Dream Enactment Behavior Research Articles

Clinical and Laboratory Features Predict Phenoconversion from Sporadic Adult-onset Ataxia to Multiple System Atrophy.

To determine predicting factors and frequency of phenoconversion from sporadic adult-onset ataxia (SAOA) to multiple system atrophy (MSA). We performed a retrospective review of all patients referred for cerebellar ataxia from 1998 to 2018 at Mayo Clinic, Minnesota. We analyzed clinical features, autonomic testing, and imaging for predictors of later diagnosis of MSA. Among 169 patients with ataxia at presentation, 60 (35.5%) phenoconverted to MSA. Clinical features in MSA phenoconverters included: early autonomic symptoms, stridor, and dream enactment behavior. Imaging features in phenoconverters included pontine atrophy and hot cross bun sign. On autonomic testing, MSA phenoconverters had higher supine blood pressures with larger drops, higher median composite autonomic severity scores, and higher percentage anhidrosis than patients with SAOA. Our findings show that at least a third of patients with SAOA phenoconverted to MSA. Clinical features, autonomic testing, and imaging at presentation may be helpful to identify such patients.

Nightmares in the elderly: Associations with self-reported executive functions

Study objectivesTo describe nightmare phenomenology among community dwelling elderly and to test the hypothesis that reduction in cognitive control is associated with nightmare-related phenomenology including nightmare frequency and severity, greater emotional reactivity, imagery immersion, and dream enactment behaviors (DEBs). MethodsStudy 1: Survey with multiple regression and ANOVAs on N = 56 people with frequent nightmares plus N = 62 age- and gender-matched controls to quantify the strength of the association between cognitive control variables and nightmare phenomenology. Study 2: Computational simulation of nightmare phenomenology in relation to cognitive control to simulate the empirical findings and to assess the underlying causal theory through computationally supported causal inference. ResultsStudy 1: Regressions demonstrated a strong association between reduction in cognitive control and more extreme nightmare phenomenology, including severity, frequency, daytime effects, and DEBs. Study 2: The computational simulation of nightmare phenomenology in relation to cognitive control is validated relative to regressions from study 1 and offers computational support for the causal theory explaining the associations in study 1. ConclusionsIn aging people, decline in executive cognitive functions, cognitive control, and inhibitory processes reduce cognitive control over emotions, thus contributing to unusual nightmare activity, including more extreme nightmare phenomenology such as more severe nightmares, greater emotional reactivity, deeper imagery immersion, and DEBs.

Opportunities and Pitfalls of REM Sleep Behavior Disorder and Olfactory Dysfunction as Early Markers in Parkinson's Disease.

During its pre-motor stage, Parkinson's disease (PD) presents itself with a multitude of non-motor symptoms with different degrees of specificity and sensitivity. The most important among them are REM sleep behavior disorder (RBD) and olfactory dysfunction. RBD is a parasomnia characterized by the loss of REM sleep muscle atonia and dream-enacting behaviors. Olfactory dysfunction in individuals with prodromal PD is usually described as hyposmia (reduced sense of smell) or anosmia (complete loss of olfactory function). These symptoms can precede the full expression of motor symptoms by decades. A close comprehension of these symptoms and the underlying mechanisms may enable early screening as well as interventions to improve patients' quality of life. Therefore, these symptoms have unmatched potential for identifying PD patients in prodromal stages, not only allowing early diagnosis but potentially opening a window for early, possibly disease-modifying intervention. However, they come with certain challenges. This review addresses some of the key opportunities and pitfalls of both RBD and olfactory dysfunction as early markers of PD.

Cerebellum and basal ganglia connectivity in isolated REM sleep behaviour disorder and Parkinson's disease: an exploratory study.

