Periodic Limb Movements Research Articles

Periodic limb movements during sleep in children with neuromuscular disease or cerebral palsy – An important potential contributor to sleep-related morbidity

ObjectivesPoor sleep is frequently reported in children with neuromuscular diseases (NMD) and cerebral palsy (CP) however breathing disorders during sleep are often the clinical focus. Periodic limb movements (PLMs) have an increased prevalence in adults with NMD and may contribute to sleep disturbance in this population. We assessed the prevalence of PLMs in children with NMD or CP. MethodsRetrospective review of polysomnography (PSG) with leg electromyography in children age 1–18 years with NMD (including Duchenne muscular dystrophy, myotonic dystrophy, spinal muscular atrophy) or CP performed at a paediatric sleep centre 2004–2022. ResultsLeg electromyography was available in at least 1 PSG in 239 children (125 NMD, 114 CP), and in 2 PSGs in 105 children (73 NMD, 32 CP). At initial PSG, 72 (30 %) were female with a median age 9y and respiratory disturbance index 3.5/h (interquartile range 1.3–9.9/h). Elevated PLM index (PLMI; >5/h) occurred in 9.6 % of each of the CP and NMD groups, quantified by initial PSG. Overall, PLMI increased from baseline (median 0, maximum 33/h) to follow-up (median 0, maximum 55.8/h; p < 0.05). In those with an elevated PLMI, arousal percentage attributable to PLMs was up to 25 % (median 7.5 %). ConclusionsElevated PLMI occurred at a higher prevalence in children with NMD and CP than reported in other clinic-referred paediatric populations. It is important that PLMs are not overlooked as identification and treatment may help improve sleep outcomes. Further research is required to understand the pathophysiology and consequences of PLMs specifically in this population.

Sleep After Concussion: A Scoping Review of Sensor Technologies.

Sleep disturbances following a concussion/mild traumatic brain injury are associated with longer recovery times and more comorbidities. Sensor technologies can directly monitor sleep-related physiology and provide objective sleep metrics. This scoping review determines how sensor technologies are currently used to monitor sleep following a concussion. We searched Ovid (Medline, Embase), Web of Science, CINAHL, Compendex Engineering Village, and PsycINFO from inception to June 20, 2022, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for scoping reviews. Included studies objectively monitored sleep in participants with concussion. We screened 1081 articles and included 37 in the review. A total of 17 studies implemented polysomnography (PSG) months to years after injury for a median of two nights and provided a wide range of sleep metrics, including sleep-wake times, sleep stages, arousal indices, and periodic limb movements. Twenty-two studies used actigraphy days to weeks after injury for a median of 10 days and nights and provided information limited to sleep-wake times. Sleep stages were most reported in PSG studies, and sleep efficiency was most reported in actigraphy studies. For both technologies there was high variability in reported outcome measures. Sleep sensing technologies may be used to identify how sleep affects concussion recovery. However, high variability in sensor deployment methodologies makes cross-study comparisons difficult and highlights the need for standardization. Consensus on how sleep sensing technologies are used post-concussion may lead to clinical integration with subjective methods for improved sleep monitoring during the recovery period.

Polysomnographically Defined Restless Sleep Disorder and Periodic Limb Movements during Sleep in Children Born Prematurely.

Children born prematurely (<37 weeks' gestation) are at increased risk of perinatal complications, comorbidities, and iron deficiency. Iron deficiency is associated with restless legs syndrome and periodic limb movement disorder. In this study, we assessed the prevalence of restless sleep disorder (RSD) and elevated periodic limb movements during sleep (PLMS) in children born prematurely who underwent polysomnography. A retrospective chart review of sleep studies was conducted in children aged 1-18 years (median age 4 years) with a history of premature birth. Children with genetic syndrome, airway surgery, or tracheostomy were excluded. Three groups were compared: children with PLMS index >5, children with RSD, and children with neither elevated PLMS index nor RSD. During the study, 2577 sleep studies were reviewed. Ninety-two studies fit our criteria and were included in the analysis. The median age at birth was 31 weeks, and the interquartile range (IQR) was 27-34 weeks. A total of 32 (34.8%) children were referred for restless sleep and 55 (59.8%) for snoring. After polysomnography, 18% were found to have a PLMS index >5/h, and 14% fit the criteria for restless sleep disorder (RSD). There were no statistically significant differences in PSG parameters among the children with RSD, PLMS, and the remaining group, except for lower obstructive apnea/hypopnea index (Kruskal-Wallis ANOVA 8.621, p = 0.0135) in the RSD group (median 0.7, IQR 0.3-0.9) than in the PLMS (median 1.7, IQR 0.7-3.5) or the non-RSD/non-PLMS (median 2.0, IQR 0.8-4.5) groups. There was an elevated frequency of RSD and elevated PLMS in our cohort of children born prematurely. Children born prematurely are at higher risk of iron deficiency which can be a contributor factor to sleep -related movement disorders. These results add new knowledge regarding the prevalence of RSD and PLMS in these children.

