Why Are Women Prone to Restless Legs Syndrome?

The global and regional prevalence of restless legs syndrome among adults: A systematic review and modelling analysis

Background

Restless legs syndrome (RLS) is a prevalent neuro-sensory disorder that impairs quality of life. In this systematic review and modelling study, we estimated the global and regional prevalence of RLS and its associated factors.

Methods

We searched PubMed, Embase, and Medline for population-based studies on RLS prevalence published up to 12 November 2023. The included studies reported prevalence using the International Restless Leg Syndrome Study Group's (IRLSSG) minimal diagnostic criteria without limitations on frequency, duration, or severity. We applied a multilevel multivariable mixed-effects meta-regression to generate the age-specific and sex-specific prevalence of RLS for high socio-demographic index (H-SDI) and low and middle socio-demographic index (LM-SDI) regions. We pooled odds ratios (ORs) for RLS associated factors using random-effects models. Finally, we derived the regional prevalence and cases of RLS based on an associated factor-based model.

Results

From 52 articles across 23 countries, the global RLS prevalence in 2019 was estimated to be 7.12% (95% confidence interval (CI) = 5.15-9.76) among adults 20-79 years of age, equating to 356.07 million (95% CI = 257.61-488.09) affected individuals. Prevalence was similar in H-SDI (7.29%; 95% CI = 5.04-10.41) and LM-SDI (7.10%; 95% CI = 5.16-9.70) regions, with the majority of cases in LM-SDI countries (323.06 million; 90.73%). Europe had the highest (7.60%; 95% CI = 5.44-10.52) and Africa the lowest regional prevalence (6.48%; 95% CI = 4.70-8.87). The Western Pacific Region, meanwhile, had the most cases (111.91 million; 95% CI = 80.93-153.42). Factors positively associated with RLS included advanced age (OR = 1.13; 95% CI = 1.04-1.24), smoking (OR = 1.46; 95% CI = 1.29-1.64), depression (OR = 1.71; 95% CI = 1.26-2.32), and diabetes (OR = 1.54; 95% CI = 1.19-1.97).

Conclusions

A considerable global burden of RLS exists. Effective strategies are needed to increase awareness and optimise resource allocation to address this often-overlooked condition. High-quality epidemiological investigations employing standardised and rigorous criteria for RLS are essential for addressing RLS burden more effectively.

Registration

PROSPERO: CRD42020161860.

Prevalence and predictors of restless legs syndrome among patients having stable chronic obstructive pulmonary disease

BACKGROUND

Patients having COPD share some factors, e.g., chronic hypoxemia, anemia of chronic disease and nicotine use, which are also the risk factors for RLS hence predispose them to experience RLS in higher then general population. There are limited studies with methodological constraints evaluating the prevalence and/or correlates of RLS among patients with COPD.

METHODS

Consecutive adult patients of either gender, having stable COPD as per GOLD guidelines 2021, were assessed for RLS using IRLSSG (2014) criteria (excluding RLS mimics) and the severity of RLS was determined in participants having RLS. Phenomenology of RLS, past medical history and laboratory parameters were gathered. Insomnia and depression were assessed using the insomnia severity index and PHQ-9, respectively.

RESULTS

Participants' (N = 210) mean age was 63.02 ± 8.19 years, and 83.8% of subjects were men. 12.9% of participants were found to have RLS. Among those having RLS, nearly half (51.9%) had moderate symptoms, and 18.5% experienced severe symptoms. RLS was more prevalent among younger, females, those having severe COPD, participants having exacerbation of COPD in the previous year, lower post-bronchodilator FEV1, higher dyspnea and COPD assessment test score. Multivariate analysis showed that younger age, female gender, lower post-bronchodilator FEV1, lower FEV1/FVC ratio and higher serum creatinine increased the odds of having RLS. Depressive symptoms were more frequent in participants having RLS.

CONCLUSIONS

The present study found that the prevalence of RLS among patients with stable COPD was higher than the general population. Female gender, younger age, higher airflow limitation and higher serum creatinine (though in the physiological range) increase the odds of having RLS. Stable patients with COPD having these characteristics must be screened for RLS.

Prevalence and clinical correlates of restless legs syndrome in psychiatric patients: A cross-sectional study from North India

Background

Restless legs syndrome (RLS) is a neuro-sensorimotor disorder which is scarcely researched and is commonly missed in routine psychiatry practice.

