Low RLS prevalence and awareness in central Greece: an epidemiological survey

Assessment of Sleep Disturbances on Mental Health in Patients with Restless Legs Syndrome

Background and Objective

In our study, we aimed to evaluate the sleep disturbances of patients diagnosed with restless legs syndrome (RLS) regarding their mental health according to the severity of the disease.

Materials and Methods

The study included 166 patients diagnosed with RLS and 161 healthy controls in the same age interval as patients. Sleep disturbances of patients were defined with the "personal information form" (PIF) prepared by the researchers, while the mental health status of patients was defined with the "Brief Symptom Inventory" (BSI).

Results

All RLS patients had an increase in BSI subscale points, with a positive correlation to disease severity, and subscale points were significantly higher than the control group (p < 0.05). Those with the "frequent waking" problem had higher BSI subscale points compared to those without the problem (p<0.01 or 0.001). Those with "waking with respiratory distress," "daytime sleepiness," "very early waking," and "sleep disorder" problems had statistically significantly high BSI subscale points for all subscales, apart from hostility, compared to those without these problems (p<0.01 or 0.001).

Conclusion

It is considered that assessment of sleep disturbances causing disrupted quality of life and mood disorders is beneficial for the treatment of patients with RLS. Our study data appears to be related to the result that sleep disturbances and mental health disruptions might be associated with the disease severity among RLS patients.

Restless leg syndrome in multiple sclerosis: a case-control study

Objectives

This study assessed the prevalence of restless leg syndrome (RLS) among patients with multiple sclerosis (pwMS) and the association between RLS and MS disease duration, sleep disturbance, and daytime fatigue.

Methods

In this cross-sectional study, we interviewed 123 patients via phone calls using preset questionnaires containing the International Restless Legs Syndrome Study Group (IRLSSG) diagnostic criteria, Pittsburgh Sleep Quality Index (PSQI), and Fatigue Severity Scale (FSS) diagnostic criteria validated in both Arabic and English. The prevalence of RLS in MS was compared to a group of healthy controls.

Results

The prevalence of RLS in pwMS, defined by meeting all four requirements included in the IRLSSG diagnostic criteria, was 30.3% compared to 8.3% in the control group. About 27.3% had mild RLS, 36.4% presented with moderate, and the remaining had severe or very severe symptoms. Patients with MS who experience RLS had a 2.8 times higher risk of fatigue compared to pwMS without RLS. pwMS with RLS had worse sleep quality, with a mean difference of 0.64 in the global PSQI score. Sleep disturbance and latency had the most significant impact on sleep quality.

Conclusion

The prevalence of RLS among MS patients was significantly higher compared to the control group. We recommend educating neurologists and general physicians to increase their awareness of the increasing prevalence of RLS and its association with fatigue and sleep disturbance in patients with MS.

Worldwide estimation of restless legs syndrome: a systematic review and meta-analysis of prevalence in the general adult population

This systematic review, meta-analysis and meta-regression assessed the prevalence of restless legs syndrome (RLS) in the general adult population. Studies identified in Scopus, PubMed, Web of Science, and PsycInfo between January 2000 and February 2022 were included if they used a case-control or cross-sectional design and reported data regarding the prevalence of RLS. The protocol was pre-registered in the International Prospective Register of Systematic Reviews (PROSPERO; CRD42022300709). A total of 97 studies including 483,079 participants from 33 different countries met the eligibility criteria. The Newcastle Ottawa Scale was used to evaluate the methodological quality, and the fill-and-trim method was used to correct probable publication bias, while the jack-knife method was performed to assess small study effect. The corrected overall pooled prevalence of RLS was 3% (95% confidence interval [CI] 1.4%-3.8%). The pooled prevalence of RLS syndrome was affected by methodological quality (no data from non-respondents in the included studies), gender (higher among women), study design (lower prevalence in case-control versus cohort and cross-sectional studies). The figures for corrected pooled prevalence among men, women, alcohol consumers and smokers were 2.8% (95% CI 2%-3.7%); 4.7% (95% CI 3.2%-6.3%); 1.4% (95% CI 0%-4.2%); and 2.7% (95% CI 0%-5.3%), respectively. The prevalence among male and female participants was lower in community-based versus non-community-based studies. Moreover, the prevalence was higher in developed versus developing countries and among elders versus adults. In conclusion, RLS is a common disorder in the general adult population, with a higher prevalence in women; however, prevalence data are affected by study design and quality.

Prevalence and Determinants of Restless Legs Syndrome (Willis-Ekbom Disease) in an Older Greek Population

OBJECTIVES

The present study aimed to explore the descriptive and analytic epidemiology of restless legs syndrome (RLS) in the older Greek population, with a specific focus on lifestyle indicators.

METHODS

Baseline data from the randomly selected non-demented older participants of the population-based HELIAD cohort were analyzed. Multivariable binary logistic regression with RLS diagnosis as the dichotomous dependent outcome was performed. Demographic, socioeconomic, anthropometric, dietary, sleep-related and psychological parameters, physical activity, use of psychoactive substances and personal medical history were investigated for potential associations.

