Efficacy and safety of TOMAC for treatment of medication-naïve and medication-refractory restless legs syndrome: A randomized clinical trial and meta-analysis.

OBJECTIVE/BACKGROUND: There is a significant unmet need for safe and effective nonpharmacological therapies for restless legs syndrome (RLS). The objective was to evaluate the efficacy and safety of tonic motor activation (TOMAC) in patients with RLS. PATIENTS/METHODS: A multicenter, randomized, participant-blinded, sham-controlled trial enrolled 45 adults with primary moderate-to-severe RLS who were either medication-naïve (n = 20) or medication-refractory (n = 25). Participants were 1:1 randomized to TOMAC (n = 22) or sham (n = 23) for two weeks and instructed to self-administer 30-min TOMAC sessions when they experienced RLS symptoms. The primary outcome was mean change in International RLS Study Group Rating Scale (IRLS) total score. A subsequent meta-analysis included the present trial and a previous randomized clinical trial that enrolled medication-naïve RLS patients. RESULTS: IRLS reduction was significantly greater for TOMAC than sham (TOMAC -6.59 vs. sham -2.17; mean difference (MD) = -4.42; 95 % confidence interval [CI] -1.57 to -7.26; p = 0.0040). Subgroup analysis showed similar IRLS mean difference for medication-refractory (MD = -4.50; p = 0.02) and medication-naïve (MD = -4.40; p = 0.08) cohorts, which was significantly different from sham only for the medication-refractory cohort. Meta-analysis of combined data from 33 medication-naïve RLS patients showed a significant reduction in mean IRLS score after two weeks for TOMAC compared to sham (MD = -4.30; 95 % CI -1.36 to -7.24; p = 0.004). CONCLUSIONS: The present trial confirmed previous reports documenting efficacy and safety of TOMAC in refractory RLS and indicated similar effect sizes in refractory versus naïve subgroups. The meta-analysis demonstrated that TOMAC significantly improves RLS symptoms in naïve participants.

Rethinking clinical trials in restless legs syndrome: A roadmap.

The number of large clinical trials of restless legs syndrome (RLS) have decreased in recent years, this coincides with reduced interest in developing and testing novel pharmaceuticals. Therefore, the International Restless Legs Syndrome Study Group (IRLSSG) formed a task force of global experts to examine the causes of these trends and make recommendations to facilitate new clinical trials. In our article, we delve into potential complications linked to the diagnostic definition of RLS, identify subpopulations necessitating more attention, and highlight issues pertaining to endpoints and study frameworks. In particular, we recommend developing alternative scoring methods for more accurate RLS diagnosis, thereby improving clinical trial specificity. Furthermore, enhancing the precision of endpoints will increase study effect sizes and mitigate study costs. Suggestions to achieve this include developing online, real-time sleep diaries with high-frequency sampling of nightly sleep latency and the use of PLMs as surrogate markers. Furthermore, to reduce the placebo response, strategies should be adopted that include placebo run-in periods. As RLS is frequently a chronic condition, priority should be given to long-term studies, using a randomized, placebo-controlled, withdrawal design. Lastly, new populations should be investigated to develop targeted treatments such as mild RLS, pregnancy, hemodialysis, or iron-deficient anemia.

Prevalence of restless legs syndrome during pregnancy and postpartum period.

