Restless legs syndrome and pregnancy or delivery complications in China: a representative survey

Prevalence and factors associated with restless legs syndrome among pregnant women in middle-income countries: a systematic review and meta-analysis

Introduction

Restless legs syndrome (RLS) is a debilitating condition characterized by uncomfortable sensations in the legs, typically occurring during periods of rest or sleep. It is more prevalent during pregnancy and is linked to sleep disturbances, diminished quality of life, and pregnancy complications. However, previous studies yielded inconsistent findings among pregnant women in middle-income countries. Consequently, this systematic review and meta-analysis sought to determine the pooled prevalence of restless legs syndrome and its associated factors in these populations.

Method

A systematic review and meta-analysis was conducted on published studies from middle-income countries until May 2023. The review strictly adhered to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Relevant search terms were used to search for studies in PubMed, MEDLINE, EMBASE, and Google Scholar. Data extraction was performed using the Joanna Briggs Institute tool for prevalence studies. The meta-analysis was conducted using STATA 17 software, and heterogeneity was assessed using the I2 test, while publication bias was evaluated using Egger's test. Forest plots were also used to present the pooled prevalence and odds ratio (OR) with a 95% confidence interval (CI) using the random-effects model.

Result

This review included 22 studies from nine countries with a total of 17, 580 study participants. The overall pooled prevalence of RLS among pregnant women in middle-income countries was 13.82% (95% CI: 13.31, 14.32), and having low hemoglobin level (AOR: 1.68, 95% CI: 1.29, 2.18), history of RLS (AOR: 7.54, 95% CI: 3.02, 18.79), muscle cramps (AOR: 3.58, 95% CI: 1.21, 10.61), excessive day time sleepiness (AOR: 4.02, 95% CI: 1.34, 12.04), preeclampsia (AOR: 2.06, 95% CI: 1.28, 3.30), and taking prophylactic iron supplementation (AOR: 0.59, 95% CI: 0.50, 0.69) were the identified factors associated with it.

Conclusion

Generally, nearly one in every eight pregnant women in middle-income countries develop restless legs syndrome during pregnancy. Having low hemoglobin level, a history of RLS, muscle cramps, excessive daytime sleepiness, preeclampsia, and taking prophylactic iron supplementation were the identified factors associated with it. These findings underscore the importance of addressing the identified factors associated with RLS in order to effectively mitigate its occurrence among pregnant women.

Common sleep disorders in pregnancy: a review

In this review, we provide a comprehensive overview of common sleep disorders during pregnancy, including their characterization, prevalence, risk factors, and possible contribution to maternal and fetal outcomes. We conducted a quasi-systematic literature search of the MEDLINE database and identified 744 studies from 1991 through 2021, inclusive, that met our inclusion criteria. We synthesized the existing literature on sleep disorders during pregnancy and highlighted controversies, research gaps, and needed clinical developments. Our review covers a range of sleep disorders, including insomnia, obstructive sleep apnea, restless legs syndrome, and circadian rhythm disorders. We discuss the prevalence of these disorders in pregnancy and their potential impact on maternal and fetal health outcomes. We also explore the relationship between sleep disorders, pre-pregnancy comorbidities such as obesity, and pregnancy-related conditions such as gestational diabetes mellitus and preeclampsia. In addition to summarizing the existing literature on sleep disorders during pregnancy, we also highlight opportunities for further research in this area. We suggest that future studies should strive to employ validated and objective measurement tools for sleep disorders and prioritize utilization of longitudinal methods with participant follow-up through postpartum, mid-life, menopause, and beyond. We also put forward investigation into the impact of circadian rhythm disruption on reproductive physiology and early pregnancy outcomes as an area of important work. Overall, our review provides valuable insights on sleep and reproduction and into common sleep disorders during pregnancy and their potential impact on maternal and fetal health outcomes.

The Prevalence of Restless Legs Syndrome Among Pregnant Women in Saudi Arabia

INTRODUCTION

Pregnancy has been associated with restless legs syndrome (RLS). RLS is underdiagnosed in most countries. The purpose of this study was to assess the prevalence of RLS among Saudi pregnant women.