RESULTS

A total of 133 from the eligible sample of 1,838 participants were diagnosed with RLS. The mean age-sex standardized prevalence of RLS among the elderly was estimated at 6.1% (95%CI = 5.0-7.2), with a female (8.0%, 95%CI = 6.4-9.6) to male (3.7%, 95%CI = 2.4-5.1) ratio of 2.1. The prevalence of RLS peaked during the 8^th decade of life and diminished thereafter. The positive associations of RLS with female sex [OR = 2.06, 95%CI = (1.19-3.57)], anxiety levels [assessed by the 22-point HADS scale, OR = 1.08, 95%CI = (1.03-1.13)] and traumatic brain injury [OR = 2.22, 95%CI = (1.37-3.62)] were reproduced. Good sleep quality was related to 55% [95%CI~(24-83%)] lower odds of having RLS in comparison with both poor and moderate quality. Adherence to the Mediterranean dietary pattern [assessed by a 55-point scale, OR = 1.06, 95%CI = (1.01-1.11)], and low daily energy intake [low-moderate vs. low: OR = 0.45, 95%CI = (0.26-0.79)]; [moderate-high vs. low: OR = 0.69, 95%CI = (0.40-1.22)]; [high vs. low: OR = 0.31, 95%CI = (0.13-0.69)] were related to RLS for the first time.

CONCLUSIONS

More emphasis should be placed on the dietary-nutritional aspects of RLS.

Restless Legs Syndrome Prevalence and Clinical Correlates Among Psychiatric Inpatients: A Multicenter Study

Background

There are only limited reports on the prevalence of restless legs syndrome (RLS) in patients with psychiatric disorders. The present study aimed to evaluate the prevalence and clinical correlates in psychiatric inpatients in Germany and Switzerland.

Methods

This is a multicenter cross-sectional study of psychiatric inpatients with an age above 18 years that were diagnosed and evaluated face-to-face using the International RLS Study Group criteria (IRLSSG) and the International RLS severity scale (IRLS). In addition to sociodemographic and biometric data, sleep quality and mood were assessed using the Pittsburgh Sleep Quality Index (PSQI), the Insomnia Severity Index (ISI), the Epworth Sleepiness Scale (ESS), and the Patient Health Questionnaire (PHQ-9). In addition to univariate statistics used to describe and statistically analyze differences in variables of interest between patients with and without RLS, a logistic model was employed to identify predictors for the occurrence of RLS.

Results

The prevalence of RLS in a sample of 317 psychiatric inpatients was 16.4%, and 76.9% of these were diagnosed with RLS for the first time. RLS severity was moderate to severe (IRLS ± SD: 20.3 ± 8.4). The prevalences in women (p = 0.0036) and in first-degree relatives with RLS (p = 0.0108) as well as the body mass index (BMI, p = 0.0161) were significantly higher among patients with RLS, while alcohol consumption was significantly lower in the RLS group. With the exception of atypical antipsychotics, treatment with psychotropic drugs was not associated with RLS symptoms. Regarding subjective sleep quality and mood, scores of the PSQI (p = 0.0007), ISI (p = 0.0003), and ESS (p = 0.0005) were higher in patients with RLS, while PHQ-9 scores were not different. A logistic regression analysis identified gender (OR 2.67; 95% CI [1.25; 5.72]), first-degree relatives with RLS (OR 3.29; 95% CI [1.11; 9.73], ESS score (OR 1.09; 95% CI [1.01; 1.17]), and rare alcohol consumption (OR 0.45; 95% CI [0.22; 0.94] as predictors for RLS.

Conclusions

Clinically significant RLS had a high prevalence in psychiatric patients. RLS was associated with higher BMI, impaired sleep quality, and lower alcohol consumption. A systematic assessment of restless legs symptoms might contribute to improve the treatment of psychiatric patients.

Association of quality of life, anxiety, and depression with restless leg syndrome in the hemodialysis patients

OBJECTIVES

Restless Legs Syndrome (RLS) is commonly known to cause morbidity in patients on hemodialysis, making them prone to chronic mental health illnesses such as depression and anxiety, and also adversely impact quality of life. In this study, we examined the association of quality of life, anxiety, and depression with restless leg syndrome in the hemodialysis patients at Karachi Institute of Kidney Diseases.

RESULTS

About 26.7% of the participants reported RLS among the sample size Presence of RLS was not associated with quality of life, depression, and anxiety. However, p-values < 0.05 were significant for body-mass index (BMI), diabetes mellitus as a cause of end-stage renal disease, and serum albumin levels. Majority (82.5%) of the RLS-diagnosed patients had moderate to severe symptoms with 16 (40%) and 17 (42.5%) clients, respectively.

Inflammatory bowel disease and restless leg syndrome

Objectives:

Inflammatory bowel disease (IBD) has been associated with restless leg syndrome (RLS). This study aims to explore the prevalence, clinical predictors, and severity of RLS in IBD patients compared to controls.

