Association between periodic limb movements during sleep and neuroimaging features of cerebral small vessel disease: A preliminary cross-sectional study.

Evidence on the relationship between periodic limb movements during sleep (PLMS) and cerebral small vessel disease is lacking. This study aimed to assess the association between the PLMS index and the neuroimaging features of cerebral small vessel disease on magnetic resonance imaging. Consecutive patients diagnosed with cerebral small vessel disease were enrolled. Data on the clinical characteristics, polysomnography, and brain magnetic resonance imaging were collected. The Accubrain software was used to calculate automatically the volume of white matter hyperintensities, the number of lacunar infarctions, and cerebral microbleeds. The severity of white matter hyperintensities, enlarged basal ganglia perivascular spaces, and the total cerebral small vessel disease scores were also rated visually using semiquantitative scales. The severity of PLMS was measured using the PLMS index, and the patients were divided into two groups using an established cut-off value of ≥15 per hour. Logistic regression was used to examine the association between PLMS and the neuroimaging features of cerebral small vessel disease. In total, 37 patients were included in the final analyses. The mean age was 66.49 ± 11.31 years, and 73.0% were males. The mean PLMS index was 19.30 ± 10.18. In univariate analyses, it was found that patients with cerebral small vessel disease with a PLMS index ≥15 had increased enlarged basal ganglia perivascular spaces (OR 6.136, 95%CI 1.101-34.214) and increased total cerebral small vessel disease scores (OR 6.0, 95%CI 1.253-28.742). Only the association between the PLMS index and the total cerebral small vessel disease burden score remained statistically significant after adjusting for age, sex, and the presence of moderate to severe obstructive sleep apnea syndrome. In conclusion, an elevated PLMS index is likely to be associated with a greater cerebral small vessel disease burden. PLMS might be a novel potential marker of cerebral small vessel disease.

Clinical characteristics of periodic limb movements during sleep categorized by continuous positive airway pressure titration polysomnography in patients with obstructive sleep apnea.

PURPOSE: The presence of periodic limb movements during sleep (PLMS) varies among patients with obstructive sleep apnea (OSA) undergoing treatment with continuous positive airway pressure (CPAP). The factors associated with this variation are unknown. METHODS: PLMS were defined as a periodic leg movements index of > 15/h. Patients with OSA and PLMS were categorized into four groups depending on diagnostic and CPAP titration polysomnography (PSG). A multinomial logistic regression analysis was performed using a non-PLMS group as the reference category. RESULTS: This study included 861 patients with OSA who underwent a full-night CPAP titration PSG. The proportions of the subjects with PLMS on both PSGs (persistent PLMS), those with CPAP-emergent PLMS, and those with CPAP-resolved PLMS were 12.9%, 9.2%, and 3.9%, respectively. Compared with the non-PLMS group, the persistent group was more likely to be of older age and male sex and has a higher body mass index and restless legs syndrome (RLS). Patients in the CPAP-emergent group were also older and more likely to have RLS as well as more severe apnea. Patients in the CPAP-resolved group were more likely to be women, of older age, have a higher body mass index, but less severe apnea. CONCLUSIONS: PLMS elicited by CPAP are more likely to occur in older patients with more severe sleep apnea and comorbid RLS, whereas OSA patients in which PLMS resolve after CPAP are more likely to be women and have milder sleep apnea. Persistent PLMS share clinical characteristics with PLMS in general population.

Periodic limb movements during sleep are associated with poor health-related quality of life in patients with obstructive sleep apnea.