OBJECTIVES: Restless legs syndrome (RLS) is a disease from the spectrum of movement disorders, the prevalence of which increases significantly during pregnancy and is associated with poor sleep, a drop in daytime energy, and the development of psychological disorders during pregnancy and the postpartum period. METHODS: The IRLSS scale was used to determine the presence of RLS symptoms. The total test sample that included the tested and control groups was (n=390) subjects. The examined group consisted of pregnant women (n=260), and the control group consisted of female students (n=130). In total, 260 pregnant women were monitored 6 months after pregnancy. Three measurements were performed, first in the third trimester of pregnancy, second two months after delivery, third 6 months after delivery, while one cross-sectional measurement was performed for the control group. RESULTS: The prevalence of RLS in pregnancy is highest in the third trimester and amounts to 26.5 %. In the postpartum period, a significant decrease in the prevalence of RLS was observed, measured two months after delivery (18.1 %). Postpartum, over time, a decrease in the prevalence of RLS was noticed, and six months after delivery it was (7.3 %), when it practically approached the prevalence of the control group (standard population) which was (6.2 %). CONCLUSIONS: The prevalence of RLS is highest during the third trimester of pregnancy and decreases after delivery so that 6 months after delivery it approaches the prevalence of the standard population.

Alterations in functional brain connectivity following treatment for restless legs syndrome: The role of symptom improvement in restoring functional connectivity.

The pathophysiology of restless legs syndrome (RLS) remains incompletely understood. Although several studies have investigated the alterations of brain connectivity as one of the pathophysiological mechanisms of RLS, there are only few reports on functional connectivity changes after RLS treatment. Forty-nine patients with newly diagnosed RLS and 50 healthy controls were prospectively enrolled. The patients underwent resting-state functional magnetic resonance imaging (rs-fMRI) at baseline, and 39 patients underwent follow-up rs-fMRI, 3 months after treatment with pramipexole or pregabalin. Patients were divided into good or poor medication response groups. Functional brain connectivity was analysed using rs-fMRI and graph theoretical analysis. Significant differences in functional connectivity were observed between the RLS patients and healthy controls. The average path length, clustering coefficient, transitivity, and local efficiency were lower (2.02 vs. 2.30, p < 0.001; 0.45 vs. 0.56, p < 0.001; 3.08 vs. 4.21, p < 0.001; and 0.71 vs. 0.76, p < 0.001, respectively) and the global efficiency was higher (0.53 vs. 0.50, p < 0.001) in patients with RLS than in healthy controls. Differences in functional connectivity at the global level were also observed between post- and pre-treatment RLS patients who showed a good medication response. Transitivity in the post-treatment group was higher than that in the pre-treatment group (3.22 vs. 3.04, p = 0.007). Global efficiency was positively correlated with RLS severity (r = 0.377, p = 0.007). This study demonstrates that RLS is associated with distinct alterations in brain connectivity, which can be partially normalised following symptom management. These findings suggest that therapeutic interventions for RLS modulate brain function, emphasising the importance of symptom-focussed treatment in managing RLS.

Iron Deficiency and Sleep/Wake Behaviors: A Scoping Review of Clinical Practice Guidelines-How to Overcome the Current Conundrum?

Current evidence suggests that iron deficiency (ID) plays a key role in the pathogenesis of conditions presenting with restlessness such as attention deficit hyperactivity disorder (ADHD) and restless legs syndrome (RLS). In clinical practice, ID and iron supplementation are not routinely considered in the diagnostic work-up and/or as a treatment option in such conditions. Therefore, we conducted a scoping literature review of ID guidelines. Of the 58 guidelines included, only 9 included RLS, and 3 included ADHD. Ferritin was the most frequently cited biomarker, though cutoff values varied between guidelines and depending on additional factors such as age, sex, and comorbidities. Recommendations surrounding measurable iron biomarkers and cutoff values varied between guidelines; moreover, despite capturing the role of inflammation as a concept, most guidelines often did not include recommendations for how to assess this. This lack of harmonization on the interpretation of iron and inflammation biomarkers raises questions about the applicability of current guidelines in clinical practice. Further, the majority of ID guidelines in this review did not include the ID-associated disorders, ADHD and RLS. As ID can be associated with altered movement patterns, a novel consensus is needed for investigating and interpreting iron status in the context of different clinical phenotypes.

Serum ferritin measurements differ according to assay used: implications for iron therapy in restless legs syndrome.