Methods:

We conducted a case-control study between January and December of 2019 comparing IBD patients with controls. Assessment of RLS was performed using the previously validated diagnostic restless leg syndrome questionnaire (RLSQ). Logistic regression analyses were applied to investigate associations between patient demographics and clinical features and RLS diagnosis.

Results:

A total of 218 IBD patients and 211 healthy controls were incorporated after excluding 6 patients with positional discomfort and 4 patients with habitual foot tapping. The mean age was 30.2±11.7 and 64% were females. The prevalence of RLS was 16/218 (7.34%) and 17/211 (8.06%) among cases and controls, respectively. Based on the RLSQ severity score, 6/16 (37.5%), 4/16 (25%) and 1/16 (6.3%) of the IBD patients with RLS had mild, moderate and severe RLS; respectively. The odds of IBD were lower among patients with confirmed RLS (OR=0.90, 95% CI=0.44-1.84, p = 0.78). In the logistic regression analysis, only vitamin B12 deficiency (OR=10.20, 95% CI=1.40-74.10, p = 0.022) was associated with RLS diagnosis among IBD patients.

Conclusion:

No difference was found in the prevalence of RLS between IBD patients and non-IBD controls. Vitamin B12 deficiency was associated with RLS diagnosis among patients with IBD.

The prevalence of common sleep disorders in young adults: a descriptive population-based study

Sleep disorders in adults are associated with adverse health effects including reduced quality of life and increased mortality. However, there is little information on sleep disorders in young adults. A cross-sectional observational study was undertaken in 1,227 young adults participating in the Western Australian Pregnancy (Raine) Study (2012–2014) to describe the prevalence of common sleep disorders. In-laboratory polysomnography (PSG) and validated survey methods were used, including the Epworth Sleepiness Scale, Pittsburgh Sleep Symptom Questionnaire-Insomnia, and International Restless Legs Syndrome Study Group criteria. A total of 1,146 participants completed a core questionnaire, 1,051 completed a sleep-focused questionnaire and 935 had analyzable PSG data. Participants had a mean age of 22.2 years and female to male ratio of 1.1 to 1. The respective sleep disorder prevalences in females and males were: obstructive sleep apnea (OSA) (apnea-hypopnea index [AHI]: ≥5 events/hour) 14.9% (95% CI: 11.8–18.5) and 26.9% (95% CI: 22.9–31.2); chronic insomnia, 19.3% (95% CI: 16.7–23.9) and 10.6% (95% CI: 8.3–13.9); restless legs syndrome, 3.8% (95% CI: 2.4–5.6) and 1.9% (95% CI: 0.9–3.4); and abnormal periodic leg movements during sleep (&gt;5 movements/hour), 8.6% (95% CI: 6.3–11.5) and 9.6% (95% CI: 7.1–12.7). There were statistically significant differences in prevalence between sexes for OSA and insomnia, which persisted after adjustment for body mass index and education. In those with complete data on all sleep-related assessments (n = 836), at least one sleep disorder was present in 41.0% of females and 42.3% of males. Sleep disorders are very common in young adults. Health practitioners should be aware of these high prevalences, as early identification and treatment can improve quality of life and may reduce later morbidity and mortality.

Reporting Quality of Randomized Controlled Trials in Restless Legs Syndrome Based on the CONSORT Statement

Background

Randomized controlled trials (RCTs) are the cornerstone of modern medical research, and their reporting may not always be optimal. The Consolidated Standards of Reporting Trials (CONSORT) statement is an evidence-based means to improve the quality of RCTs’ reporting by providing a checklist of recommended items.

The aim of this study was to assess the reporting quality of published RCTs on the restless legs syndrome (RLS), based on a checklist arising from the CONSORT statement.

Methods

Medical electronic databases were searched for RCTs involving patients with RLS. Inclusion criteria were follows: articles must have been published in English and RLS patients must have been randomized into a minimum of two treatment cohorts of different medicinal orientations. CONSORT-recommended items were marked as “reported” or “not reported,” and an overall CONSORT compliance metric was calculated. Comparisons among different time periods, CONSORT-endorsing and non-endorsing, and different levels of impact factor journals were made.

Results

Fifty-four eligible trials, published in 21 different scientific journals, were found. The average CONSORT compliance score was 56.6% (23.68–84.21%). CONSORT-endorsing journals had a mean CONSORT compliance of 58.47%, whereas non-endorsing journals had a mean CONSORT compliance of 50.4%. The median CONSORT compliance for articles published in low- (IF<2), medium- (IF 2-7), and high-ranked (IF>7) journals was 52.63, 56.57, and 59.21%, respectively. Only 14 of the 38 CONSORT items (36.8%) were reported in >75% of the articles.

Discussion

This study shows that the reporting of RLS-related RCTs is suboptimal, regardless of the time period, the quality of the publishing journal, and the endorsing or non-endorsing of the CONSORT statement.