PURPOSE: The clinical significance of the comorbidity of periodic limb movements during sleep (PLMS) in sleep-disordered breathing remains unclear. This study aimed to determine whether or not the presence of PLMS is related to depressed mood and poor quality of life in subjects with obstructive sleep apnea (OSA). METHODS: We defined PLMS as a periodic leg movement index of > 15/h. Scores for the Medical Outcomes Study Short Form Health Survey and Beck Depression Inventory were assessed with multiple logistic or linear regression analyses. RESULTS: Of 1370 subjects with OSA, a prevalence of PLMS was 14.1%. Older age, men, and obesity were positively associated with PLMS. PLMS occurred in 17%, 15%, and 12% of mild, moderate, and severe subjects with OSA, respectively. Severe OSA was less likely to be associated with PLMS than mild OSA. PLMS negatively correlated with physical and mental component summary scores of the health survey but not with Beck Depression Inventory scores after controlling for confounding variables. PLMS were significantly associated with poor sleep architecture on polysomnography. However, the relationship between PLMS and disturbed sleep was no longer significant after adjusting for age. CONCLUSIONS: Health-related quality of life, including physical and mental health but not depressive symptoms, was worse in subjects with OSA and PLMS than in those without PLMS.

Periodic limb movements during sleep may reduce excessive daytime sleepiness in men with obstructive sleep apnea.

PURPOSE: The impact of periodic limb movements during sleep (PLMS) on excessive daytime sleepiness (EDS) is controversial. We investigated the relationship between PLMS and EDS in men with obstructive sleep apnea (OSA). METHODS: This was a cross-sectional study of men with OSA. PLMS parameters were a PLM index (PLMI) > 15 per hour of sleep and a PLM-arousal index (PLMAI) > 5 per hour of sleep. The Epworth Sleepiness Scale (ESS) and the Beck Depression Inventory were used. EDS was defined as an ESS score ≥ 11. Multivariate logistic regression analysis was performed with adjustments for several covariates. RESULTS: Of 1111 men with OSA, 14.0% (n = 156) had a PLMI > 15/h, and 3.7% (n = 41) had a PLMAI > 5/h. EDS was noted in 39.5% (n = 439) of men. Men with a PLMI > 15/h were less likely to have EDS (odd ratio [OR], 0.598; 95% confidence interval [CI], 0.414-0.864; p = 0.006). This association remained significant after controlling for age, body mass index, depressive symptoms, total sleep time, and severity of OSA (OR, 0.675; 95% CI, 0.456-0.999; p = 0.049). Men with a PLMAI > 5/h were less likely to have EDS, but this result did not reach statistical significance (OR, 0.550; 95% CI, 0.273-1.109; p = 0.095). CONCLUSIONS: PLMS defined as PLMI > 15/h are significantly and inversely associated with EDS in men with OSA, even after controlling for several confounding variables.

Lack of Association between Periodic Limb Movements during Sleep and Neuroimaging Signatures of Cerebral Small Vessel Disease in Stroke-Free Community-Dwelling Older Adults. The Atahualpa Project.

BACKGROUND: Evidence of the relationship between periodic limb movements during sleep (PLMS) and cerebral small vessel disease (cSVD) is limited and inconsistent. Here, we aimed to assess the independent association between PLMS and the different neuroimaging signatures of cSVD. METHODS: Atahualpa residents aged more than or equal to 60 years enrolled in the Atahualpa Project undergoing polysomnography and MRI with time intervals less than or equal to 6 months were included. MRI readings focused on white matter hyperintensities (WMH) of presumed vascular origin, deep cerebral microbleeds (CMB), silent lacunar infarcts (LI), and more than 10 enlarged basal ganglia-perivascular spaces (BG-PVS). Data from single-night polysomnograms were interpreted according to recommendations of the American Academy of Sleep Medicine. Associations between the PLMS index and neuroimaging signatures of cSVD (as dependent variables) were assessed by means of logistic regression models, adjusted for relevant confounders. RESULTS: A total of 146 individuals (mean age: 71.4 ± 7.5 years; 64% women) were included. A PLMS index more than or equal to 15 per hour were noted in 48 (33%) participants. Moderate-to-severe WMH were present in 33 individuals (23%), deep CMB in 9 (6%), silent LI in 16 (11%), and more than 10 BG-PVS in 44 (30%). In univariate analyses, silent LI (P = .035) and the presence of more than 10 enlarged BG-PVS (P = .034) were significantly higher among participants with a PLMS index more than or equal to 15 per hour. However, fully-adjusted multivariate models showed no significant association between PLMS index more than or equal to 15 per hour and any of the neuroimaging signatures of cSVD. CONCLUSIONS: This study shows no independent association between the PLMS index and neuroimaging signatures of cSVD in stroke-free community-dwelling older adults.