Aim

To evaluate the prevalence of RLS and its correlates in patients with anxiety, depression, and somatoform disorders.

Methods

A cross-sectional single-center study was undertaken in patients aged 18-65 years suffering from ICD-10 (International Statistical Classification of Diseases-10th edition) diagnosis of anxiety, depressive, and somatoform disorders. RLS was evaluated by using diagnostic criteria of International Restless Legs Syndrome Study Group (IRLSSG) and severity measured on IRLSSG scale. Depression and anxiety were rated on Hamilton Depression and Anxiety Rating Scales respectively, insomnia severity measured by Insomnia Severity Index (ISI), and quality of life measured by WHO Quality of Life-Brief version (WHO-QOL BREF) scale. Serum ferritin levels were measured for evaluating iron deficiency.

Results

The rate of RLS was 66.7%, 50%, and 48% in patients with depressive, anxiety, and somatoform disorders, respectively, with no significant inter-group difference. Nearly one-third of patients suffered from severe to very severe symptoms of RLS, and quality of life was poorest in those with depressive disorders. RLS was significantly higher in females (P = 0.019), who were married (P = 0.040), diagnosed with severe depression (P = 0.029), and abused benzodiazepines (P = 0.045). On binary logistic regression, female gender and presence of clinical insomnia predicted occurrence of RLS.

Conclusion

The prevalence of RLS is very high in patients with common psychiatric disorders which is often missed. Clinical enquiry and examination for reversible causes such as iron deficiency may assist in its diagnosis and improve clinical outcome.

Sleep Disorders and Aging in Women

Women of advancing age can suffer from an array of sleep disorders. We review the changes in sleep architecture, the impact of hormonal changes on sleep, and the various sleep disorders in women of advancing age. A focused history in this population should include the temporal relation to menopause and comorbid conditions. Treatment options should involve patient preference and review of current medications and comorbid conditions to optimize sleep in this population.

Migraine and the Gender Divide

Migraine is a global neurologic disease that is highly prevalent, especially in women. Studies have observed a predisposition for the development of migraine in women, although the mechanisms involved have yet to be fully elucidated. This review aimed to summarize the recent evidence regarding the epidemiology, pathophysiology, and treatment of migraine and highlight key sex differences. We also identify gaps in care for both women and men living with migraine and discuss the presence of migraine-related stigma and how this may impact the efficacy of clinical care.

The effect of progressive muscle relaxation exercise on the intensity of symptoms and quality of sleep and quality of life in pregnant women with restless leg syndrome

OBJECTIVE

This study, accordingly, was conducted with the purpose of investigating the effect of progressive muscle relaxation exercise on the intensity of restless leg syndrome (RLS) and RLS-related quality of life and sleep in pregnant women with RLS.

METHODS

This one-centered, parallel randomized controlled study was conducted with 52 pregnant women. 27-28th of pregnancy, progressive muscle relaxation exercises training was shown and they were asked to practice them 3 times a week for 8 weeks.

RESULTS

It was found that the RLS Intensity Scale and PSQI posttest mean scores of the women in experiment group are lower on a statically significant level than the mean scores of the women in control group (p = 0.000 and p = 0.001). It was detected that the RLS-Qol posttest mean scores of the women in the experiment group are higher than the mean scores in the control group on a statistically significant level (p = 0.000).

CONCLUSIONS

It was seen that progressive muscle relaxation exercises alleviate RLS intensity and symptoms and improve RLS-related quality of life and sleep in pregnant women.

PRACTICE IMPLICATION

Progressive muscle relaxation exercises are beneficial for pregnant women and can be easily integrated into practice.

The genetic etiology of periodic limb movement in sleep

STUDY OBJECTIVES

Periodic limb movement in sleep is a common sleep phenotype characterized by repetitive leg movements that occur during or before sleep. We conducted a genome-wide association study (GWAS) of periodic limb movements in sleep (PLMS) using a joint analysis (i.e., discovery, replication, and joint meta-analysis) of four cohorts (MrOS, the Wisconsin Sleep Cohort Study, HypnoLaus, and MESA), comprised of 6843 total subjects.