STUDY OBJECTIVES: Serum ferritin levels are used to determine the need for iron supplementation in patients with RLS. The purpose of the study was to determine whether immunoassay measurement of serum ferritin yields varying levels according to different manufacturer assays, with resultant variation in cut off values. METHODS: We compared serum ferritin levels using 116 clinical samples assessed by the Beckman and Roche methods. RESULTS: While there was a high correlation between results obtained from the 2 methods (R2 = 0,99), the absolute values differed. The equivalent ferritin measures determined by Beckman, Roche were: 50 mcg/dL, 83 mcg/dL; 75 mcg/dL, 121 mcg/dL; 100 mcg/dL, 158 mcg/dL; and 300 mcg/dL, 457 mcg/dL. CONCLUSIONS: It is uncertain which assays were used to measure serum ferritin in the seminal studies on which current guidelines for iron therapy for RLS are based. In view of this uncertainty, as well as the limited data on which current recommendations are based, clinicians should be flexible in using recommended serum ferritin cut off values, also utilizing percentage transferrin saturation. Assuming that Beckman or equivalent assays were used, centers using the Roche method need to adjust the cut offs for administration of oral iron and intravenous iron recommended by current practice guidelines to avoid withholding treatment for RLS patients who might benefit from iron supplementation.

Sex-based disparities in dopamine agonist response in patients with restless legs syndrome.

This study aimed to investigate sex-related differences in the response to ropinirole and pramipexole in patients with restless legs syndrome (RLS). By analysing clinical parameters and polysomnographic (PSG) findings, we sought to elucidate the potential factors related to sex disparities modulating treatment responses and sleep quality in RLS. A total of 41 drug-free patients with RLS, aged ≥18 years, underwent two consecutive nocturnal PSG recordings, without medication at baseline; before the second night, 26 patients received an oral dose of 0.25 mg pramipexole whereas 15 received 0.5 mg ropinirole. After each PSG recording, patients self-evaluated the severity of their previous night symptoms by means of an ad hoc visual analogue scale (VAS). At baseline, sleep efficiency and percentage of Stage N2 tended to be higher in females while wakefulness after sleep onset was significantly higher in males. After treatment, total leg movements during sleep (LMS), periodic LMS (PLMS), and periodicity indexes were significantly lower in females than in males. The VAS score was lower after treatment in all patients, without differences between the two sexes. This study demonstrates a higher acute responsiveness of PLMS to dopamine agonists (pramipexole and ropinirole) in females than in males with RLS. These findings might be explained by differential sex-related expression of dopamine receptors, especially D3, within the central nervous system. In addition, our findings provide translational hints toward a better tailored and sex-specific approach to the treatment of RLS associated with PLMS, with dopamine agonist possibly associated with a better outcome in females than in males.

Risk of Suicidal Ideation and Behavior Following Early-Onset Idiopathic Restless Legs Syndrome Treatment.

PURPOSE: To estimate incidence rates of suicidal ideation and behavior following treatment initiation with gabapentinoids or dopamine agonists (DAs) in patients with newly diagnosed early-onset idiopathic restless legs syndrome (RLS) and to examine suicidal behavior risk, comparing between those receiving gabapentinoids and DAs. METHODS: A new user retrospective cohort study using MarketScan claims data from 2012 to 2019 was conducted. Exposures were monotherapy gabapentinoids or DAs initiated within 60 days of new RLS diagnosis. Three varying outcome measures of suicidality were examined and incidence rates were calculated for each. A log-binomial regression model the estimated relative risk (RR) of the outcomes with gabapentinoids. Propensity score weighting adjusted for baseline covariates, including age, substance use disorders, hyperlipidemia, antipsychotic use, hypnotic/sedative use, and mood stabilizer use, which were most imbalanced before weighting. RESULTS: The cohort included 6672 patients, with 4986 (74.7%) initiating a DA and 1686 (25.3%) initiating a gabapentinoid. Incidence rates for all outcome measures were higher in the gabapentinoid group (suicidality: 21.6 vs. 10.7 per 1000 person-years; suicidality with self-harm: 23.0 vs. 11.1 per 1000 person-years; overdose- and suicide-related events: 30.0 vs. 15.5 person-years). Associated risk of suicidality (adjusted RR, 1.27 [95% CI, 0.86-1.88]); suicidality with self-harm (adjusted RR, 1.30 [95% CI, 0.89-1.90]); or overdose- and suicide-related events (adjusted RR, 1.30 [95% CI, 0.93-1.80]) was not significant with gabapentinoids. CONCLUSIONS: Incidence rates for suicidal ideation and behavior were higher among the gabapentinoid group, although increased risk was not detected after adjustment. A possible signal cannot be ruled out given limitations of the data and rarity of the outcome.