Periodic limb movements during sleep are associated with cardiovascular diseases: A systematic review and meta-analysis.

Periodic limb movements during sleep present with repetitive movements, typically in the lower limbs, during sleep. Periodic limb movements during sleep have been proposed to be associated with increased risk of heart diseases. The aim of this study was to examine the co-morbidity rates of heart disease, including acute myocardial infarction, coronary artery disease and cardiovascular disease, in subjects with or without periodic limb movements during sleep through a meta-analysis. An electronic review of PubMed, Embase, ScienceDirect, Cochrane Library, ProQuest, Web of Science, ClinicalKey and ClinicalTrials.gov was performed. Clinical studies, case-controlled trials and cohort studies were all included in the search. Case reports or series, and non-clinical studies were excluded. A meta-analysis of the results of six studies comparing the prevalence of coronary artery disease/acute myocardial infarction/cardiovascular disease in subjects with/without periodic limb movements during sleep was performed. There were significantly higher co-morbidity rates of coronary artery disease (odds ratio = 1.568, 95% confidence interval: 1.187-2.073, p = 0.002) and cardiovascular disease (odds ratio = 1.279, 95% confidence interval: 1.095-1.494, p = 0.002), but not acute myocardial infarction (odds ratio = 1.272, 95% confidence interval = 0.942-1.718, p = 0.117), in the periodic limb movements during sleep group than in the non-periodic limb movements during sleep group. This meta-analysis highlights the importance of a significantly high prevalence of coronary artery disease and cardiovascular disease in subjects with periodic limb movements during sleep. Further studies should be focused on the potential pathophysiology, and whether treatment for periodic limb movements during sleep can improve the outcome of heart disease.

Interaction effect of obstructive sleep apnea and periodic limb movements during sleep on heart rate variability.

We aimed at assessing cardiac autonomic function by heart rate variability during sleep in patients with obstructive sleep apnea and periodic limb movements during sleep, and to compare it with that of patients with obstructive sleep apnea only, periodic limb movements during sleep only, and controls. We also aimed at investigating the interaction effect between apnea-hypopnea index and periodic limb movement index on heart rate variability. Four groups of patients (n = 42 each, total = 168) were identified based on the presence/absence of obstructive sleep apnea and periodic limb movements during sleep: + obstructive sleep apnea/- periodic limb movements during sleep (5 ≤ apnea-hypopnea index < 30 events per hr), - obstructive sleep apnea/+ periodic limb movements during sleep (periodic limb movement index > 15 events per hr), + obstructive sleep apnea/+ periodic limb movements during sleep, - obstructive sleep apnea/- periodic limb movements during sleep (controls). All groups were matched for age, sex and body mass index. Time- and frequency-domain heart rate variability measures were calculated over 5-min periods of stable stage 2 non-rapid eye movement sleep. In patients with both obstructive sleep apnea and periodic limb movements during sleep, LFnu and LF/HF ratio were higher than in those with obstructive sleep apnea only, periodic limb movements during sleep only, and controls, while HFnu was the lowest among the four groups. LFnu, HFnu and LF/HF ratio were significantly and independently associated with minimal oxygen saturation in the + obstructive sleep apnea/+ periodic limb movements during sleep group. There was a significant interaction effect between apnea-hypopnea index and periodic limb movement index on LF/HF ratio (p = 0.038) in patients with obstructive sleep apnea. Patients with elevated apnea-hypopnea index and elevated periodic limb movement index exhibited higher sympathovagal balance compared with those with high apnea-hypopnea index and low periodic limb movement index, and compared with those with low apnea-hypopnea index (regardless of periodic limb movement index). Increased sympathetic activation and decreased parasympathetic control appear to be related to the severity of oxygen desaturation. Apnea-hypopnea index and periodic limb movement index had interactive effects on increased sympathovagal balance in patients with obstructive sleep apnea.