METHODS

This cross-sectional study included 459 pregnant women from all Saudi provinces between December 2022 and March 2023. A structured online questionnaire assessing demographic and pregnancy characteristics, medical conditions, sleep quality, and RLS symptoms was conducted.

RESULTS

The prevalence of RLS was 26.6% among the participants. Calcium deficiency was significantly associated with RLS (adjusted odds ratio (OR)=2.16, 95% confidence interval (CI)=1.2-3.9, p=0.01), but there was no significant association between RLS and vitamin D and iron deficiencies (p>0.05), according to multivariate binary logistic regression analysis. Moreover, RLS increased the risk of insomnia and frequent waking up (adjusted OR=4.95, 95% CI=2.50-9.83, p<0.001, and adjusted OR=2.87, 95% CI=1.55-5.32, p=0.001, respectively).

CONCLUSION

RLS is common among pregnant women in Saudi Arabia. The study indicates that RLS during pregnancy is linked to calcium deficiency and negatively affects sleep quality.

Prevalence of restless leg syndrome and effects on quality of life during pregnancy

PURPOSE

Restless leg syndrome (RLS) is a movement disorder which constitutes the most common and major risk group during pregnancy. The purpose of this study was to determine prevalence and severity of RLS during pregnancy and to investigate the effect of RLS on quality of life in pregnant women.

METHODS

This cross-sectional study was conducted in antenatal clinics of four different public hospitals. Data collected were pregnancy assessment form, RLS diagnostic criteria form, RLS severity scale, and SF-12 quality of life scale.

RESULTS

Among 718 pregnant women, mean age was 28.3±5.9 years (range 19 to 45). According to the diagnostic criteria of RLS, RLS prevalence was 22% (n=159). Of the 159 women with RLS, 41% had moderate severity and 40% had severe RLS. Prevalence of RLS in pregnant women increased with gestational week, working time during pregnancy, weight before pregnancy, total weight gain during pregnancy, and pre-pregnancy body mass index. Physical health scores, physical functioning scores, pain scores, emotional role difficulty scores, and social function scores were significantly lower in the pregnant women with RLS than without RLS (p <0.05).

CONCLUSIONS

Approximately one-fifth of the pregnant women had RLS, mostly in the third trimester, and the severity of RLS was predominantly moderate and severe. Pregnant women with RLS had poorer quality of life than pregnant women without RLS.

Sleep disturbances during pregnancy and adverse maternal and fetal outcomes: A systematic review and meta-analysis

Sleep disturbances are highly prevalent in pregnancy and are frequently overlooked as a potential cause of significant morbidity. The association between sleep disturbances and pregnancy outcomes remains largely controversial and needs to be clarified to guide management. To evaluate the association between sleep disturbances and maternal complications and adverse fetal outcomes, we performed a systematic search of PubMed, Embase and Web of Science for English-language articles published from inception to March 6, 2020, including observational studies of pregnant women with and without sleep disturbances assessing the risk of obstetric complications in the antenatal, intrapartum or postnatal period, and neonatal complications. Data extraction was completed independently by two reviewers. We utilized the Newcastle-Ottawa Scales to assess the methodological quality of included studies and random-effect models to pool the associations. A total of 120 studies with 58,123,250 pregnant women were included. Sleep disturbances were assessed, including poor sleep quality, extreme sleep duration, insomnia symptoms, restless legs syndrome, subjective sleep-disordered breathing and diagnosed obstructive sleep apnea. Significant associations were found between sleep disturbances in pregnancy and a variety of maternal complications and adverse fetal outcomes. Overall sleep disturbances were significantly associated with pre-eclampsia (odds ratio = 2.80, 95% confidence interval: 2.38-3.30), gestational hypertension (1.74, 1.54-1.97), gestational diabetes mellitus (1.59, 1.45-1.76), cesarean section (1.47, 1.31-1.64), preterm birth (1.38, 1.26-1.51), large for gestational age (1.40, 1.11-1.77), and stillbirth (1.25, 1.08-1.45), but not small for gestational age (1.03, 0.92-1.16), or low birth weight (1.27, 0.98-1.64). Sleep disturbances were related to higher morbidities in pregnant women who are 30 y or older and overweight before pregnancy. The findings indicate that sleep disturbances, which are easily ignored and treatable for both pregnant women and clinical services, deserve more attention from health care providers during prenatal counseling and health care services.