Effect of dairy products fortified with vitamin d3 on restless legs syndrome in women with premenstrual syndrome, abdominal obesity and vitamin d deficiency: a pilot study.

BACKGROUNDS: Restless legs syndrome (RLS) is an unpleasant condition that affects the quality of life of patients. Its prevalence in increased in women with premenstrual syndrome (PMS). Vitamin D plays a key role in female reproduction through its impact on calcium homeostasis and neurotransmitters. We aimed to evaluate the effect of dairy products fortified with Vitamin D3 on RLS in women with PMS. MATERIALS AND METHODS: We conducted a 2.5-month, randomized, total-blinded clinical trial to evaluate the effectiveness of low-fat milk and yogurt fortified with vitamin D on RLS in women with PMS. Among 141 middle-aged women with abdominal obesity, 71 and 70 cases received fortified and non-fortified low-fat dairy products, respectively. All subjects completed a Symptoms Screening Tool (PSST) and RLS questionnaires. RESULTS: The results showed that in the women with severe PMS (PSST > 28), serum levels of vitamin D increased significantly following vitamin D fortification. The mean restless legs score in the severe PMS subgroup (PSST > 28) was significantly lower after the intervention (p < 0.05. Serum Vitamin D levels significantly differed between intervention and control groups in all individuals (PSST < 19, PSST 19-28, and PSST > 28) (p < 0.05), but no significant differences were found between RLS scores of the intervention and control groups in the three PMS subgroups (p > 0.05). CONCLUSION: Fortifying dairy products with vitamin D3 can increase the serum levels of vitamin D and reduce the RLS severity in women with severe PMS, but not in other groups.

Gender medicine and sleep disorders: from basic science to clinical research.

Several pivotal differences in sleep and sleep disorders are recognized between women and men. This is not only due to changes in hormonal balance during women's reproductive life, such as in pregnancy and menopause. Women are more likely to report insomnia and non-specific symptoms of apneas, such as fatigue or mood disturbance, compared to men. Thus, it is important for clinicians and researchers to take sex and gender differences into account when addressing sleep disorders in order to acknowledge the biology unique to women. We present a narrative review that delves into the primary sleep disorders, starting from basic science, to explore the impact of gender differences on sleep and the current status of research on women's sleep health.

Current and emerging pharmaceutical strategies for the treatment and management of restless legs syndrome.

INTRODUCTION: Restless legs syndrome (RLS) is a sensory-motor sleep disorder that affects up to 13% of adults in the Western world and 2-4% of children. It impairs night sleep with an impact on daily performances and life quality. Thus, moderate-to-severe RLS requires pharmacological treatment. AREAS COVERED: In the present review, which is based on PubMed searches with no time limits, the authors discuss the recommended pharmacotherapy for RLS in addition to other emerging treatment options. The authors provide coverage to the current recommendations for both adults and pediatric patients with RLS. EXPERT OPINION: Current evidence suggests removing all causes of secondary RLS, including iron deficiency, chronic renal failure, drugs, and treating other sleep disorders that may worsen symptoms. Also, intermittent RLS should be addressed with behavioral measures and on-demand therapy. For chronic persistent RLS, α2δ calcium channel ligands are a first-line pharmacological approach, whereas dopamine agonists are associated with increased risk and should be spared. When RLS is refractory to first-line treatment, polytherapy, or opioid monotherapy should be considered. Nonetheless, some patients may not reach sustained symptom relief. Further research is needed to better understand the pathophysiology of RLS and to develop newer more effective drugs.

