Correlates of REM Sleep without Atonia in Dream Enactment Behavior Associated with Parkinson’s Disease

Introduction: Parkinson’s Disease (PD), a common neurodegenerative disease worldwide, has few reliable biomarkers. PD has been linked to REM Behavioral Disorder (RBD), a condition where patients abnormally experience REM sleep without atonia (RSWA). We aim to determine whether chin movements, a feature of RSWA, could serve as a PD biomarker. We hypothesize that those with higher RSWA are more likely to have PD. Methods: Our study examined patients who underwent polysomnograms from 2015 onwards at the Jefferson Sleep Disorders Center. We did a retrospective EPIC chart review and compared 2 groups, those with RBD and PD (n=12) versus RBD alone (n=25). While examining their polysomnographic data, %RSWA was calculated using AASM guidelines. Recursive partitioning algorithm was used to determine the %RSWA that correlated with the presence or absence of PD. Results: Patients with higher %RSWA were more likely to have PD as shown by the following data. RSWA \u3e20% was present in 11 patients, and had the highest correlation with PD (9/11). RSWA of 2.1% to 19.9% was present in 10 patients, and had modest correlation with PD (3/10). RSWA \u3c2.1% was present in 15 patients, and had the least correlation with PD (0/15). Discussion: Our results support our hypothesis indicating that RSWA, specifically chin movements, in RBD patients could serve as a PD biomarker. A larger cohort would need to be examined, however, this introduces the idea of routinely screening RBD patients for this and subsequently monitoring for PD symptoms. This could lead to earlier diagnosis and better prognosis

A short note on “Group theoretic approach to rationally extended shape invariant potentials” [Ann. Phys. 359 (2015) 46–54]

It is proved the equivalence of the compatibility condition of Ramos (2011, 2012) with a condition found in Yadav et al. (2015). The link of Shape Invariance with the existence of a Potential Algebra is reinforced for the rationally extended Shape Invariant potentials. Some examples on X1 and Xl Jacobi and Laguerre cases are given

Sleep oscillation-specific associations with Alzheimer’s disease CSF biomarkers : novel roles for sleep spindles and tau

Background: Based on associations between sleep spindles, cognition, and sleep-dependent memory processing, here we evaluated potential relationships between levels of CSF Aβ42, P-tau, and T-tau with sleep spindle density and other biophysical properties of sleep spindles in a sample of cognitively normal elderly individuals. Methods: One-night in-lab nocturnal polysomnography (NPSG) and morning to early afternoon CSF collection were performed to measure CSF Aβ42, P-tau and T-tau. Seven days of actigraphy were collected to assess habitual total sleep time. Results: Spindle density during NREM stage 2 (N2) sleep was negatively correlated with CSF Aβ42, P-tau and T-tau. From the three, CSF T-tau was the most significantly associated with spindle density, after adjusting for age, sex and ApoE4. Spindle duration, count and fast spindle density were also negatively correlated with T-tau levels. Sleep duration and other measures of sleep quality were not correlated with spindle characteristics and did not modify the associations between sleep spindle characteristics and the CSF biomarkers of AD. Conclusions: Reduced spindles during N2 sleep may represent an early dysfunction related to tau, possibly reflecting axonal damage or altered neuronal tau secretion, rendering it a potentially novel biomarker for early neuronal dysfunction. Given their putative role in memory consolidation and neuroplasticity, sleep spindles may represent a mechanism by which tau impairs memory consolidation, as well as a possible target for therapeutic interventions in cognitive decline

Correlates of REM sleep without atonia in dream enactment behavior associated with Parkinson’s disease, medication use and obstructive sleep apnea