New onset of restless legs syndrome in pregnancy in a prospective multiracial cohort: Incidence and risk factors

OBJECTIVE

To determine whether the incidence and risk factors of restless legs syndrome (RLS) in pregnancy differ by race/ethnicity, we estimated relative risks of demographic, socioeconomic, and nutritional factors in association with risk of any incident RLS in pregnancy in a cohort of 2,704 healthy pregnant women without prior RLS.

METHODS

Using data from the multicenter, multiracial National Institute of Child Health and Human Development (NICHD) Fetal Growth Studies-Singletons, we examined the incidence of RLS from early pregnancy to near delivery through up to 6 assessments. Multivariable Poisson models with robust variance were applied to estimate relative risks (RRs).

RESULTS

The cumulative incidence of RLS in pregnancy was 18.1% for all women, 20.3% for White women, 15.4% for Black women, 17.1% for Hispanic women, and 21.1% for Asian women. Among Hispanic women, older age (RR [reference ≤25 years]: 25-35 years, 1.51; 95% confidence interval [CI] 1.05-2.16; ≥35 years, 1.58; 95% CI 0.93-2.68), anemia (RR [reference no]: yes, 2.47; 95% CI 1.31-4.64), and greater total skinfolds of the subscapular and triceps sites, independent of body mass index (RR [reference quartile 1]: quartile 5, 2.54; 95% CI 1.30-4.97; p trend = 0.01) were associated with higher risk of RLS, while multiparity was associated with a lower risk (RR [reference nulliparity]: 0.69; 95% CI 0.50-0.96). In Black women, greater skinfolds and waist circumference were associated with higher risk of pregnancy RLS, although the trends were less clear.

CONCLUSIONS

The incidence of RLS in pregnancy was high and differed by race/ethnicity, which is likely accounted for by differences in other risk factors, such as age, parity, and nutritional factors.

Unraveling the Mysteries of Restless Leg Syndrome

Restless leg syndrome (RLS) or Willis-Ekbom disease (WED) is an under-diagnosed, chronic, and progressive primary sensory-motor disorder. It is characterized by an uncontrollable urge to move the legs due to uncomfortable and sometimes painful sensations, with a diurnal variation. RLS can lead to severe sleep disturbances, a usual cause of consultation. The pathophysiology is known partially, and it is believed that there is an association between the different variants of genetic mutations combined with dopaminergic and brain iron dysregulation, which plays an important role. The data used for this study were extracted from the articles found in the PubMed database that discuss different gene variants, pathophysiology, and various methods of treatment. They also highlight the role of iron in the pathogenesis of RLS as it is required for the synthesis of tyrosine hydroxylase, which is the rate-limiting step for dopamine synthesis. This review article provides a clinically useful overview of RLS in terms of pathophysiological findings, its genetic associations, and therapeutic options by using the currently available literature. Because RLS presents with vague symptoms and shares similarities with many other diseases, it might be overlooked by many physicians resulting in underdiagnosis and under-treatment. While these discoveries provide a breakthrough in understanding the details of RLS, further studies are recommended as these studies are limited to animal models and provide a limited representation of the general population.

Associations Between Sleep Disorders and Hypertensive Disorders of Pregnancy and Materno-fetal Consequences

PURPOSE OF THE REVIEW

To review the data supporting the associations between sleep disorders and hypertensive disorders of pregnancy, their diagnosis, consequences, treatment, and potential mechanisms.

RECENT FINDINGS

The prevalence of sleep-disordered breathing, insomnia, and restless legs syndrome increases as pregnancy progresses secondary to physiologic changes associated with pregnancy. Sleep-disordered breathing is strongly associated with the development of gestational hypertension and preeclampsia, both of which are associated with increased risk of perinatal complications. Diagnosing sleep disorders in pregnant presents added challenges, but polysomnography remains the gold standard for diagnosing sleep-disordered breathing in this group. Sleep disorders, and especially sleep-disordered breathing, are highly prevalent among pregnant women and associated with hypertensive disorders of pregnancy. Clinicians should be mindful of this association and endeavor to identify at-risk women for further evaluation.