Effects of Dietary Supplementation in Patients with Restless Legs Syndrome: A Systematic Review.

Restless legs syndrome (RLS) is a common neurological disorder. It disrupts sleep and well-being and is often associated with other conditions. This review examines the potential of dietary supplements to manage RLS symptoms and reduce reliance on medications. A total of 10 randomized clinical trials involving 482 participants were analyzed, focusing on the impact of various supplements on symptom severity, sleep quality, and daytime sleepiness. Findings suggest some supplements may have positive results. Magnesium oxide and vitamin B6 significantly improved sleep quality and RLS symptoms, with magnesium showing greater effectiveness. Vitamin D supplementation did not show significant benefits. Oral iron has promising results, indicating potential efficacy but issues related to compliance and absorption. Both vitamins C and E positively affect RLS symptoms, likely due to their antioxidant properties. Valerian improved RLS and sleep but did not show a statistically significant improvement. Despite these encouraging results, a high risk of bias was noted in half of the studies, emphasizing the need for more rigorous research. Overall, this review suggests that dietary supplements may be a promising approach to managing RLS. However, further investigation is required to confirm the efficacy and safety.

Prevalence of depression or depressive state in patients with restless legs syndrome: A systematic review and meta-analysis.

Restless legs syndrome (RLS) is a common sleep-related disorder characterized by limb discomfort and the urge to move them when at rest, especially in the evening or at night. Although depression is often linked to various conditions, no systematic review has assessed depression prevalence in patients with RLS after the latest diagnostic criteria revision. This systematic review and meta-analysis aimed to investigate the depression and depressive state prevalence among patients with RLS. We systematically searched databases up to November 2022 and performed meta-analyses of the depression prevalence using a random-effects model and a meta-regression analysis to explore the relationship between the prevalence and severity of depression and factors such as age and RLS severity. Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines, we analyzed 24 studies with 2039 patients. The pooled depression or depressive state prevalence, mostly defined by questionnaire scores, was 30.39 %. Nine studies reported the proportion of patients taking antidepressants (pooled rate: 3.41 %). No specific factors related to the prevalence or severity of depression were identified in patients with RLS. These findings highlight the significant prevalence of depression and underscore the need for future research with standardized diagnostic interviews and consistent methodologies across multi-site studies.

Unfolding the role of exercise in the management of sleep disorders.

Sleep disorders are prevalent among the general population and even more in individuals suffering from chronic diseases. Recent data reveal promising effects of physical exercise as a non-pharmacological approach for improving sleep and managing various sleep disorders. However, more studies with proper design and methodology should be conducted in the future to obtain a clearer understanding of the subject. The role of exercise in preventing and improving sleep disorders is probably much higher than what is currently exploited. To fully exploit the potential benefit of physical activity on sleep disorders in the future, it is necessary to identify the relevant tools to assess sleep-wake disorders and establish specific exercise protocols tailored to different sleep disorders. The present manuscript aims to review the literature on the use of exercise in managing selected sleep disorders. Regular exercise, including short-term aerobic activity, resistance training, and mind-body exercises, can effectively improve sleep quality, particularly in cases of insomnia and sleep-disordered breathing. Additionally, increasing evidence supports the effectiveness of aerobic and strength training, and body-mind exercises such as yoga in managing sleep-related movement disorders. Exercise can be a safe, affordable, and efficient tool in enhancing sleep quality and improving sleep disorders. Per se, regular exercise could play an adjuvant role alongside with established therapies, or a valid alternative when the pharmacological approach is limited by side effects, interactions, or inefficacy. More research is needed to define how exercise affects the physiology of sleep, and consequently how to use exercise in patients with sleep disorders.