Association Between the rs1229984 Polymorphism in the Alcohol Dehydrogenase 1B Gene and Risk for Restless Legs Syndrome

Background/Objectives

Several studies have raised the possibility of an association between alcohol consumption and the risk of developing restless legs syndrome (RLS). Moreover, an important percentage of patients under alcohol detoxification therapy develop RLS symptoms that fulfil the criteria for idiopathic RLS during alcohol withdrawal. We have aimed to establish the possible association between two common single nucleotide polymorphisms (SNPs) in the alcohol-dehydrogenase 1B (ADH1B) gene and the risk for RLS.

Methods

We studied, using specific TaqMan assays, the genotype and allelic variant frequencies of ADH1B rs1229984 and ADH1B rs6413413 SNPs in 205 RLS patients and 505 gender-matched healthy controls.

Results

The sum of the frequencies of rs1229984CT and rs1229984TT genotypes, as well as the frequency of the rs1229984T allelic variant, was significantly higher in RLS patients than in controls, both in the whole group and in females. The frequencies of genotypes and allelic variants of the rs6413413 SNP were similar between the two groups. RLS patients with the rs1229984CT genotype were younger, and those with the rs122984TT genotype older, at onset of RLS symptoms than those with the rs1229984CC genotype. None of the studied SNPs were related either with positivity of family history for RLS or with RLS severity.

Conclusions

These results suggest an association between rs1229984 SNP and the risk for RLS.

Restless Legs Syndrome/Willis-Ekbom Disease Is Prevalent in Working Nurses, but Seems Not to Be Associated with Shift Work Schedules

Insomnia and excessive sleepiness are among the most commonly reported sleep problems related to shift work. Sleep-related movement disorders have, however, received far less attention in relation to such work schedules. The objective of this study was to investigate the association between different shift work schedules and the prevalence of Restless legs syndrome/Willis–Ekbom disease (RLS/WED) in a large sample of Norwegian nurses. Our hypothesis was that shift working nurses would report higher prevalence of RLS/WED compared to day workers. A total of 1,788 nurses with different work schedules (day work, two-shift rotation, night work, three shift rotation) participated in a cohort study, started in 2008/2009. Four questions about RLS/WED based on the diagnostic criteria were included in wave 4 (2012). RLS/WED prevalence rates across different shift schedules were explored by the Pearson chi-square test. Logistic regression analysis was used to assess the association between RLS/WED and work schedules and shift work disorder (SWD) with adjustment for sex, age, marital status, smoking, and caffeine use. In total, 90.0% of the nurses were females, mean age 36.5 years (SD = 8.6, range 25–67). The overall prevalence of RLS/WED was 26.8%. We found no significant differences between the prevalence of RLS/WED across the different shift schedules, ranging from 23.3% (day work) to 29.4% (night work). There was a significant difference (p < 0.001) in the prevalence of RLS/WED between nurses having SWD (33.5%) compared to nurses not having SWD (23.8%). SWD remained significantly associated with RLS/WED in the adjusted logistic regression analysis (1.56, CI: 1.24–1.97). This study did not support the hypothesis. RLS/WED was associated with SWD, which might indicate that nurses vulnerable to shift work also are sensitive to other complaints related to a misalignment of the biological clock.

Restless legs syndrome/Willis-Ekbom disease prevalence in beta thalassemia patients

PURPOSE

Both beta thalassemia and restless legs syndrome (RLS) patients share some common pathophysiological characteristics related to iron handling. In the present study, the aim was to explore the prevalence of RLS as well as to explore potential association between the syndrome and various quality of life-related parameters in a sample of beta thalassemia patients.

METHODS

One hundred fourteen (age 40 ± 11 yr, 59 M/55F) beta thalassemia patients participated in this cross-sectional descriptive study. Patients were screened for RLS based on the international RLS study group diagnostic criteria as well as a battery of validated questionnaires.

RESULTS

The prevalence of RLS in this sample of beta thalassemia patients was zero. The quality of life score was low (78 ± 18). Iron levels were within normal range (191 ± 66 mcg/dL) while ferritin levels were high as expected (1836 ± 225 ng/dL).

CONCLUSIONS

Our sample of patients comes from central Greece where the prevalence of RLS in the general population is 4% while in renal failure patients is 27%. To our surprise, there was no presence of RLS among this sample of beta thalassemia patients. The adequate levels of iron and ferritin often seen in these patients could be the reason of the absence of RLS symptoms.