[Effects of continuous positive airway pressure on periodic limb movements during sleep in patients with obstructive sleep apnea].

Objective: To investigate the effects of continuous positive airway pressure (CPAP) on periodic limb movements during sleep (PLMS) in patients with obstructive sleep apnea (OSA). Methods: The polysomnography (PSG) data of 828 consecutive OSA outpatients from January 2015 to January 2017 who had undergone overnight CPAP titration were analyzed retrospectively. On the basis of changes in periodic limb movements index (PLMI) values (cut off level≥15/h) from baseline PSG (BPSG) to CPAP titration PSG, patients were assigned to one of the following four groups: persistent, CPAP-emergent, CPAP-disappeared, and non-PLMS. Results: Among 828 patients, 756 (91.3%) were male and 72 (8.7%) were female. The mean age was (45.7±10.7) years old, the mean body mass index (BMI) was (27.6±3.5) kg/m(2). The rate of patients was 3.9% in the persistent group, 10.3% in the CPAP-emergent group, 7.5% in the CPAP-disappearance group, and 78.4% in the non-PLMS group. Multivariate Logistic regression analysis revealed that female appeared to be associated with the persistent group (P=0.004); older age and higher apnea-hypopnea index (AHI) on BPSG appeared to be associated with the CPAP-emergent group (P=0.012, 0.030). On the other hand, older age was negatively associated with the non-PLMS group (P=0.006). Conclusion: Elderly patients with higher AHI at BPSG may present with CPAP-emergent PLMS.

Nocturnal periodic limb movements decrease antioxidant capacity in post-stroke women.

OBJECTIVES: Considerable evidence suggests that periodic limb movements during sleep (PLMS) are associated with cardiovascular risk and poor stroke outcome. However, the pathogenesis for this association in stroke patients remains largely unknown. MATERIALS AND METHODS: This cross-sectional study enrolled 112 consecutive patients who were admitted to rehabilitation ward due to ischemic stroke. Polysomnography and laboratory tests for oxidative stress and inflammatory biomarkers including C-reactive protein, interleukin 6, total antioxidant capacity (TAC), and urinary 8-hydroxy-2-deoxyguanosine were conducted. RESULTS: Patients were stratified into three categories according to their PLMS index. Patients in the PLMS index ≥15 group were significantly older (P = 0.011), presented a significantly higher National Institute of Health Stroke Scale at stroke onset (P = 0.032), and lower Barthel index (P = 0.035) than patients in the PLMS index <5 group. The level of TAC differed significantly (P = 0.018) among the three groups. Multivariate linear regression analyses show that the PLMS index was negatively and independently correlated with TAC (P = 0.024) in women. Besides, multivariate logistic regression analyses also reveal that patients with a PLMS index ≥15 compared with the referent PLMS index <5 had a 7.58-fold increased relative hazard for stroke recurrence (odds ratio 7.58, [1.31-43.88], P = 0.024). CONCLUSIONS: This study suggests that PLMS was independently associated with decreased antioxidant capacity in women with ischemic stroke.

Long-term effects of caffeine therapy for apnea of prematurity on sleep at school age.