METHODS

The MrOS study and Wisconsin Sleep Cohort Study (N = 1745 cases) were used for discovery. Replication in the HypnoLaus and MESA cohorts (1002 cases) preceded joint meta-analysis. We also performed LD score regression, estimated heritability, and computed genetic correlations between potentially associated traits such as restless leg syndrome (RLS) and insomnia. The causality and direction of the relationships between PLMS and RLS was evaluated using Mendelian randomization.

RESULTS

We found 2 independent loci were significantly associated with PLMS: rs113851554 (p = 3.51 × 10-12, β = 0.486), an SNP located in a putative regulatory element of intron eight of MEIS1 (2p14); and rs9369062 (p = 3.06 × 10-22, β = 0.2093), a SNP located in the intron region of BTBD9 (6p12); both of which were also lead signals in RLS GWAS. PLMS is genetically correlated with insomnia, risk of stroke, and RLS, but not with iron deficiency. Pleiotropy adjusted Mendelian randomization analysis identified a causal effect of RLS on PLMS.

CONCLUSIONS

Because PLMS is more common than RLS, PLMS may have multiple causes and additional studies are needed to further validate these findings.

Sex and Gender in Lung Diseases and Sleep Disorders: A State-of-the-Art Review: Part 2

There is now ample evidence that differences in sex and gender contribute to the incidence, susceptibility, presentation, diagnosis, and clinical course of many lung diseases. Some conditions are more prevalent in women, such as pulmonary arterial hypertension and sarcoidosis. Some life stages-such as pregnancy-are unique to women and can affect the onset and course of lung disease. Clinical presentation may differ as well, such as the higher number of exacerbations experienced by women with cystic fibrosis (CF), more fatigue in women with sarcoidosis, and more difficulty in achieving smoking cessation. Outcomes such as mortality may be different as well, as indicated by the higher mortality in women with CF. In addition, response to therapy and medication safety may also differ by sex, and yet, pharmacogenomic factors are often not adequately addressed in clinical trials. Various aspects of lung/sleep biology and pathobiology are impacted by female sex and female reproductive transitions. Differential gene expression or organ development can be impacted by these biological differences. Understanding these differences is the first step in moving toward precision medicine for all patients. This article is the second part of a state-of-the-art review of specific effects of sex and gender focused on epidemiology, disease presentation, risk factors, and management of selected lung diseases. We review the more recent literature and focus on guidelines incorporating sex and gender differences in pulmonary hypertension, CF and non-CF bronchiectasis, sarcoidosis, restless legs syndrome and insomnia, and critical illness. We also provide a summary of the effects of pregnancy on lung diseases and discuss the impact of sex and gender on tobacco use and treatment of nicotine use disorder.

Exploring the link between eating disorders and persistent genital arousal disorder/genito-pelvic dysesthesia: first description and a systematic review of the literature

BACKGROUND

Persistent Genital Arousal Disorder/Genito-Pelvic Dysesthesia (PGAD/GPD) characterized by recurrent physiological genital without corresponding psychological arousal is a poorly understood and researched condition. Based on the first two case descriptions of eating disorders directly linked to PGAD/GPD the aim of this paper was to systematically review the literature on possible associations between eating disorders and PGAD/GPD.

METHOD

A systematic literature search on eating disorders and PGAD/GPD was conducted in PubMed, PsycINFO, and Scopus, complemented by Google Scholar. We included case reports, case series, cross-sectional studies and review articles published in peer-reviewed journals written in English or German-language.

RESULTS

The included original papers described a total of 2078 cases with PGAD/GPD symptomatology. Of these, 892 participants fulfilled all five PGAD/GPD core criteria. The aetiology of PGAD/GPD is unknown. Multifactorial genesis of PGAD/GPD is presumed including neurological, pharmacological, hormonal, vascular and psychological causes. A high degree of psychological comorbidity is reported. No study was found that drew a direct link between eating disorders and PGAD/GPD. Although PGAD/GPD symptoms also occur in adolescents, there are no findings in this regard. However, we found a gap in data collection: eating disorders as potential psychiatric comorbidities were systematically recorded in only a few studies.

CONCLUSION

The existing literature have not yet considered a possible link between eating disorders and PGAD/GPD so far. According to the authors' knowledge, this work is the first review to systematically explore the associations. We suspect underreporting of PGAD/GPD cases in eating disorders and particularly during adolescence. We argue that there are several common factors that appear to be important in the etiology, course, and treatment of both disorders (e.g. hormonal dysregulation or sensory sensitivity and avoidance), warranting future research on the possible comorbidity of these disorders.