Increased Risk of Restless Legs Syndrome in Patients With Migraine: A Nationwide Population-Based Cohort Study

Previous studies suggest that an association between restless legs syndrome (RLS) and migraine exists. However, population-based data are unavailable in Asian cohorts. Our study thus aims to evaluate the association between migraine and RLS in a nationwide, population-based cohort in Taiwan and to examine the effects of age, sex, migraine subtype, and comorbidities on RLS development.Data from the Taiwan National Health Insurance Research Database were used. Patients aged 20 years or older with newly diagnosed migraine from 2000 to 2008 were included; 23,641 patients with newly diagnosed migraine and 94,564 subjects without migraine were randomly selected and followed until RLS development, withdrawal from the National Health Insurance, or until the end of 2011. A multivariate Cox proportional hazards regression model was used to explore the risk of RLS in patients with migraine after adjustment for demographic characteristics and comorbidities.Both cohorts were followed for a mean of 7.38 years. After adjustment for covariates, the risk of RLS was 1.42-fold higher (95% confidence interval = 1.13-1.79) in the migraine cohort than in the nonmigraine cohort (7.19 versus 3.42 years per 10,000 person-years). The increased risk was more prominent in males in the migraine cohort (1.87-fold increased risk, 95% confidence interval 1.22-2.85). Neither comorbidity status nor migraine subtype influenced the RLS risk.This population-based study demonstrated that migraine is associated with an increased risk of RLS compared with those without migraine, particularly in male patients with migraine and regardless of the comorbidity status.

Restless-legs syndrome and insomnia in hemodialysis patients

AIM/BACKGROUND

Restless legs syndrome (RLS) is a common neurological movement disorder which is commonly seen in hemodialysis (HD) patients. Insomnia, depression, and anxiety disorders frequently show concurrence. In this study, we aimed to investigate RLS and insomnia prevalence and related factors in HD patients.

SUBJECTS AND METHODS

Patients who were under HD treatment and healthy controls with similar mean age, sex ratio, and hypertension and diabetes mellitus frequency were included in this study. Depression, insomnia, and daytime sleepiness assessments were performed by using Beck Depression Inventory, Insomnia Severity Index, and Epworth Sleepiness Scale. The diagnosis of RLS was made using the International RLS Study Group consensus criteria.

RESULTS

About 156 HD patients and 35 controls were enrolled. The mean age was 50.6 in the HD group and 49.7 in the control group. Female sex was 43.9% in the HD group and 57.1% in the control group. RLS was significantly more frequent in HD patients compared with controls. The rate of sub-threshold insomnia and insomnia with moderate severity was higher in HD patients. While insomnia severity score and diabetes mellitus were significantly associated with the presence of RLS, depression, RLS, older age, and being under HD treatment were independently associated with insomnia severity.

CONCLUSIONS

HD patients commonly have RLS and insomnia. Insomnia and diabetes mellitus seem to be major factors underlying RLS in HD patients. Furthermore, depression and RLS seem to be closely related to insomnia in these patients. Treatment of depression, insomnia, and RLS may be beneficial to improve quality of life in HD patients.

Risk of Restless Legs Syndrome Following Tension-Type Headache: A Nationwide Population-Based Cohort Study

Migraine and restless legs syndrome (RLS) appear to be associated, but the relationship between tension-type headache (TTH) and RLS is unknown. This nationwide, population-based, retrospective cohort study explored the potential association between TTH and RLS.We identified 15,504 patients with newly diagnosed TTH from 2000 to 2007 and 62,016 individuals without TTH who were selected by frequency matched based on sex, age, and the index year. The study participants were followed until diagnosed with RLS, withdrawal from the NHI program, or the end of 2011. Cox proportional hazard models were used to identify risk factors for RLS in TTH patients.After adjusting for sex, age, comorbidity, and medications, TTH was significantly associated with an increased risk of RLS (hazard ratio [HR] = 1.57, 95% confidence interval [CI] = 1.22-2.02). The risk was most prominent in patients aged 20 to 39 years in the TTH group, which exhibited a 2.60-fold higher risk (95% confidence interval = 1.53-4.42) of RLS compared with the non-TTH group. The TTH group had a higher risk of RLS than that of the non-TTH group regardless of sex.Tension-type headache appears to be associated with an increased risk of developing RLS. This similarity to migraines may indicate that headache and RLS have a coincident pathophysiological mechanism, a possibility requiring further study. Clinicians should be more attentive to RLS as a possible comorbidity in patients with TTH.

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.

Restless legs syndrome and hypertension in Chinese pregnant women

Hypertension is a common complication of pregnancy, and studies show that pregnant women are more likely to suffer from restless legs syndrome (RLS). Pregnant women with hypertension and RLS often experience disrupted sleep patterns because of activation of the nervous system. The present study aimed to clarify the relationship between hypertension and RLS in pregnant women, and their impact on sleep. We enrolled 3,781 pregnant women who were admitted at our hospital for delivery between May 2011 and May 2014. The face-to-face questionnaire used to gather data included the International RLS Study Group criteria for diagnosis, Pittsburgh Sleep Quality Index (PSQI), Epworth Sleepiness Scale (ESS), and hypertension diagnosis. Depending on the time of occurrence of hypertension, it was divided into two different types: pregnancy-induced hypertension and chronic hypertension in pregnancy. Out of 3,781 patients, 453 fulfilled the diagnostic criteria for RLS and 486 met the diagnostic criteria for hypertension. Among patients with RLS, prophylactic iron supplementation was less frequently taken during pregnancy. Pregnancy-induced hypertension, rather than chronic hypertension in pregnancy, was found to be more frequent in patients with RLS; pregnant women with RLS had higher PSQI and ESS scores than pregnant controls. In our study, RLS was frequent in pregnant women, especially in those without prophylactic iron supplementation. Patients with RLS described more serious sleep disruption and excessive daytime sleepiness (EDS). In addition, pregnancy-induced hypertension was more common in patients with RLS.