RATIONALE: Apnea of prematurity is a common condition that is usually treated with caffeine, an adenosine receptor blocker that has powerful influences on the central nervous system. However, little is known about the long-term effects of caffeine on sleep in the developing brain. OBJECTIVES: We hypothesized that neonatal caffeine use resulted in long-term abnormalities in sleep architecture and breathing during sleep. METHODS: A total of 201 ex-preterm children aged 5-12 years who participated as neonates in a double-blind, randomized, controlled clinical trial of caffeine versus placebo underwent actigraphy, polysomnography, and parental sleep questionnaires. Coprimary outcomes were total sleep time on actigraphy and apnea-hypopnea index on polysomnography. MEASUREMENTS AND MAIN RESULTS: There were no significant differences in primary outcomes between the caffeine group and the placebo (adjusted mean difference of -6.7 [95% confidence interval (CI) = -15.3 to 2.0 min]; P = 0.13 for actigraphic total sleep time; and adjusted rate ratio [caffeine/placebo] for apnea-hypopnea index of 0.89 [95% CI = 0.55-1.43]; P = 0.63). Polysomnographic total recording time and total sleep time were longer in the caffeine group, but there was no difference in sleep efficiency between groups. The percentage of children with obstructive sleep apnea (8.2% of caffeine group versus 11.0% of placebo; P = 0.22) or elevated periodic limb movements of sleep (17.5% in caffeine group versus 11% in placebo group) was high, but did not differ significantly between groups. CONCLUSIONS: Therapeutic neonatal caffeine administration has no long-term effects on sleep duration or sleep apnea during childhood. Ex-preterm infants, regardless of caffeine status, are at risk for obstructive sleep apnea and periodic limb movements in later childhood.

Association of Periodic Limb Movements and Obstructive Sleep Apnea With Risk of Cardiovascular Disease and Mortality.

BACKGROUND: Obstructive sleep apnea is a well-established risk factor for cardiovascular disease (CVD). Recent studies have also linked periodic limb movements during sleep to CVD. We aimed to determine whether periodic limb movements during sleep and obstructive sleep apnea are independent or synergistic factors for CVD events or death. METHODS AND RESULTS: We examined data from 1049 US veterans with an apnea-hypopnea index (AHI) <30 events/hour. The primary outcome was incident CVD or death. Cox proportional hazards regression assessed the relationships between the AHI, periodic limb movement index (PLMI), and the AHI×PLMI interaction with the primary outcome. We then examined whether AHI and PLMI were associated with primary outcome after adjustment for age, sex, race and ethnicity, obesity, baseline risk of mortality, and Charlson Comorbidity Index. During a median follow-up of 5.1 years, 237 of 1049 participants developed incident CVD or died. Unadjusted analyses showed an increased risk of the primary outcome with every 10-event/hour increase in PLMI (hazard ratio [HR], 1.08 [95% CI, 1.05-1.13]) and AHI (HR, 1.17 [95% CI, 1.01- 1.37]). Assessment associations of AHI and PLMI and their interaction with the primary outcome revealed no significant interaction between PLMI and AHI. In fully adjusted analyses, PLMI, but not AHI, was associated with an increased risk of primary outcome: HR of 1.05 (95% CI, 1.00-1.09) per every 10 events/hour. Results were similar after adjusting with Framingham risk score. CONCLUSIONS: Our study revealed periodic limb movements during sleep as a risk factor for incident CVD or death among those who had AHI <30 events/hour, without synergistic association between periodic limb movements during sleep and obstructive sleep apnea.

Periodic limb movements during sleep and risk of hypertension: A systematic review.

BACKGROUND: Several studies suggest an association between periodic limb movements during sleep (PLMS) and hypertension; however, a systematic evaluation of this relationship is lacking. METHODS: We conducted a systematic review and meta-analysis of observational studies that reported odds ratio, relative risk, hazard ratio, or standardized incidence ratio, comparing the risk of hypertension in persons with PLMS (defined by the level of periodic limb movements per hour of sleep depended on individual studies) versus those without PLMS. After assessing heterogeneity and bias, the pooled risk ratio and 95% confidence intervals (CIs) were determined using a random-effect, generic inverse variance method of DerSimonian and Laird. RESULTS: Out of 572 potentially relevant articles, six eligible studies were included in the data analysis. Studies (6 cross-sectional) included 8949 participants. The statistical heterogeneity of this study was insignificant, with an I2 of 0%. A funnel plot and Egger's regression asymmetry test showed no publication bias with P-value ≥0.05. The pooled risk ratio of hypertension in patients with PLMS was 1.26 (95% CI, 1.12-1.41). CONCLUSIONS: Our analysis demonstrates an increased hypertension risk among patients with PLMS. Prospective or interventional studies are needed to confirm this association.