Is Restless Legs Syndrome De Facto Thyroid Disease?

While a primary role in the pathogenesis of restless legs syndrome (RLS) has been attributed to dysfunction of the dopaminergic system and impaired iron metabolism (particularly in the central nervous system), it has been hypothesized that an imbalance between thyroid hormones and dopaminergic activity may be the starting point for all aspects of RLS. Although this hypothesis was proposed more than a decade ago, it has not yet been verified beyond doubt. The main aim of this study is to compare the prevalence of RLS in a population of patients with the most common thyroid gland diseases with a population of individuals with a healthy thyroid gland. The study included 237 participants divided into smaller groups according to the thyroid disease concerning them. Each participant had a laboratory diagnosis, an ultrasound scan and an assessment of the fulfilment of RLS criteria according to the International Restless Legs Syndrome Study Group (IRLSSG) criteria. The results obtained were subjected to statistical analysis. RLS is significantly more common in patients with known thyroid disease; Hashimoto’s disease, among others, manifests a 2.56× higher risk of a positive diagnosis for RLS than the general population. The association of RLS with thyroid disease is notable, although it is difficult to conclude unequivocally that there is a cause-and-effect relationship between the two. Further investigation into a potentially autoimmune cause of restless legs syndrome should be considered.

Possible etiologies of restless legs syndrome in pregnancy: a narrative review

Restless legs syndrome (RLS) is a sensorimotor disorder characterized by an urgent need to move the legs, due to the presence of a discomfort sensation in the lower limbs, especially at rest. Generally, it relieves with movement. There are several studies that argue the existence of an association between this syndrome and pregnancy. However, the pathophysiological mechanisms of this disorder in pregnancy are misunderstood. The objective of this narrative review is to identify and discuss some possible etiologies of RLS in pregnancy. A literature search was performed in the PubMed and ResearchGate databases by using the following search strategies: "restless legs syndrome", "restless legs syndrome in pregnancy", "pregnancy and vitamin D deficiency" and "pregnancy and zinc". The publications were initially sorted through their title. After the initial process, inclusion and exclusion criteria were applied. The included articles were sorted by authors, year, journal of publication, type of study, and organized by chronological order of publication. Among the main findings, hormonal changes, iron metabolism, vitamin D deficiency, genetic factors, zinc and magnesium fluctuations have been some of the hypotheses supporting the development or worsening of this disorder in pregnancy. Dopamine also appears to be correlated with hormonal changes, iron metabolism, ferritin, folic acid and vitamin D deficiency. In conclusion, there are several hypotheses trying to link restless legs syndrome with pregnancy. The most covered were hormonal fluctuations and iron metabolism. However, this thematic is still highly discussed, creating the need for additional and thorough research.

Collaboration between Psychiatrists and Other Allied Medical Specialists for the Treatment of Delusional Disorders

Background: There is increasing evidence that individuals with psychosis are at increased risk for cardiovascular disease, diabetes, metabolic syndrome, and several other medical comorbidities. In delusional disorder (DD), this is particularly so because of the relatively late onset age. Aims: The aim of this narrative review is to synthesize the literature on the necessity for medical collaboration between psychiatrists and other specialists. Methods: A non-systematic narrative review was carried out of papers addressing referrals and cooperation among specialists in the care of DD patients. Results: Psychiatrists, the primary care providers for DD patients, depend on neurology to assess cognitive defects and rule out organic sources of delusions. Neurologists rely on psychiatry to help with patient adherence to treatment and the management of psychotropic drug side effects. Psychiatrists require ophthalmology/otolaryngology to treat sensory deficits that often precede delusions; reciprocally, psychiatric consults can help in instances of functional sensory impairment. Close collaboration with dermatologists is essential for treating delusional parasitosis and dysmorphophobia to ensure timely referrals to psychiatry. Conclusions: This review offers many other examples from the literature of the extent of overlap among medical specialties in the evaluation and effective treatment of DD. Optimal patient care requires close collaboration among specialties.

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.

The prevalence and potential aetiological factors associated with restless legs syndrome in patients with chronic kidney disease: a cross-sectional study

BACKGROUND

There is limited understanding of aetiological factors of and treatment options for restless leg syndrome (RLS) in patients with chronic kidney disease (CKD). This study aimed to estimate the prevalence of RLS in CKD patients and identify factors that may contribute to RLS.

