Poor sleep quality was more common in the epilepsy group than in the control group (42.5% versus 26.1%; p = 0.007). The epilepsy group had significantly higher PSQI total scores than the control group (p = 0.003). The frequency of RLS was higher in epileptic patients than in the control group (13.4% versus 5.2%; p = 0.024). There were no significant differences between the patient group and the control group regarding limb movement and bruxism frequency during sleep. The PSQI scores were high in epilepsy patients with RLS compared to those without RLS (p = 0.009). The frequency of habitual snoring, bruxism, and repetitive leg movement in sleep was also high in epilepsy patients with RLS compared to those without RLS (p < 0.05). The prevalence of poor sleep quality and RLS in epilepsy patients is higher than in healthy controls. Our results also show the negative impact of RLS on sleep quality in epilepsy patients. Further confirmatory studies using objective sleep tests are needed to identify the mechanisms underlying the current findings.

Restless Leg Syndrome Is Underdiagnosed in Hereditary Hemorrhagic Telangiectasia-Results of an Online Survey

BACKGROUND

Recurrent bleeding in patients with hereditary hemorrhagic telangiectasia (HHT) can lead to chronic iron deficiency anemia (CIDA). Existing research points to CIDA as a contributing factor in restless leg syndrome (RLS). The association between HHT-related symptoms and the prevalence of RLS was analyzed.

METHODS

An online survey was conducted whereby the standardized RLS-Diagnostic Index questionnaire (RLS-DI) was supplemented with 82 additional questions relating to HHT.

RESULTS

A total of 474 persons responded to the survey and completed responses for questions pertaining to RLS (mean age: 56 years, 68% females). Per RLS-DI criteria, 48 patients (48/322, 15%; 95% confidence interval (CI): 11-19%) self-identified as having RLS. An analysis of physician-diagnosed RLS and the RLS-DI revealed a relative frequency of RLS in HHT patients of 22% (95% CI: 18-27%). In fact, 8% (25/322; 95% CI: 5-11%) of the HHT patients had RLS which had not been diagnosed before. This equals 35% of the total amount of patients diagnosed with RLS (25/72; 95% CI: 25-46%). HHT patients with a history of gastrointestinal bleeding (prevalence ratio (PR) = 2.70, 95% CI: 1.53-4.77), blood transfusions (PR = 1.90, 95% CI: 1.27-2.86), or iron intake (PR = 2.05, 95% CI: 0.99-4.26) had an increased prevalence of RLS.

CONCLUSIONS

Our data suggest that RLS is underdiagnosed in HHT. In addition, physicians should assess CIDA parameters for possible iron supplementation.

Sleep and sleep disorders in pregnancy

Pregnancy is associated with a number of physiologic changes in the body including hormonal, anatomical, and mechanical. These changes alter many physiologic functions including sleep. The literature suggests that a number of women develop changes in duration, pattern, and quality of sleep during pregnancy. In addition, these changes also pave the way for expression of sleep disorders (e.g., insomnia, obstructive sleep apnea, and restless legs syndrome). Change in sleep and appearance of sleep disorders not only influence pregnant women, but also have negative influences on the fetus and outcomes of pregnancy. However, optimal management of these disorders may reverse adverse consequences. In this chapter, risk factors, clinical presentation, and management of insomnia, obstructive sleep apnea, and restless legs syndrome during pregnancy are discussed in view of the available literature.

Systematic review and meta-analysis of observational studies to understand the prevalence of restless legs syndrome in multiple sclerosis: an update

OBJECTIVE

Multiple sclerosis (MS) is related to the demyelination of intracranial nerves at multiple sites, while restless legs syndrome (RLS) appears to be caused by dysfunction of the dopaminergic system. Since RLS prevalence is higher among MS patients than in the general population, we carried out an updated meta-analysis to understand whether the two diseases might be associated.

METHOD

Web of Science, PubMed, Embase, Chinese National Knowledge Infrastructure, Wanfang, and SinoMed databases were searched for observational and case-controlled studies of RLS prevalence in MS. Eligible studies were meta-analyzed using Stata 12.0.

RESULTS

Pooled RLS prevalence among MS patients of various ethnicities was 26%, and prevalence was lower in Asia (20%) than outside Asia (27%). Prevalence was higher among cross-sectional studies (30%) than among case-control studies (23%). RLS prevalence was higher among female than male MS patients (26% vs. 17%), and it was higher among MS patients than among healthy controls (OR 3.96, 95%CI 3.29-4.77, p < 0.001).