Diagnosis and management of common sleep disorders during the perinatal period.

The perinatal period is a critical phase in a woman's life characterized by significant physical, emotional, and societal changes. Sleep disorders such as insomnia, restless legs syndrome, obstructive sleep apnea, and poor sleep quality have been observed to increase in prevalence during the perinatal period. Given the harmful impact of sleep disturbances on the health of both mother and newborn, it is crucial to diagnose and treat them promptly. There is a paucity of literature on sleep problems during the perinatal period. This narrative review aimed to summarize the existing evidence and provide suggestions for promptly identifying and managing these disorders.

Prevalence and clinical profile of patients with restless legs syndrome in Parkinson's disease: A meta-analysis.

INTRODUCTION: Restless legs syndrome (RLS) is a sensorimotor disorder of sleep/wake regulation characterized by an urge to move the legs accompanied by a wide range of sensory symptoms, mainly affecting the lower limbs. An increased incidence of RLS has been demonstrated in Parkinson's disease (PD) and has been associated with severe motor and non-motor manifestations. We aimed to provide a reliable estimate of RLS prevalence and the clinical features associated with its occurrence in PD (PD-RLS). METHODS: We performed a systematic literature search up to January 2024 using PubMed, Scopus, and PsycINFO databases. Articles were included if they provided data on PD patients with or without RLS, and these proportions were used to estimate the prevalence of PD-RLS. Clinical profile associated with PD-RLS was explored by comparing the clinical characteristics of PD patients with and without RLS. RESULTS: Forty-six studies were included in the meta-analysis. Pooled RLS prevalence was 20 % of a total sample of 6990 PD patients and was associated with female sex, mixed motor phenotype, worse motor disturbances and functional disability, and a wide range of non-motor symptoms such as sleep disorders, cognitive and autonomic dysfunctions, and more severe neuropsychiatric manifestations. Sensitivity analyses indicated significant associations of PD-RLS with variables related to dopaminergic therapy. No association was found with serum ferritin, serum iron and hemoglobin levels. CONCLUSIONS: The prevalence of PD-RLS exceeds that reported in the general population, suggesting the existence of a relationship between the two disorders. Dopaminergic treatment seems to play an ambivalent role relieving, worsening or "mimicking" RLS manifestations. However, the clinical profile of PD-RLS patients, characterized by a greater severity of non-motor symptoms, also suggests that neurotransmitter systems other than the dopaminergic one are involved in PD-RLS etiology.

Exacerbation of restless legs syndrome following amygdalohippocampectomy: A case report.

Background: Restless legs syndrome (RLS) is a neurological sensorimotor disorder characterized by an uncontrollable urge to move the legs. In the perioperative period, patients with RLS may experience an acute exacerbation of symptoms. Although studies on the exacerbation of RLS after brain surgery are limited, we present a case wherein symptoms worsened following left amygdalohippocampectomy. Case Presentation: A 58-year-old woman diagnosed with mesiotemporal lobe epilepsy accompanied by left hippocampal sclerosis underwent a left amygdalohippocampectomy. The patient reported uncomfortable sensations in the lower limbs preoperatively. However, the urge to move her legs was manageable and not distinctly diagnosed with RLS. The symptoms began to deteriorate on the fifth postoperative day primarily affecting the legs and back, with a notable emphasis on the right side. Pramipexole treatment effectively ameliorated these symptoms. Conclusion: No reports are available highlighting the exacerbation of RLS after amygdalohippocampectomy. Perioperative factors, such as anesthesia and iron deficiency due to hemorrhage, have been proposed as aggravating factors for RLS; however, the asymmetry of RLS, particularly the atypical right-sided exacerbation in this case, makes it unlikely that this was the primary cause. A negative correlation between opioid receptor availability in the amygdala and RLS severity has been reported, suggesting that amygdalohippocampectomy contributes to the exacerbation of RLS symptoms. This case provides valuable insights into the possible involvement of the amygdala in the pathophysiology of RLS and practical considerations for the clinical management of the condition.