The Hellenic Longitudinal Investigation of Aging and Diet (HELIAD): rationale, study design, and cohort description

BACKGROUND

Accumulating epidemiological evidence from several populations supports the important role of the Mediterranean-type diet (MeDi) in reducing the risk for age-related diseases such as Alzheimer's disease (AD). However, the relevant literature is clearly deficient for most Mediterranean countries that more closely adhere to the originally described MeDi. Greece resides in the Mediterranean basin, and older generations traditionally adhere to a MeDi.

METHODS

We here present the design and the preliminary baseline characteristics of the Hellenic Longitudinal Investigation of Aging and Diet (HELIAD). The HELIAD is a population-based, multidisciplinary, collaborative study designed to estimate the prevalence and incidence of AD, other dementias, mild cognitive impairment, and other neuropsychiatric conditions of aging in the Greek population and to investigate associations between nutrition and cognitive dysfunction/age-related neuropsychiatric diseases in this Mediterranean population. The study also ascertains several demographic, medical, social, environmental, clinical, nutritional, and neuropsychological determinants and lifestyle activities.

RESULTS

In total, 1,050 participants of a random sample have already completed the initial evaluation. The subjects were, on average, 73.4 (SD = 6.0) years old, 60% of the sample were female, and most of the participants were poorly educated with an average of 5.41 (SD = 3.5) years of education. The performance on the neuropsychological tests was equivalent to the average scores of previous normative Greek samples. More than one third of the population under investigation was considered to be at high risk for malnutrition.

CONCLUSIONS

The HELIAD may provide important data for expanding our knowledge regarding the prevalence, incidence, and risk factors of AD and several other neuropsychiatric diseases in the Mediterranean region.

Restless legs syndrome and pregnancy: a review

Restless legs syndrome (RLS) is a common sensorimotor neurological disorder that is diagnosed according to the revised criteria of the International RLS Study Group (IRLSSG). The pathophysiology of RLS is still unknown and its prevalence is influenced by ethnicity, age, and gender. RLS is divided into two types by etiology: primary or idiopathic and secondary. Primary RLS is strongly influenced by a genetic component while secondary RLS is caused by other associated conditions such as end-stage renal disease or peripheral neuropathy. Another common condition associated with RLS is pregnancy. The prevalence of RLS during pregnancy is two to three times higher than in the normal population and is influenced by the trimester and the number of parity. The main mechanisms that may contribute to the pathophysiology of RLS during pregnancy are hormonal changes and iron and folate status. Standard medications for treating RLS during pregnancy are not established. Most medications have been used according to the evidence from non-pregnant patients. Therefore, consideration of the medical treatment for treating RLS during pregnancy should be balanced between the benefit of relieving the symptoms and maternal and fetal risk. In general, the prognosis of RLS during pregnancy is good and symptoms are usually relieved after delivery.

Restless legs syndrome in an appalachian primary care population: prevalence, demographic and lifestyle correlates, and burden

BACKGROUND

Restless legs syndrome (RLS) is a common and distressing sensorimotor disorder of unknown etiology. While the epidemiology of RLS has been examined in several North American and European studies, research on RLS and RLS burden in poor, rural populations, including those residing in Appalachia, remains sparse. In this study, we investigated RLS prevalence in an Appalachian primary care population and examined the association of RLS to demographic factors, lifestyle characteristics, sleep quality, and mood disorders.

METHODS

Participants of this anonymous survey study were community-dwelling adults aged ≥ 18 years visiting one of 4 West Virginia primary care clinics. Data gathered included detailed information on sleep patterns, demographic characteristics, lifestyle factors, and health/medical history; the survey also included questions specific to RLS diagnosis and severity. Response rates were excellent, with 68% of eligible adults contacted returning completed surveys (N = 1,424/2,087). Pregnant women (N = 65) and those with missing data on key variables (N = 142) were excluded from the analyses.

RESULTS

Of the 1,217 participants included in the final analytic sample, 19.6% (18.2% with symptoms at least once/month) met the 4 IRLSSG diagnostic criteria in the absence of positional discomfort or leg cramps; 14.5% reported RLS symptoms at least once/week and 10.1% indicated symptoms ≥ 3×/week. Excluding respondents with diabetes, kidney disease, or anemia reduced these rates only slightly. Those with RLS were more likely to be older, female, lower income, unemployed, disabled, non-Hispanic white, and less likely to be college educated than those without RLS. Mood and sleep impairment were significantly elevated in those with RLS; after adjustment for demographic and lifestyle characteristics, health history, and other factors, those with RLS remained significantly more likely to indicate a history of depression (adjusted odds ratio [OR] = 1.9; 95% confidence interval [CI] = 1.4, 2.6) and anxiety (OR = 1.6, CI 1.1, 2.2), to report sleep impairment both 4 (OR = 2.4, CI 1.6, 3.7) and 7 days/week (OR = 1.8, CI 1.3, 2.4), and a mean sleep duration < 5 h/night (OR = 1.7, CI 1.2, 2.3). These associations increased in both strength and magnitude with increasing symptom frequency (p's for trend ≤ 0.01).