Pharmacological responsiveness of periodic limb movements in patients with restless legs syndrome: a systematic review and meta-analysis.

STUDY OBJECTIVES: Periodic limb movements during sleep (PLMS) are a frequent finding in restless legs syndrome, but their impact on sleep is still debated, as well the indication for treatment. We systematically reviewed the available literature to describe which drug categories are effective in suppressing PLMS, assessing their efficacy through a meta-analysis, when this was possible. METHODS: The review protocol was preregistered on PROSPERO (CRD42021175848), and the systematic search was conducted on and EMBASE (last searched on March 2020). We included original human studies, which assessed PLMS modification on drug treatment with a full-night polysomnography, through surface electrodes on each tibialis anterior muscle. When at least 4 studies were available on the same drug or drug category, we performed a random-effect model meta-analysis. RESULTS: Dopamine agonists like pramipexole and ropinirole resulted the most effective, followed by l-dopa and other dopamine agonists. Alpha2delta ligands are moderately effective as well opioids, despite available data on these drugs are much more limited than those on dopaminergic agents. Valproate and carbamazepine did not show a significant effect on PLMS. Clonazepam showed contradictory results. Perampanel and dypiridamole showed promising but still insufficient data. The same applies to iron supplementation. CONCLUSIONS: Dopaminergic agents are the most powerful suppressors of PLMS. However, most therapeutic trials in restless legs syndrome do not report objective polysomnographic findings, there is a lack of uniformity in presenting results on PLMS. Longitudinal polysomnographic interventional studies, using well-defined and unanimous scoring criteria and endpoints on PLMS are needed. CITATION: Riccardi S, Ferri R, Garbazza C, Miano S, Manconi M. Pharmacological responsiveness of periodic limb movements in patients with restless legs syndrome: a systematic review and meta-analysis. J Clin Sleep Med. 2023;19(4):811-822.

Periodic Limb Movements during Sleep in Acute Stroke: Prevalence, Severity and Impact on Post-Stroke Recovery.

BACKGROUND: Periodic Limb Movements during Sleep (PLMS) have been described to be frequently present in stroke patients. We aimed to evaluate the prevalence and severity of PLMS in acute stroke patients and clarify the association between PLMS and coexisting Sleep Disordered Breathing (SDB). Additionally, we focused on identifying variables that could independently predict the presence of PLMS in patients with acute stroke. The potential impact of PLMS on stroke outcome at three months was investigated as well. METHODS: In this study, we performed overnight polysomnography on consecutive stroke patients within 72 h from symptom onset. Data regarding clinical and imaging characteristics were prospectively collected. National Institute of Health Stroke Scale (NIHSS), modified Rankin Scale (mRS) and Epworth-Sleepiness Scale (ESS) were used to evaluate stroke severity on admission, stroke outcome at three months and history of daytime sleepiness, respectively. We documented PLMS and SDB using standard polysomnography criteria. RESULTS: We prospectively assessed 126 patients with acute stroke [109 with ischemic and 17 with hemorrhagic stroke, mean age 60 ± 11 years, 68% men, median NIHSS score on admission: 3 (IQR: 2-7)]. The overall rate of PLMS in our cohort was 76%, and the rate of SDB among patients with PLMS was 83%. PLMS detection rates differed significantly (p-value: <0.001) according to SDB, with PLMS prevalence increasing with greater SDB severity. SDB could independently (OR:4.869, 95% CI: 1.884-12.784, p-value: 0.001) predict the presence of PLMS in the acute stroke phase in multivariable analyses adjusting for potential confounders. Moreover, baseline stroke severity (NIHSS-score increase in per-1 point: OR: 0.819, 95% CI: 0.737-0.895, p-value < 0.001) and PLMS (OR:0.099, 95% CI: 0.009-0.482, p-value = 0.015) were significantly associated with the likelihood of excellent functional outcome (mRS-scores: 0-1) at 3 months. CONCLUSION: The common presence of mostly severe PLMS in patients with acute stroke and their negative effect on stroke outcomes point out the necessity for early PLMS detection and treatment.