Wearable-Based Integrated System for In-Home Monitoring and Analysis of Nocturnal Enuresis.

Nocturnal enuresis (NE) is involuntary bedwetting during sleep, typically appearing in young children. Despite the potential benefits of the long-term home monitoring of NE patients for research and treatment enhancement, this area remains underexplored. To address this, we propose NEcare, an in-home monitoring system that utilizes wearable devices and machine learning techniques. NEcare collects sensor data from an electrocardiogram, body impedance (BI), a three-axis accelerometer, and a three-axis gyroscope to examine bladder volume (BV), heart rate (HR), and periodic limb movements in sleep (PLMS). Additionally, it analyzes the collected NE patient data and supports NE moment estimation using heuristic rules and deep learning techniques. To demonstrate the feasibility of in-home monitoring for NE patients using our wearable system, we used our datasets from 30 in-hospital patients and 4 in-home patients. The results show that NEcare captures expected trends associated with NE occurrences, including BV increase, HR increase, and PLMS appearance. In addition, we studied the machine learning-based NE moment estimation, which could help relieve the burdens of NE patients and their families. Finally, we address the limitations and outline future research directions for the development of wearable systems for NE patients.

Positional obstructive sleep apnea and periodic limb movement during sleep: A large multi-center study.

The relationships among positional obstructive sleep apnea (POSA), obstructive sleep apnea (OSA), and periodic limb movement during sleep (PLMS) are unclear. We analyzed these relationships according to OSA severity and explored the underlying mechanisms. We retrospectively reviewed 6,140 eligible participants who underwent full-night diagnostic polysomnography in four clinical centers over a period of 5 years with eventsynchronized analysis. The PLMS index (PLMI) and periodic limb movements with arousal index (PLMAI) were evaluated. The effects of POSA on the PLMI, PLMAI, and PLMS were analyzed according to OSA severity. The mean PLMI and PLMAI, as well as PLMS prevalence, were significantly lower in those with severe OSA than in those with mild and moderate OSA. The mean PLMI was higher in mild OSA group than in control group. The mean PLMI (4.80 ± 12.71 vs. 2.59 ± 9.82 events/h, p < 0.001) and PLMAI (0.89 ± 3.66 vs. 0.53 ± 3.33 events/h, p < 0.001), and the prevalence of PLMS (11% vs. 5.3%, p < 0.001) were higher in patients with POSA than patients with non-POSA. This trend was particularly marked in severe OSA group (OR 1.55, 95%CI [1.07-2.27]) and less so in mild (OR 0.56, 95%CI [0.30-1.03]) and moderate (OR 1.82, 95%CI [0.99-3.34]) OSA groups. The POSA group tended to have a higher prevalence of PLMS, particularly in those with severe OSA. If PLMS is prominent, diagnosis and treatment of POSA and OSA may be considered.

A Historical Overview of the Role of Benzodiazepines including Clonazepam in the Treatment of Adult Restless Legs Syndrome and Periodic Limb Movements in Sleep.

Benzodiazepines are frequently used as therapy in Restless Legs Syndrome (RLS) and Periodic Limb Movements in Sleep. The order of benefit is Sleep>RLS>PLMS and arousals > PLMS. For clonazepam dosages of 0.5 mg-2.0 mg/day are most frequently employed. Benzodiazepines exert their therapeutic effect through GABA-ergic mechanisms.

Periodic limb movements in sleep: evolving role of autonomic nervous system.

Periodic limb movements in sleep: evolving role of autonomic nervous system.

Effect of series of periodic limb movements in sleep on blood pressure, heart rate and high frequency heart rate variability.