REM sleep behaviour disorder (RBD) is a parasomnia characterised by dream-enacting behaviour with loss of muscle atonia during REM sleep and is a prodromal feature of α-synucleinopathies like Parkinson's disease, dementia with Lewy bodies, and multiple system atrophy. Although cortical-to-subcortical connectivity is well-studied in RBD, cerebellar and subcortical nuclei reciprocal connectivity is less established. Nonetheless, it could be relevant since RBD pathology involves brainstem structures with an ascending gradient. In this study, we utilised resting-state functional MRI to investigate 13 people with isolated RBD (iRBD), 17 with Parkinson's disease and 16 healthy controls. We investigated the connectivity between the basal ganglia, thalamus and regions of the cerebellum. The cerebellum was segmented using a functional atlas, defined by a resting-state network-based parcellation, rather than an anatomical one. Controlling for age, we found a significant group difference (F4,82 = 5.47, pFDR = 0.017) in cerebellar-thalamic connectivity, with iRBD significantly lower compared to both control and Parkinson's disease. Specifically, cerebellar areas involved in this connectivity reduction were related to the default mode, language and fronto-parietal resting-state networks. Our findings show functional connectivity abnormalities in subcortical structures that are specific to iRBD and may be relevant from a pathophysiological standpoint. Further studies are needed to investigate how connectivity changes progress over time and whether specific changes predict disease course or phenoconversion.

Polysomnographic features prior to dream enactment behaviors in isolated rapid eye movement sleep behavior disorder

ObjectiveThis study aimed to identify electroencephalogram correlates of dream enactment behaviors (DEBs) and elucidate their cortical dynamics in patients with isolated/idiopathic rapid eye movement (REM) sleep behavior disorder (iRBD). MethodsThis cross-sectional study included 15 patients with iRBD. Two REM sleep periods in routine polysomnography were compared: the 60 s preceding the DEBs (“pre-representative behavior” [preR]), and the 60 s with the least submental electromyogram activity (“background” [BG]). Six EEG frequency bands and electrooculogram were analyzed; power spectra, coherence and phase-locking values in four 15-s periods were examined to assess trends. These indices were also compared between preR and BG. ResultsCompared with BG, significantly higher delta power in the F3 channel and gamma power in the F4 and O2 channels were observed during preR. For functional connectivity, the widespread beta-band connectivity was significantly increased during preR than BG. ConclusionBefore notable REM sleep behaviors, uneven distributed higher EEG spectral power in both very low and high frequencies, and increased wide-range beta band functional connectivity, were observed over 60 s, suggesting cortical correlates to subsequent DEBs. SignificanceThis study may shed light on the pathological mechanisms underlies RBD through the routine vPSG analysis, leading to detection of DEBs.

Challenges of Positive Airway Pressure Treatment for Patients With Obstructive Sleep Apnea at a Veterans Medical Center.

Positive airway pressure (PAP) compliance is important in treating obstructive sleep apnea. Previous studies have suggested that patients with economic burdens, discomfort using machines, and insufficient education have difficulty tolerating PAP machines. This study explored the factors affecting short-term adherence to PAP in a veterans medical center. The medical records of patients who underwent polysomnography at the Veterans Health Service Medical Center, Seoul, Republic of Korea, between July 2018 and January 2021 were reviewed retrospectively. Patients with an apnea-hypopnea index (AHI) ≥15 were included (n=579). PAP adherence was defined as continuous use for ≥21 days for ≥4 hours daily for 30 consecutive days for 90 days from the date of PAP prescription. The PAP-adherent group (n=265, age 66.16±11.28 years) was younger and had more years of education, higher body mass indices, and lower scores in the Insomnia Severity Index and Beck Depression Inventory-II (BDI-II) than those of the PAP-nonadherent group (n=314, age 68.93±10.91 years). Patients who tolerated PAP had a higher AHI, longer duration of oxygen desaturation (less than 90%), and less dream enactment behavior (DEB) than that in those who did not. After adjusting for age, years of education, BDI-II, duration of oxygen desaturation, and presence of DEB, there were more patients with National Health Insurance (NHI) in the PAP-adherent group than in the PAP-nonadherent group (p<0.001). We showed that patients with NHI recorded significantly higher adherence compared to that in patients without NHI, among other factors.

REM sleep and neurodegeneration.