Spinal cord stimulation in severe pharmacoresistant restless legs syndrome-two case reports.

Restless legs syndrome is a prevalent, sleep-related sensorimotor disorder with relevant impact on the patients' quality of life. For patients suffering from severe, pharmacoresistant restless legs syndrome, few therapeutic options remain to alleviate symptoms. In this case series, two patients with severe, pharmacoresistant restless legs syndrome were treated with epidural spinal cord stimulation and repeatedly assessed with polysomnography, including sleep structure and periodic limb movements as objective biomarkers not subject to placebo effects, during a 6-month follow-up period. One of the patients experienced excellent short- and long-term efficacy on subjective symptom severity (International RLS Study group rating scale 1 vs. 34 points at 3 months) and objective sleep parameters such as sleep architecture and periodic limb movements during sleep, while the second patient only reported short-term benefits from spinal cord stimulation. Ultimately, both patients opted for removal of the device for inefficacy. Based on the complex pathophysiology of restless legs syndrome and presumed mechanism of action of spinal cord stimulation in chronic pain disorders, we provide a detailed hypothesis on the possible modulating effect of spinal cord stimulation on the key symptoms of restless legs syndrome. Apart from describing a new therapeutic option for pharmacoresistant restless legs syndrome, our findings might also provide further insights into the pathophysiology of the syndrome.

Sleep Disorders and Sleep Problems in Patients With Tourette Syndrome and Other Tic Disorders: Current Perspectives.

Sleep disorders seem to be a frequent complaint of patients diagnosed with Tourette syndrome (TS) or chronic or persistent tic disorders (CTD or PTD). In this review, we expanded a previously used search using 4 well-known databases up to February 15, 2022, looking for the coexistence of global and/or specific sleep disorders and polysomnographic studies performed on patients with TS/CTD/PTD. The references of interest in the topic were selected by hand. Sleep disorders in general, insomnia, different arousal disorders, the persistence of tics during sleep, excessive daytime sleepiness, and periodic limb movements during sleep (PLMS) were very frequent in patients with TS, most of them being more frequent in patients with comorbid Attention Deficit Hyperactivity Disorder. The most frequent results from polysomnographic studies were decreased sleep efficiency and increased sleep onset latency. Many of these findings could be related to medication used for the treatment of tics and comorbid disorders.

Sex Differences in Excessive Daytime Sleepiness Among Patients With Obstructive Sleep Apnea.

BACKGROUND AND PURPOSE: To identify sex differences in daytime sleepiness associated with apnea severity and periodic limb movements during sleep (PLMS) in subjects with obstructive sleep apnea (OSA). METHODS: This study used the Epworth Sleepiness Scale (ESS), Beck Depression Inventory (BDI), and Sleep Hygiene Index (SHI) in logistic regression analyses with interaction terms. Severe OSA, excessive daytime sleepiness (EDS), and PLMS were defined as an apnea-hypopnea index of ≥30, an ESS score of ≥11, and a periodic limb movements index of >15, respectively. RESULTS: The 1,624 subjects with OSA (males, 79.1%) comprised 45.3%, 38.2%, and 16.4% with severe OSA, EDS, and PLMS, respectively. Multiple logistic regression without interaction terms showed that sex, severe OSA, and PLMS were not significantly associated with EDS. However, significant interactions were noted between sex and severe OSA and PLMS in EDS in both crude and adjusted models (all p values<0.05). In the adjusted model, severe OSA was associated with EDS in males (p=0.009) but not in females. PLMS were more likely to be associated with EDS in females (p=0.013), whereas PLMS were less likely to be associated with EDS in males (p=0.041). The models were adjusted by the BDI score, SHI, and presence of medical comorbidities. CONCLUSIONS: There are significant sex differences in subjective daytime sleepiness in subjects with severe OSA and PLMS. Severe OSA and PLMS may influence daytime sleepiness more in males and females, respectively.