CONCLUSION

Our meta-analysis updates the most recent meta-analysis in 2013 and provides perhaps the first reliable pooled estimate of RLS prevalence in MS. The available evidence strongly suggests that RLS risk is higher among MS patients than healthy controls.

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.

Restless Leg Syndrome Across the Globe: Epidemiology of the Restless Legs Syndrome/Willis-Ekbom Disease

There are more than 50 epidemiologic studies measuring the prevalence of restless legs syndrome/Willis-Ekbom disease (RLS/WED) across 5 of the 6 inhabited continents (not Australia), most conducted in North America and Europe. Sufficient studies have been conducted in Asia, North America, and Europe to make inferences on RLS/WED prevalence by region. RLS/WED prevalence is thought to be highest in North America and Europe and lower in Asia. These differences across regions may be explained by cultural, environmental, and genetic factors. Future investigation is needed to determine to what extent these factors affect expression of RLS/WED according to world region.

Headaches and sleep disorders

Headaches and sleep disorders are associated in a complex manner. Both the disorders are common in the general population, but the relationship between the two is more than coincidental. Sleep disorders can exacerbate headache sand the converse is also true. Treatment of sleep disorders can have a positive impact on the treatment of headaches. Screening for sleep disorders should be considered in all patients with headaches. This can be accomplished with brief screening tools. Those who screen positively can be further evaluated or referred to asleep specialist.

Restless Legs Syndrome: Would You Like That with Movements or Without?

The restless legs syndrome (RLS) is a common sensorimotor condition that often results in discomfort and sleep disturbance. Diagnosis of RLS is entirely clinical and based upon a patient's description of subjective symptoms, and thus when considering RLS diagnosis non-specificity is a real problem. RLS is associated with periodic limb movements during sleep (PLMS) in up to 90% of RLS sufferers; however, their presence is neither sufficient nor necessary for the diagnosis of RLS. The disease RLS and the motor phenomenon of PLMS share similarities in various areas, which include pathophysiology, pharmacology, genetics, and epidemiology. The purpose of this opinion piece is to outline the many similarities between RLS and PLMS in order to make an argument for the inclusion of PLMS as a supplementary diagnostic criterion of RLS, termed electro-clinical RLS, which would consist of the current clinical RLS diagnosis plus PLMS. This additional criterion could be used in cases where diagnosis is unclear to increase specificity or in research projects where proper diagnosis is desired at the investigational level.

The consequences for human health of stratospheric ozone depletion in association with other environmental factors

Ozone depletion, climate and human health.

The effects of periodic limb movements in sleep (PLMS) on cardiovascular disease

Periodic limb movements in sleep (PLMS) are uncontrollable nocturnal movements that occur during sleep and increase with age. Research has implicated PLMS as a contributing factor to the development of cardiovascular disease (CVD). The purpose of this manuscript is to 1) explain the sleep disorder of PLMS and implications on CVD; 2) identify the impact of PLMS on CVD; 3) discuss treatment options for PLMS; 4) present future research needs for PLMS/RLS; 5) provide implications to health care providers to improve the care and health outcomes of persons with PLMS.

Clinical and polysomnographic features of a large Turkish pedigree with restless leg syndrome and periodic limb movements

PURPOSE

Restless leg syndrome (RLS) and periodic limb movements (PLMS) are common neurological diseases often associated with insomnia. A familial aggregation in RLS has been identified since it was first described; however, inheritance patterns of RLS/PLMS are poorly understood and their exact pathophysiology is not well-known. We have identified a Turkish pedigree with RLS/PLMS, which is a rare condition, in five generations of a family, including nine affected family members.

METHODS

A detailed clinical evaluation of the family was conducted with the help of polysomnographic recording, electrophysiological findings, and biochemical parameters.

RESULTS

The proband is a 38-year-old male member of the family who first started to show symptoms at the age of 29. All the patients from this family have been diagnosed with RLS, according to the criteria of the International RLS Study Group. Disease onset was early in all cases and even earlier in the younger generation. Three affected individuals also had PLMS on polysomnographic recordings.

CONCLUSION

To our knowledge, this is the first Turkish family in which nine individuals in five generations are affected. We suggest an important effect of anticipation and genetic impact of the diseases and describe specific clinical features. Further investigation of clinical, genetic, and biochemical similarities between PLMS and RLS may yield important clues, adding to our understanding of the pathophysiology of these common diseases.