CONCLUSIONS

Findings of this preliminary anonymous survey study suggest that RLS prevalence is high in this Appalachian primary care population and that RLS is associated with significant burden in terms of both mood and sleep impairment.

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.

Prevalence of restless legs syndrome in a Georgian primary healthcare setting: a pilot study

BACKGROUND

The prevalence of restless legs syndrome (RLS) is approximately 10% in Western Europe, but unknown in Georgia. This pilot study aimed to assess RLS prevalence in a focused Georgian population.

METHODS

An RLS epidemiological questionnaire [Allen et al.: Sleep Med 2003;4:101-119] was filled out by patients in five primary healthcare centers in two Georgian cities between March and September 2006. Additionally, questions related to RLS symptom onset, family history, treatment, sleep disturbance and history of iron deficiency were included. RLS diagnosis was based on an expert interview and an epidemiological questionnaire for RLS.

RESULTS

The total number of respondents was 115 (75% women/25% men); mean age was 47 years (range 18-85). Thirteen subjects (11.3%) reported RLS symptoms (9 women/4 men); mean age was 52 years (range 32-83). Eleven (85%) had a positive family history of RLS. All subjects had sleep disturbance and none had a history of known iron deficiency.

CONCLUSION

The prevalence of RLS in a focused Georgian population is in line with other RLS epidemiologic studies performed in clinical settings. However, the prevalence rate of RLS in a studied group might not be representative for the general Georgian population. Further population-based epidemiological studies are required.

Socio-economic risk factors for incident restless legs syndrome in the general population

Few and controversial data exist about the relationship between socio-economic status and restless legs syndrome, and prospective analyses are lacking. We aimed to explore the associations between socio-economic factors and incident restless legs syndrome in the general population. Two prospective population-based cohort studies were conducted: the Dortmund Health Study with a mean follow-up of 2.2 years; and the Study of Health in Pomerania with a mean follow-up of 5.2 years. The studies included 1312 subjects and 4308 subjects, respectively. Restless legs syndrome was assessed twice according to the standard minimal criteria. The modified Winkler Index of social class, education, job status, partnership and income were assessed by interviews at baseline. The risk of restless legs syndrome associated with each socio-economic factor was estimated by multivariable logistic regression adjusted for behavioural factors and co-morbidities. Female gender, being retired and unemployment were independent risk factors of incident restless legs syndrome in both studies. Low level of education and income were independently associated with incident restless legs syndrome only in the Dortmund Health Study, but not in the other study. Migrational background and shiftwork were further independent risk factors of restless legs syndrome that were only assessed in the Dortmund Health Study. People with less favourable socio-economic situation are at an increased risk of developing restless legs syndrome. Behavioural variables and co-morbidities did not explain this association, thus further studies are required to reveal the mechanism behind the proposed relationship.

Prevalence and clinical characteristics of restless legs syndrome in chronic kidney disease patients

OBJECTIVE

To clarify the prevalence of restless legs syndrome (RLS) in the chronic kidney disease (CKD) population and determine the relationship between severity of renal dysfunction and risk of RLS as well as the impact of the disorder on mood and sleep disturbance, we conducted a questionnaire survey followed by face-to-face interviews with Japanese CKD patients.

METHODS

We sent a questionnaire battery including demographics items, the National Institutes of Health/International RLS Study Group (IRLSSG) consensus questionnaire, the Center for Epidemiological Studies Depression Scale, and the Pittsburgh Sleep Quality Index to eligible CKD patients (n=514) and age- and sex-matched controls (n=535). Structured interviews were performed for the diagnosis of RLS.

RESULTS

The prevalence of positive RLS in the CKD subjects was significantly higher than that in the controls (3.5% vs. 1.5%, p=0.029). The proportion of renal failure (RF) in CKD subjects with RLS was significantly higher than in those without RLS, and multiple logistic regression analysis revealed that the presence of RLS symptoms was associated only with the existence of RF. In addition, the presence of both RLS and CKD was significantly associated with the presence of depression and sleep disturbance.

CONCLUSIONS

The risk of RLS in the CKD population was higher than that in the general population and increased with the progression of renal dysfunction. Additionally, the existence of RLS might play a role in an increased risk for developing depression and sleep disturbance in the CKD population.

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.