Different scoring rules for respiratory event-related leg movements: effects on the prevalence of periodic limb movements during sleep and their association with depressive symptoms in patients with obstructive sleep apnea.

BACKGROUND: We compared the prevalence of periodic leg movements during sleep (PLMS) according to two different scoring rules of the American Academy of Sleep Medicine (AASM) 2012 and World Association of Sleep Medicine (WASM) 2016 and determined their association with depressed mood in patients with obstructive sleep apnea (OSA). METHODS: PLMS, defined as a periodic leg movements index of >15, were diagnosed on a diagnostic and continuous positive airway pressure (CPAP) titration polysomnography using the AASM 2012 and WASM 2016 rules. The Beck Depression Inventory (BDI) and Epworth Sleepiness Scale (ESS) were used, and multiple regression analyses were performed. RESULTS: Among 160 OSA patients, the proportion with PLMS scored by the WASM 2016 criteria was significantly higher than that scored by the AASM 2012 criteria in a diagnostic study (20.6% vs. 16.3%, respectively; P = 0.016) but not in CPAP titration study and only in patients with severe OSA. In adjusted models, PLMS were positively associated with BDI scores and a BDI of ≥10 on both diagnostic and CPAP titration studies when scored by the WASM 2016. By contrast, when scored by the AASM 2012, PLMS were associated with BDI scores (but not BDI of ≥10) only in a CPAP titration study. CONCLUSIONS: There are significant differences in the prevalence of PLMS and their association with depressed mood depending on the scoring rules in patients with OSA. The current AASM scoring criteria underestimate the prevalence of PLMS, and PLMS are more likely associated with depressed mood according to the WASM scoring criteria.

Sleep disorders in tourette syndrome.

Sleep disorders are very common in patients diagnosed with Tourette syndrome (TS). The present review focuses on sleep disorders and the results of polysomnographic studies performed in patients with TS. We made a search using the PubMed, Embase, MedLine, and Web of Science Databases, from 1966 until November 14, 2019, crossing the search term "Tourette syndrome" with "sleep", "sleep disorders", "sleep disturbances", and "polysomnography", and with each of the specific sleep disorders listed according to the International Classification of the Sleep Disorders-Third Edition. Then we identified the references of interest for the topic. Insomnia, excessive daytime sleepiness, disorders of arousal (sleepwalking, sleeptalking, sleep terrors, and enuresis), the persistence of tics during sleep, and presence of periodic limb movements during sleep (PLMS) were very frequent in patients with TS. These disturbances were more frequent in children and in patients with comorbid Attention Deficit Hyperactivity Disorder. Decreased sleep efficiency, decreased percentage of delta sleep, increased nocturnal awakenings and increased PLMS were the most consistent findings in the polysomnographic studies.

Images: Periodic Limb Movements During Sleep Noted on Ventral Thigh Surface Electromyography in an Above-the-Knee Amputated Stump.

None: Ventral thigh surface electromyography may be used to assess for periodic limb movements during sleep (PLMS) in a limb with an above-the-knee amputation. Presence of PLMS in the proximal portion of an amputated lower extremity supports theories of spinal and supraspinal mechanisms in PLMS generation, and demonstrates that intact distal motor efferent pathways and distal sensory afferent pathways are not absolutely necessary for the generation of periodic limb movements. CITATION: Chada A, Hoque R. Periodic limb movements during sleep noted on ventral thigh surface electromyography in an above-the-knee amputated stump. J Clin Sleep Med. 2019;15(8):1183-1184.