Maternal and neonatal outcomes associated with restless legs syndrome in pregnancy: A systematic review

Restless legs syndrome (RLS) affects one in five pregnant women. This review aims to synthesise evidence regarding gestational RLS and its consequences on pregnant women and neonates. Search of Embase, MEDLINE, PsycINFO, Maternity and Infant Care and Scopus was conducted in July 2018 using MeSH headings and keywords for 'restless legs syndrome' and 'pregnancy' or 'birth'. Our search identified 16 eligible studies from 12 countries published between 2004 and 2018 concerning gestational RLS and one or more maternal, delivery or neonatal outcomes. The most consistent associations were observed between gestational RLS and increased risks of gestational hypertension, pre-eclampsia, and peripartum depression. There were mixed findings for caesarean delivery, preterm birth and low birth weight, with the majority reporting no association with gestational RLS. Gestational RLS was not associated with postpartum haemorrhage, gestational diabetes, fetal distress, or low Apgar scores. Future research is needed to investigate whether effective treatment of RLS can mitigate these potential harms. Validated methods for diagnosing RLS in pregnancy would support research in this growing field.

Restless Legs Syndrome and Severe Preeclampsia: A Case-Control Study

OBJECTIVE

This study sought to determine whether there is an association between restless legs syndrome (RLS) and severe preeclampsia using a case-control study design.

METHODS

A total of 147 patients with severe preeclampsia and 147 patients with normal pregnancies were evaluated for symptoms of RLS. In the first phase, before or immediately after delivery, participants were given a questionnaire on common complaints experienced during pregnancy. Mixed with these complaints were the symptoms that comprised the diagnostic criteria for RLS. If a participant indicated she met the diagnositic criteria, she was informed about RLS. In the second phase, a severity evaluation was performed in this population using the International Restless Legs Syndrome Study Group Rating Scale.

RESULTS

Among the participants, independent of the presence of preeclampsia, 13.61% met the criteria for a diagnosis of RLS. There was no statistical difference between groups (severe preeclampsia: 12.93% vs. controls: 14.29%; odds ratio [OR] 0.89; 95% CI 0.46-1.74, P = 0.37). After analysis, 65% of patients with RLS had a score on the International Restless Legs Syndrome Study Group Rating Scale compatible with "very severe" or "severe" RLS. There was again no statistical difference between groups for the combination of "severe" and "very severe" scoring criteria (severe preeclampsia: 68.42% vs. controls: 61.90%; OR 1.33; 95% CI 0.36-4.93, P = 0.66) and "very severe" alone (severe preeclampsia: 21.05% vs. controls: 4.76%; OR 5.33; 95% CI 0.54-52.73, P = 0.11).

CONCLUSION

The prevalence of RLS among pregnant women in our study was in accordance with the medical literature and avoided the probable bias caused by the high number of other symptoms experienced during pregnancy. There were no significant differences between normotensive participants and those with severe preeclampsia. In general, symptom severity was high, with a tendency toward greater severity in patients with severe preeclampsia, but this difference did not reach statistical significance.

Characteristics of sleep/wake problems and delivery outcomes among pregnant Japanese women without gestational complications

Background

Frequently observed sleep/wake problems among pregnant women need comprehensive evaluation. This study was conducted to clarify the sleep/wake problems among pregnant women without gestational complications during the second and third trimester and the effects of sleep/wake problems on delivery outcomes.

Methods

A total of 88 Japanese pregnant women participated in this study. In their second and third trimester, subjective sleep quality, insomnia severity, excessive daytime sleepiness (EDS), and restless legs syndrome/Willis-Ekbom disease (RLS/WED) were assessed using questionnaires; also, sleep disordered breathing (SDB) was screened using a pulse oximeter.