Epidemiology of restless legs syndrome: a synthesis of the literature

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

MEIS1 and BTBD9: genetic association with restless leg syndrome in end stage renal disease

Background

Restless legs syndrome (RLS) is a sleep related movement disorder that occurs both in an idiopathic form and in symptomatic varieties. RLS is a frequent and distressing comorbidity in end stage renal disease (ESRD). For idiopathic RLS (iRLS), genetic risk factors have been identified, but their role in RLS in ESRD has not been investigated yet. Therefore, a case–control association study of these variants in ESRD patients was performed.

Methods

The study genotyped 10 iRLS associated variants at four loci encompassing the genes MEIS1, BTBD9, MAP2K5/SKOR1, and PTPRD, in two independent case–control samples from Germany and Greece using multiplex PCR and MALDI-TOF (matrix assisted laser desorption/ionisation time-of-flight) mass spectrometry. Statistical analysis was performed as logistic regression with age and gender as covariates. For the combined analysis a Cochran–Mantel–Haenszel test was applied.

Results

The study included 200 RLS-positive and 443 RLS-negative ESRD patients in the German sample, and 141 and 393 patients, respectively, in the Greek sample. In the German sample, variants in MEIS1 and BTBD9 were associated with RLS in ESRD (P_nom≤0.004, ORs 1.52 and 1.55), whereas, in the Greek sample, there was a trend for association to MAP2K5/SKOR1 and BTBD9 (P_nom≤0.08, ORs 1.41 and 1.33). In the combined analysis including all samples, BTBD9 was associated after correction for multiple testing (P_corrected=0.0013, OR 1.47).

Conclusions

This is the first demonstration of a genetic influence on RLS in ESRD patients with BTBD9 being significantly associated. The extent of the genetic predisposition could vary between different subgroups of RLS in ESRD.

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.

Randomized trials of dopamine agonists in restless legs syndrome: a systematic review, quality assessment, and meta-analysis

BACKGROUND

The use of dopamine agonists (DAs) for the treatment of restless legs syndrome (RLS) has been assessed in numerous randomized clinical trials (RCTs).

OBJECTIVES

The aims of this study were to assess the reporting quality of published RCTs according to the Consolidated Standards of Reporting Trials (CONSORT) statement and to synthesize the study results in terms of efficacy and tolerability to inform the clinical management of RLS.

METHODS

PubMed and Cochrane Controlled Trials Register were searched for English-language RCTs that assessed the effects of DAs in RLS. Quality of reporting was measured using the proportion of 17 CONSORT checklist items included in each study. The 2 primary outcomes were pooled mean change from baseline in International RLS (IRLS) Study Group rating scale score (Deltamu) (95% CI) and relative risk (RR) (95% CI) of response based on the Clinical Global Impression-Improvement (CGI-I) scale score. The pooled proportions of adverse events (PAEs) (95% CI) were also estimated.

RESULTS

Eighteen RCTs (N = 2848 patients) were included. Two of the 17 CONSORT checklist items were reported in 7 studies (39%) and 9 of the 17 items were reported in all 18 studies (100%). The differences in the IRLS scores and RR for CGI-I were significantly greater with pramipexole, ropinirole, rotigotine, and cabergoline compared with placebo. Results for heterogeneity were nonsignificant. The difference in Deltamu (95% CI) was significant with pramipexole (-6.63 [-9.15 to -4.10]) versus ropinirole (-3.64 [-4.76 to 2.51]) (P = 0.04). The difference between pramipexole and rotigotine was nonsignificant. The pooled PAEs (95% CI) for pramipexole, ropinirole, and rotigotine were 4.8% (2.0% to 8.7%), 10.2% (2.6% to 22.1%), and 7.6% (1.3% to 18.5%), respectively. In the trial of sumanirole, the PAE value was 2% (0% to 5.4%).

CONCLUSION

Based on the findings from the meta-analysis, DAs were significantly more efficacious in the treatment of RLS compared with placebo.

Prevalence of idiopathic and secondary restless legs syndrome in Korean Women

OBJECTIVE

The aim of this study was to identify the prevalence of idiopathic and secondary restless legs syndrome (RLS) and to compare them among Korean women.

METHODS

A total of 1000 women aged 40-69 years from the general population were included in the study. The questionnaire used to gather data included modified International Restless Legs Syndrome Study Group (IRLSSG) criteria, and questions related to RLS.

RESULTS

Of the entire cohort, 65 subjects were diagnosed as having RLS according to IRLSSG criteria. The overall prevalence of RLS was thus 6.5%. Of those subjects with symptoms of RLS, 81.5% complained of insomnia. The age at the onset of RLS was 38.9 +/- 8.6 years. RLS symptoms were experienced every day by 18.5% of affected subjects. None of the RLS subjects revealed in this study had previously been diagnosed or treated for their RLS problems.

CONCLUSION

The prevalence of RLS reported herein is low compared with that reported for Western countries. Our study provides further evidence for low prevalence of RLS in Asian populations and supports the view that RLS is poorly recognized by both physicians and the general population, resulting in suboptimal management of the disorder.