The phenomenon known as periodic limb movements in sleep (PLMS) has been linked to a change in autonomic nervous system (ANS) activity and its effect on circulatory regulation. Autonomic dysfunction or dysregulation in patients with PLMS has been described in some domains; however, any relationship between heart rate variability (HRV) and PLMS has not been clearly established. HRV analysis is a recognised, non-invasive research method that describes the influence of the ANS on heart rate (HR). The aim of our study was to further investigate the dysregulation of autonomic HR control in patients with PLMS. We undertook a retrospective analysis of the polysomnographic (PSG), demographic and medical data of five patients with a total number of 1,348 PLMS. We analysed HR, HRV HF, systolic blood pressure (SBP), and diastolic blood pressure (DBP) for 10 heartbeats before the series of PLMS and 10 consecutive heartbeats as beat-to-beat measurements. The presented method of using successive, short, 10 RR interval segments refers to the time-frequency measurement, which is very clear and useful for presenting changes in the calculated parameters over time and thereby illustrating their dynamics. This method allowed us to assess dynamic changes in HRV HF during successive PLMS series. Statistical analysis was performed using IBM SPSS Statistics (v. 28.0.0.0). The Kruskal-Wallis test was performed to find statistically significant changes from baseline. No statistically significant changes in HR, SBP, or DBP were found in our group, although an increase in the value of the HRV HF was noted, suggesting an increase in intracardiac parasympathetic activity during the subsequent series of PLMS. Our study indicates an increase in parasympathetic activity during the appearance of successive PLMS, which, with the simultaneous lack of changes in HR, may suggest an increase in sympathetic activity, and therefore the appearance of so-called 'autonomic co-activation' resulting in the possibility of life-threatening cardiac events. Our findings add to the literature information regarding HRV in PLMS, and highlight the need for further studies to elucidate the effects of these conditions on the ANS, and on cardiovascular health.

Periodic limb movements in patients with suspected obstructive sleep apnea without comorbid conditions.

Periodic limb movement disorder (PLMD) and obstructive sleep apnea (OSA) are overlapping clinical syndromes with common risk factors. However, current literature has failed to establish a clear pathophysiological link between them. Thus, little is known about periodic limb movements (PLM) in otherwise healthy patients with suspected OSA. We performed a retrospective analysis of 112 patients (age: 44.5 ± 12.0 years, 14.3% female) with suspected OSA who underwent full night polysomnography for the first time. Patients with chronic diseases of any kind, recent infections, malignancies, or daily or regular use of any type of medication were excluded. Group comparisons were made based on the severity of OSA (using the apnea hypopnea index, AHI) or the periodic limb movement index (PLMI). Both, PLMI and the total number of periodic limb movements during sleep (PLMS), showed a significant increase in patients with severe OSA. In addition, AHI and apnea index (AI) were significantly higher in patients with PLMI >15/h, with a similar trend for hypopnea index (HI) (p < 0.001, p < 0.001, and p > 0.05, respectively). PLMI was significantly positive correlated with AHI, AI, and HI (r = 0.392, p < 0.001; r = 0.361, p < 0.001; and r = 0.212, p < 0.05, respectively). Patients with PLMI >15/h were significantly older (p < 0.001). There was no significant association between body mass index (BMI) and PLMI >15/h. We found a significant association between the severity of OSA and PLM in our study population with suspected OSA but without other comorbidities. PLMI and PLMS were significantly increased in patients with severe OSA. Future prospective studies with larger collectives should verify the presented results and should include mechanistic aspects in their evaluation.

Manual scoring of periodic limb movements in children: is it still necessary?

ObjectiveAlthough manual scoring has been classically considered the gold standard to identify periodic leg movements (PLM), it is a very time consuming and expensive process, also subject to variability in interpretation. In the last decades, different authors have observed reasonably good agreement between automated PSG scoring algorithms and manual scoring in adults, according to established criteria. We aim to compare the automatic software analysis of our polysomnogram with the manual staging in children with sleep-disordered breathing. MethodsWe performed a semiautomatic method, in which an experienced technician watched the video recording and removed from the automatic analysis those movements that did not correspond to true candidate leg movement (LM). ResultsA total of 131 PSGs were studied; applying the established criteria, 65 children were diagnosed of obstructive sleep apnea, and 66 presented snoring but with no sleep apnea. The mean age was 6.7 years (±1.7) and twenty-five children (19.08 %) had a PLMI >5/h. Statistical differences were found not only for PLMI (manual: 2.20 (0.7, 4.1) vs automatic (6.4 (3.85,9.5); p < 0.001), but for almost of all indexes assessed between the automatic and the manual scoring analysis. The level of concordance was only moderate for PLM index (0.63 [0.51–0.72]); showing that, unlike the articles published in the adult population, automatic analysis is not accurate in children and, manually or semi-automatically analysis as ours need to be done. ConclusionIt seems that PLM detection algorithm might work accurately but, the real need would be a true LM detection algorithm.