Results

From the second to the third trimester, an increasing tendency of sleep/wake problems was observed. During the third trimester, the percentages of women experiencing decreased subjective sleep quality, difficulty maintaining sleep (DMS), EDS, RLS/WED, and 3% oxygen desaturation index (ODI) values ≥5/h were 62.5, 45.5, 48.9, 9.1, and 29.5%, respectively. In a logistic regression analysis for EDS in the third trimester, the adjusted odds ratio (95% confidence interval) of total sleep duration < 6 h, moderate to severe DMS, and 3% ODI values ≥5/h were 3.25 (1.16–9.10), 4.74 (1.60–14.00), and 0.90 (0.28–2.89), respectively. Although short sleep durations, decreased subjective sleep quality, EDS, and SDB did not affect delivery outcomes or the infant’s condition, the percentage of women undergoing cesarean sections in the severe insomnia group was significantly higher (p = 0.008).

Conclusions

Sleep/wake problems were frequent during pregnancy, especially during the third trimester. EDS among pregnant women was associated with shorter sleep durations and DMS rather than SDB. The effect of factors related to insomnia on delivery outcomes should thus be considered a crucial problem among pregnant Japanese women without gestational complications in clinical practice.

Restless Legs Syndrome in Pregnant Thai Women: Prevalence, Predictive Factors, and Natural Course

BACKGROUND AND PURPOSE

Restless legs syndrome (RLS) is a common sleep-related neurological disorder that affects the quality of sleep. This study aimed to estimate the prevalence, predictive factors, and natural course of RLS, and its effect on sleep quality in pregnant Thai women.

METHODS

A cross-sectional study that included 214 pregnant women was performed. RLS was diagnosed according to the revised criteria of the International RLS Study Group (IRLSSG). General demographic and antenatal-care data were reviewed. Scores on the Thai versions of the Epworth Sleepiness Scale (ESS), Pittsburgh Sleep Quality Index, and the IRLSSG Rating Scale were determined.

RESULTS

RLS was diagnosed in 24 of the pregnant women (11.2%): 4.2%, 25.0%, and 70.8% in the first, second, and third trimesters, respectively. Multiple logistic regression analysis revealed that a hemoglobin level (Hb) less than 11 g/dL [odds ratio (OR)=3.21, 95% CI=1.27-8.13] and a history of RLS (OR=16.62, 95% CI=1.52-181.32) were associated with RLS during pregnancy. Subjects with RLS significantly had higher Thai-ESS scores (p<0.01). All subjects with RLS had severe symptoms that subsided within 1 week after delivery. No immediate labor complication was associated with RLS.

CONCLUSIONS

Our study has confirmed a high prevalence of RLS and its impacts on sleep in pregnant women. An Hb of less than 11 g/dL and a history of RLS are predictive factors for RLS developing during pregnancy. Pregnancy-related RLS has a benign course and usually disappears within 1 week after delivery.

Evaluation of Cardiovascular Risk Factors and Restless Legs Syndrome in Women and Men: A Preliminary Population-Based Study in China

STUDY OBJECTIVES

Many studies have investigated the association between restless legs syndrome (RLS) and cardiovascular risk factors, leading to conflicting results. Therefore, the aim of the current study was to determine whether RLS is associated with cardiovascular risk factors and disease.

METHODS

This cross-sectional study included 5,324 consecutive subjects who visited the Physical Examination Center of The First Affiliated Hospital of Zhengzhou University for their yearly routine physical examination. Participants underwent a face-to-face interview with a neurologist for the assessment of RLS, based on the International Restless Legs Study Group criteria. They also completed a questionnaire related to cardiovascular risk factors and other health-related and demographic information. Logistic regression was used to assess which of the demographic and cardiovascular risk factors increased the odds of RLS. Then, unadjusted and adjusted models were designed to determine whether RLS was associated with increased odds of cardiovascular disease, coronary artery disease, or hypertension.

RESULTS

RLS was observed in 9.2% of the participants. Multivariable logistic regression models, which included the covariates age, sex, body mass index, smoking status, hypercholesterolemia, and Pittsburgh Sleep Quality Index score (dichotomized at 5), demonstrated that female sex (odds ratio [OR]: 2.42, 95% confidence interval [CI]: 1.99-2.95), smoking (OR: 1.96, 95% CI: 1.31-2.92), high cholesterol (OR: 1.30, 95% CI: 1.03-1.64), and PSQI score > 5 (OR: 5.61, 95% CI: 2.14-14.69) are significantly associated with RLS. Additionally, RLS was associated with hypertension, after adjusting for age, sex, body mass index, smoking, hypercholesterolemia, Pittsburgh Sleep Quality Index score > 5, diabetes, anemia, and decreased renal function.