METHODS: We did a retrospective review of medical records and polysomnographic (PSG) data of patients with dream enactment behavior (DEB) from 2015 to 2020. REM sleep without atonia (RSWA) was scored according to the AASM rules, and %RSWA was calculated. RESULTS: Thirty-six patients with DEB were analyzed. Recursive partitioning algorithm was used to determine the %RSWA that correlated with the presence or absence of Parkinson’s disease (PD). RSWA \u3e=20% was present in 11 patients, and had the highest correlation with PD (9/11). RSWA of 2.1% to 19.9% was present in 10 patients, and had modest correlation with PD (3/10). RSWA= 18% yielded the maximum combined sensitivity of 75% and specificity of 91.7% for concurrent diagnosis of PD. Due to a small sample size, we could not determine the minimum amount of total REM sleep that gives power to RSWA \u3e=20% (RSWA20) in predicting the presence of PD. The PD group (7) had a mean RSWA of 33.3%. The SSRI/SNRI group (4) had a mean RSWA of 26%. Patients who had PD and were on SSRI/SNRI (5) had a mean RSWA of 21%. The sleep apnea group (8) had a mean RSWA of 8.9%. Patients with DEB, but without PD, sleep apnea, and not on SSRI/SNRI (7) had a mean RSWA of 5.4%. A generalized linear regression analysis on the entire cohort revealed that patients on SSRI/SNRI (14) have 2.767 times higher %RSWA than those not on the medication (95% CI 1.393-5.497, p = .004). CONCLUSION: Among patients with dream enactment behavior, a diagnosis of PD and SSRI/SNRI use had the highest %RSWA on PSG, 33.3% and 26% respectively. Patients on SSRI/SNRI had 3 times higher %RSWA than those not on the medication

The Association between Health Conditions in World Trade Center Responders and Sleep-Related Quality of Life and Sleep Complaints

Background: World Trade Center (WTC) dust-exposed subjects have multiple comorbidities that affect sleep. These include obstructive sleep apnea (OSA), chronic rhinosinusitis (CRS), gastroesophageal-reflux disorder (GERD) and post-traumatic stress disorder (PTSD). We examined the impact of these conditions to sleep-related outcomes. Methods: Demographics, co-morbidities and symptoms were obtained from 626 WTC (109F/517M), 33–87years, BMI = 29.96 ± 5.53 kg/m2) subjects. OSA diagnosis was from a 2-night home sleep test (ARESTM). Subjective sleep quality, sleep-related quality of life (QOL, Functional Outcomes of Sleep Questionnaire), excessive daytime sleepiness (Epworth Sleepiness Scale), sleep duration and sleep onset and maintenance complaints were assessed. Results: Poor sleep quality and complaints were reported by 19–70% of subjects and average sleep duration was 6.4 h. 74.8% of subjects had OSA. OSA diagnosis/severity was not associated with any sleep-related outcomes. Sleep duration was lower in subjects with all conditions (p < 0.05) except OSA. CRS was a significant risk factor for poor sleep-related QOL, sleepiness, sleep quality and insomnia; PTSD for poor sleep-related QOL and insomnia; GERD for poor sleep quality. These associations remained significant after adjustment for, age, BMI, gender, sleep duration and other comorbidities. Conclusions: Sleep complaints are common and related to several health conditions seen in WTC responders. Initial interventions in symptomatic patients with both OSA and comorbid conditions may need to be directed at sleep duration, insomnia or the comorbid condition itself, in combination with intervention for OSA

A short note on “Group theoretic approach to rationally extended shape invariant potentials” [Ann. Phys. 359 (2015) 46–54]

It is proved the equivalence of the compatibility condition of [A. Ramos, J. Phys. A 44 (2011) 342001, Phys. Lett. A 376 (2012) 3499] with a condition found in [Yadav et al., Ann. Phys. 359 (2015) 46]. The link of Shape Invariance with the existence of a Potential Algebra is reinforced for the rationally extended Shape Invariant potentials. Some examples on X1 and Xl Jacobi and Laguerre cases are given.Comment: 10 pages, Latex, No figures,Version to appear in Annals of Physic