1190 Periodic Limb Movement Disorder Masked by Concurrent Focal Aware Seizures

1190 Periodic Limb Movement Disorder Masked by Concurrent Focal Aware Seizures

0705 Detection of Periodic Limb Movements During Sleep in RLS Using Tonic Motor Activation System and Machine Learning

0705 Detection of Periodic Limb Movements During Sleep in RLS Using Tonic Motor Activation System and Machine Learning

0695 Residual Periodic Limb Movement Index After CPAP Titration Is Correlated with Hypoxemia

0695 Residual Periodic Limb Movement Index After CPAP Titration Is Correlated with Hypoxemia

0808 Nighttime Distribution of Periodic Limb Movements of Sleep After Surgical OSA Treatment in Pediatric Population

0808 Nighttime Distribution of Periodic Limb Movements of Sleep After Surgical OSA Treatment in Pediatric Population

Elevated periodic limb movement index is associated with hypoxemia in children with early onset scoliosis.

Patients with early onset scoliosis are at high risk of sleep disordered breathing, sleep disruption, and adverse consequences of poor sleep. In this study, we aim to assess the prevalence of periodic limb movements of sleep in a cohort of children with early onset scoliosis and identify factors that correlate with the presence of periodic limb movements. This is a retrospective chart review of 40 patients with EOS (ages 1-17years) who underwent a PSG from 2003 through 2019. Data collected included age, sex, and polysomnography parameters. Descriptive statistics were used: independent T test and Pearson correlation. The average age was 9.6years (SD 5.2); 22 were female. Eleven patients (27.5%) had elevated periodic limb movement index (PLMI) (≥ 5). Those with PLMI ≥ 5 had arousal index of 15.4 (SD 7.2) and those with normal PLMI having an arousal index of 9.4 (SD 4.9); this reached statistical significance (p < 0.05). Those with elevated PLMI spent 4.9 (SD 8.3) minutes with saturations below 88%, while those with normal PLMI spent 1.0 (SD 1.8); this was statistically significant. There was a moderate positive correlation between arousal index, hypoxemia, and PLMI. The study suggests that children with early onset scoliosis have higher frequency of periodic limb movements during sleep, and these may be correlated with increased arousal and with hypoxemia.

Sleep Disorder and its Treatment: From Nature to Laboratory

Sleep is the natural cellular repair mechanism to improve and restore central neural mechanism, memory, hormonal imbalance, and finally, cell rejuvenation. Sleep disorder is characterized by insomnia, circadian rhythm disorder (CRD), sleep apnea, narcolepsy, parasomnia, and restless leg syndrome (RLS) or periodic limb movement disorder (PLMD). Both oversleeping and less sleeping are associated with sleep disorders (SD). Anxiety, schizophrenia, weight loss/gain, hypothyroidism, and oxidative stress are the most common outcomes of SD. There is also a genetic explanation behind circadian rhythmicity, circadian disorder, narcolepsy-cataplexy syndrome, fatal familial insomnia, and somnambulism. Excessive work pressure, stress, and consumption of caffeine and alcohol collectively push a person toward sleep deprivation. Anxiety, schizophrenia, weight loss/gain, hypothyroidism, and oxidative stress are the most common outcomes of SD. Adenosine, melatonin, dopamine, serotonin, gamma amino butyric acid (GABA), orexin, and histamine regulate SDs by various pathways. Among natural sources, Centella asiatica, Bacopa monnieri, Acorus calamus, Withania somnifera, Nardostachys jatamansi, Poria cocos is, Valeriana officinalis, Matricaria chamomilla, Lavandula angustifolia, Nelumbo nucifera, Melissa officinalis, Convolvulus pluricaulis, Camellia sinensis, Ziziphus jujube, Datura stramonium, Zhizhipus jujube, Passiflora incarnata, and Moringa oleifera showed remarkable effects on different forms of SDs through GABAA, serotonin, and melatonin receptors. Pramipexole, ropinirole, rotigotine, clonazepam, lorazepam, estazolam, zolpidem, lemborexant, daridorexant, and suvorexant showed its activity in the treatment of SDs as a dopamine agonist, inhibitor of GABAA receptor, dual orexin receptor antagonist, respectively. This article focused on the types of SDs, the effects of SDs on mental health, receptors involved in the sleep cycle, and the impact of natural molecules and synthetic molecules in the management of SDs.

Compromised Dynamic Cerebral Autoregulation in Patients with Restless Legs Syndrome.