[Sleep disorders in patients with medication-overuse headache]. / Narusheniya sna u bol'nykh s lekarstvenno-indutsirovannoi golovnoi bol'yu.

OBJECTIVE: To analyze complaints about sleep disorders and assess the incidence of various sleep disorders, using relevant scales, in patients with medication-overuse headache (MOH) in comparison with patients without MOH. MATERIAL AND METHODS: The prospective case-control study included 171 patients, aged 18 years and older, with MOH (main group), and173 patients with primary headaches without MOH (control group). A neurologist conducted an initial examination and professional interview before the start of treatment. To diagnose sleep disorders, the International Classification of Sleep Disorders (3rd edition, 2014) was used. Additionally, an assessment was made using the Insomnia Severity Index Scale, the Epworth Sleepiness Scale (ESS) and the Lausanne Obstructive Sleep Apnea Syndrome Scale (NoSAS). RESULTS: Statistically significant differences were revealed in the prevalence of the following complaints about sleep disorders in patients with MOH: lack of sleep (51.5%), frequent awakenings during sleep (43.3%), discomfort in legs before falling asleep or at rest in the evening (37.4%). Difficulties falling asleep occurred equally often in both patients with MOH (43.9%) and without MOH (37.0%), as well as daytime sleepiness (40.4% vs 36.4%) and the presence of snoring (13% of patients in each group). Patients with MOH were significantly more likely to suffer from chronic insomnia (60.2% and 47.4%, respectively, p=0.02; OR 1.7; 95% CI 1.1-2.6) and restless legs syndrome (37.4% and 22.0%, respectively, p=0.002; OR 2.1; 95% CI 1.3-3.4). The incidence of hypersomnia and obstructive sleep apnea syndrome did not have statistically significant differences. CONCLUSION: Patients with MOH compared to patients without MOH have a significantly higher incidence of main complaints of sleep disorders, chronic insomnia and restless legs syndrome, which indicates the importance of sleep disorders in the pathogenesis of medication-overuse headaches and requires timely diagnosis and treatment to prevent the progression of both headaches and sleep disorders.

Sleep duration, napping behaviors and restless legs syndrome during pregnancy and the trajectories of ultrasonographic measures of fetal growth: Findings from the NICHD Fetal Growth Studies-Singletons.

OBJECTIVES: Given the plausible mechanisms and the lacking of empirical evidence, the study aims to investigate how gestational sleep behaviors and the development of sleep disorders, such as restless legs syndrome, influence ultrasonographic measures of fetal growth. METHODS: The study included 2457 pregnant women from the NICHD Fetal Growth Studies - Singletons (2009-2013), who were recruited between 8-13 gestational weeks and followed up to five times during pregnancy. Women were categorized into six groups based on their total sleep hours and napping frequency. The trajectory of estimated fetal weight from 10-40weeks was derived from three ultrasonographic measures. Linear mixed effect models were applied to model the estimated fetal weight in relation to self-reported sleep-napping behaviors and restless legs syndrome status, adjusting for age, race and ethnicity, education, parity, prepregnancy body mass index category, infant sex, and prepregnancy sleep-napping behavior. RESULTS: From enrollment to near delivery, pregnant women's total sleep duration and nap frequency declined and restless legs syndrome symptoms frequency increased generally. No significant differences in estimated fetal weight were observed by sleep-napping group or by restless legs syndrome status. Results remained similar in sensitivity analyses and stratified analyses by women's prepregnancy body mass index category (normal vs. overweight/obese) or by infant sex. CONCLUSIONS: Our data indicate that there is no association between sleep during pregnancy-assessed as total sleep duration and napping frequency, nor restless legs syndrome symptoms-and fetal growth from weeks 10 to 40 in healthy pregnant women.