METHODS

A questionnaire-based cross-sectional study of patients with CKD stage 4 (CKD 4), pre-dialysis stage 5 (CKD-5ND) and haemodialysis-dependent stage 5 (CKD-5D) was conducted. Eligible patients were enrolled from the local dialysis units and renal clinics. The International RLS Study Group rating scale was used to establish the diagnosis of RLS and quantify its severity.

RESULTS

212 patients with CKD 4 (n = 92), CKD-5ND (n = 14) and CKD-5D (n = 106) were included. The overall prevalence of RLS was 32.1%. Women had a significantly higher odds of having RLS despite adjustment for age, diabetes, cardiovascular disease and whether patients were on dialysis (odds ratio 2.8 [95% confidence intervals 1.5-5.2]). In pre-dialysis groups, patients with RLS had significantly higher serum ferritin (323.9 [SD 338.1] vs 177.5 [SD 178.5] µg/L, p = 0.020) compared to non-RLS patients. In dialysis patients (CKD-5D), those with RLS had significantly higher total white cell (8.0 [SD 3.5] vs 6.8 [SD 1.9] × 10⁹/L, p = 0.026) and neutrophil (6.4 [SD 3.9] vs 4.6 [SD1.7] × 10⁹/L, p = 0.002) counts compared to patients without RLS.

CONCLUSION

RLS remains a significant problem in patients with CKD and may be related to underlying inflammation. Targeting this pathway may be useful. Prevalence of RLS, diagnosed using validated measures, is higher than previous reports.

TRIAL REGISTRATION

N/A (the current study is not a trial).

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.

Grey matter alterations in restless legs syndrome: A coordinate-based meta-analysis

Brain structural abnormalities in idiopathic restless legs syndrome have long been debated. Voxel-based morphometry is an objective structural magnetic resonance imaging technique to investigate regional grey matter volume or density differences between groups. In the last decade, voxel-based morphometry studies have exhibited inconsistent and conflicting findings regarding the presence and localization of brain grey matter alterations in restless legs syndrome. We therefore conducted a coordinate-based meta-analysis to quantitatively examine whether there were consistent grey matter findings in restless legs syndrome using the latest algorithms, seed-based d mapping with permutation of subject images. We included 12 voxel-based morphometry studies (13 datasets, 375 patients and 385 healthy controls). Our coordinate-based meta-analysis did not identify evidence of consistent grey matter alterations in restless legs syndrome. Grey matter alterations via voxel-based morphometry analysis are not therefore recommended to be used as a reliable surrogate neuroimaging marker for restless legs syndrome. This lack of consistency may be attributed to differences in sample size, genetics, gender distribution and age at onset, clinical heterogeneity (clinical course, anatomical distribution of symptoms, disease severity, disease duration, abnormal sensory profiles and comorbidity), and variations in imaging acquisition, data processing and statistical strategies. Longitudinal studies with multimodal neuroimaging techniques are needed to determine whether structural changes are dynamic and secondary to functional abnormalities.

Sensory symptoms in body-focused repetitive behaviors, restless legs syndrome, and Tourette syndrome: An overlap?

Tourette syndrome (TS) is a neurodevelopmental condition characterized by multiple tics. Sensory symptoms play a key role in the clinical phenomenology and pathophysiology of TS, as most patients report premonitory urges driving tic expression. Interestingly, sensory symptoms have also been reported in other conditions characterized by repeated behaviors. This review explores the nature of sensory symptoms reported by patients with body focused repetitive behaviors (BFRBs, especially trichotillomania and skin picking disorder) and restless legs syndrome (RLS) in comparison to TS. A sense of mounting inner tension and reinforcement mechanisms driven by gratification and relief on expression of the tic or repetitive behavior appear to be implicated across all conditions. Subjective urges can be temporarily suppressed by patients with TS and selected BFRBs, whereas patients with RLS tend to report dysesthesia more frequently than a suppressible urge to move. The observed similarities in the phenomenology of sensory symptoms across these conditions raise the possibility of a comparable underlying pathophysiology. Preliminary findings suggest an overlap of neural pathways encompassing the insula, basal ganglia (putamen), and posterior cingulate cortex.