CONCLUSIONS

RLS is associated with the prevalence of hypertension but not with that of cardiovascular disease or coronary artery disease.

Prevalence of restless legs syndrome during pregnancy: A systematic review and meta-analysis

Pregnant women are more likely to be affected by restless legs syndrome (RLS) than the general population. Restless legs syndrome during pregnancy is associated with adverse maternal and fetal outcomes. Currently unknown is the worldwide and regional prevalence of RLS in pregnant women. We performed a meta-analysis to provide a full profile of the prevalence of RLS during pregnancy. A systematic search of the PubMed, Medline, EMBASE, and Web of Science databases was performed to identify studies that were published up to April 2017, followed by random-effects meta-analyses. A total of 196 articles were identified, among which 27 longitudinal and cross-sectional observational studies with 51,717 pregnant subjects were included in the analysis. The pooled overall prevalence of RLS across all three trimesters was 21%. According to the regional classification of the World health organization, the prevalence of RLS during pregnancy in the European Region, Western Pacific Region, Eastern Mediterranean Region, and Region of the Americas was 22%, 14%, 30%, and 20%, respectively. The regional prevalence in the African Region and South-East Asia Region was not assessed because of insufficient data. We also analyzed the prevalence of RLS in the first, second, and third trimesters of pregnancy, and the rates of RLS were 8%, 16%, and 22%, respectively. We also found that the high prevalence of RLS decreased to 4% after delivery. No publication bias was found in these analyses. The findings emphasize the high occurrence of RLS during pregnancy. Future studies should examine the effects of RLS during pregnancy on maternal and fetal outcomes.

Restless Legs Syndrome and Sleep-Wake Disturbances in Pregnancy

STUDY OBJECTIVES

To estimate the association of restless legs syndrome (RLS) and its frequency with sleep-wake disturbances in pregnancy.

METHODS

A cohort of 1,563 women in their third trimester of pregnancy were recruited from prenatal clinics between March 2007 and December 2010. Demographic, pregnancy, and delivery data were extracted from medical records and sleep information was collected with questionnaires. To diagnose RLS, we used standardized criteria of RLS symptoms and frequency that were developed by the International Restless Legs Study Group. Logistic regression models were constructed to investigate the association of RLS and its frequency with sleep-wake disturbances (poor sleep quality, daytime sleepiness, poor daytime function) and delivery outcomes.

RESULTS

Overall 36% of the pregnant women had RLS, and half had moderate to severe symptoms. Compared to women without RLS, those with RLS were more likely to have poor sleep quality (odds ratio [OR] 2.2, 95% confidence interval [CI] 1.7-2.9), poor daytime function (OR 1.9, 95% CI 1.4-2.4), and excessive daytime sleepiness (OR 1.6, 95% CI 1.3-2.0). A dose-response relationship also was evident between RLS frequency and each of the sleep-wake disturbances. There was no evidence for any association between RLS and delivery outcomes.

CONCLUSIONS

RLS is a significant contributor to poor sleep quality, daytime sleepiness, and poor daytime function, all common and often debilitating conditions in pregnancy. Obstetric health care providers should be aware of these associations and screen women for RLS.

COMMENTARY

A commentary on this article appears in this issue on page 857.

Managing Sleep Disorders during Pregnancy

Sleep disturbances and disorders are common during pregnancy, and they can be risk factors for a number of serious pregnancy-related sleep disorders. These include postpartum depression, pregnancy-induced hypertension, gestational diabetes, and intrauterine growth retardation. In addition, certain chronic sleep disorders, such as narcolepsy, are quite challenging to manage in the context of pregnancy and during lactation, particularly with medications that can be teratogenic. This review discusses 4 common sleep disorders and their impacts on pregnancy, and suggests ways to deal with these disorders that improves maternal and fetal outcomes safely. The review discusses diagnosis and treatment of obstructive sleep apnea, restless legs syndrome, insomnia, and narcolepsy in pregnancy.