Restless legs syndrome (RLS) is a prevalent sensorimotor nervous system disorder in patients accompanied with insomnia, blood pressure fluctuation, and sympathetic dysfunction. These symptoms may disrupt cerebral hemodynamics. Dynamic cerebral autoregulation (dCA) describes the temporary response of cerebrovascular system to abrupt fluctuations in blood pressure, which keep cerebral blood flow stable and serve as a marker of cerebrovascular system ability. This research aimed to assess dCA in RLS patients. In this study, RLS patients were recruited and subsequently classified into four groups (mild, moderate, severe, and very severe) based on the International RLS Rating Scale (IRLS). Healthy controls matched for age and sex were enrolled. All participants were evaluated dCA by assessing phase difference (PD). A portion of patients with RLS was reassessed for dCA after one month of medication therapy (pramipexole [0.125 mg/day] and gabapentin [300 mg/day]). There were altogether 120 patients with RLS and 30 controls completed the polysomnography and dCA assessment. PD was lower in the moderate, severe, and very severe RLS groups than that in the controls and mild RLS groups. Periodic limb movement index (PLMI), arousal index, and IRLS all showed a linear correlation with PD in RLS patients. Additionally, PD increased in RLS patients after therapy. The dCA was compromised in moderate, severe, and very severe RLS patients and was negatively correlated with the IRLS, arousal index, and PLMI. After 1 month of therapy, dCA improved in RLS patients.

Restless legs syndrome variants: A systematic review

IntroductionRestless Legs Syndrome (RLS) is a clinical syndrome that may manifest itself in non-leg parts of the body as well, called RLS variant, which is considered a distinct entity by some researchers. In this systematic review, we tried to evaluate various clinical features and effective treatments of RLS variants and compare them with that of typical RLS. MethodsThis study was conducted following the PRISMA guideline. The primary search was performed in the data resources of Medline (PubMed), Web of Science, and Scopus, as well as the Google Scholar search engine. The required data were extracted from the studies. ResultsIn this review, 1565 studies were initially identified and finally 39 studies were selected. The most common RLS variants were observed to involve hands, head, abdomen, and genitalia. These patients mostly complained of sleep disturbance and feelings of itching, tingling and twitching. Supportive diagnostic criteria of RLS including familial history of RLS, periodic limb movements during sleep (PLMS) and response to treatment with dopaminergic agents were assessed. ConclusionIt seems that patients with RLS variant can undergo the same diagnostic and therapeutic work-up as patients with conventional RLS. It is suggested that these two disorders fall into the same syndromic spectrum.

Sleep related movement disorders in the elderly: a review of recent literature

Sleep-related movement disorders (SRMD) are common, often troublesome, conditions in the elderly. Although these disorders can impact people of all ages, there are different considerations when diagnosing and managing SRMD in the elderly. In this review, we discuss SRMD in the elderly, focusing on recent developments in the areas of restless leg syndrome, periodic limb movement disorder, nocturnal muscle cramps, and sleep-related bruxism. In addition to reviewing these entities more generally, we highlight key considerations in addressing these in conditions in older adults.

Coexistence of periodic limb movements during sleep with restless legs syndrome and its association with hypertension in Japanese patients

BackgroundCaucasian patients with restless legs syndrome (RLS) frequently exhibit periodic limb movements during sleep (PLMS), which may increase the risk of hypertension. We evaluated the positivity rate of PLMS and factors associated with positivity in Japanese patients with RLS, and tested whether the complications of PLMS are associated with the presence of hypertension. MethodsWe retrospectively investigated polysomnographic data and the presence or absence of hypertension in patients with RLS. Patients with systolic blood pressure ≥140 mmHg or diastolic blood pressure ≥90 mmHg or those taking antihypertensive medication were categorized as the group with hypertension. ResultsAmong 468 patients, 200 (42.7%) had periodic limb movement index (PLMI) values ≥ 15/h and 108 (23.1%) met the criteria of positivity for hypertension. Multiple logistic regression analysis revealed that only higher age was significantly associated with PLMI values ≥ 15/h. Multiple linear regression analyses of factors associated with an increased PLMI also showed that increased PLMI was significantly correlated with higher age and male sex, but not with the international restless legs scale scores. Multiple logistic regression analysis also revealed that higher age and body mass index, not PLMI values ≥ 15/h, were significantly associated with the presence of hypertension. ConclusionThe PLMS-positivity rate may be lower in Japanese patients with RLS than in Caucasian patients, and it increases with age and male sex, but not with the severity of the disorder. Furthermore, PLMS complications were not associated with the risk of hypertension in Japanese patients with RLS.