Several brainstem, subcortical and cortical areas are involved in the generation of rapid eye movement (REM) sleep. The alteration of these structures as a result of a neurodegenerative process may therefore lead to REMsleep anomalies. REM sleep behaviour disorder is associated with nightmares, dream-enacting behaviours and increased electromyographic activity in REM sleep. Its isolated form is a harbinger of synucleinopathies such as Parkinson's disease or dementia with Lewy bodies, and neuroprotective interventions are advocated. This link might also be present in patients taking antidepressants, with post-traumatic stress disorder, or with a history of repeated traumatic head injury. REM sleep likely contributes to normal memory processes. Its alteration has also been proposed to be part of the neuropathological changes occurring in Alzheimer's disease.

Prodromal Status of Rapid Eye Movement Sleep Behavior Disorder: Clinical Significance and Future Perspectives

Rapid eye movement (REM) sleep behavior disorder (RBD) is a prodromal stage for major neurodegenerative diseases, particularly α-synucleinopathies. Recently, the spectrum of RBD is expanding and its prodromal state has been recognized and categorized into isolated REM sleep without atonia and isolated dream-enacting behavior. Although unclear, prodromal RBD frequently occurs in the aged population, with a significantly high phenoconversion rate to RBD and an increased risk of developing neurodegenerative disorders. More active and structured general surveillance of this condition may contribute to the effective modulation of major neurodegenerative diseases. However, the clinical and polysomnographic profiles of prodromal RBD, methods for effective screening and diagnosis of prodromal RBD, and biomarkers for disease progression and phenoconversion must be investigated.

Beta band functional connectivity increases prior to dream enactment behavior in patients with idiopathic/isolated REM sleep behavior disorder

Beta band functional connectivity increases prior to dream enactment behavior in patients with idiopathic/isolated REM sleep behavior disorder

Altered Impulsivity Across Drug-Naïve Parkinsonism, Isolated Rapid Eye Movement Sleep Behavior Disorder, and Their High-Risk Relatives.

To determine multidimensional impulsivity levels across different early stages of α-synucleinopathy. This cross-sectional study investigated motor and decisional impulsivity levels using a panel of computerized tasks among drug-naïve parkinsonism patients, isolated/idiopathic rapid eye movement sleep behavior disorder (iRBD) patients and their first-degree relatives (iRBD-FDRs), and control participants. Trait impulsivity and impulse control behaviors were assessed by self-reported questionnaires. A total of 27 drug-naïve parkinsonism patients, 157 iRBD patients, 66 iRBD-FDRs, and 82 control participants were recruited. Parkinsonism and iRBD patients had fewer numbers of extracted beads in beads task 1 and 2 (both p < 0.001), and a higher rate of irrational choice in task 1 (p = 0.046) before making decisions, and fewer numbers of pumps of unexploded blue balloons in the balloon analog risk task (p = 0.004) than control participants, indicating a higher level of reflection impulsivity and a lower level of risk taking, respectively. iRBD patients had more no-go errors in the go/no-go task than control participants (padjusted = 0.036), suggesting a higher level of motor impulsivity. iRBD-FDRs with dream-enactment behaviors had fewer numbers of extracted beads (p = 0.047) in beads task 2 than FDRs without dream-enactment behaviors, suggesting a possible higher level of reflection impulsivity. A complex construct of altered impulsivity with decreased risk taking, but increased reflection and motor impulsivity, has already occurred at the prodromal and early stages of α-synucleinopathy, which have implications for underlying pathophysiology and clinical management of α-synucleinopathy, especially for impulse control behaviors upon dopaminergic drug treatment. ANN NEUROL 2024;95:544-557.

Cardiac noradrenergic deficiency revealed by 18F-dopamine positron emission tomography identifies preclinical central Lewy body diseases.

In Lewy body diseases (LBDs) Parkinson disease (PD), and dementia with Lewy bodies (DLB), by the time parkinsonism or cognitive dysfunction manifests clinically, substantial neurodegeneration has already occurred. Biomarkers are needed to identify central LBDs in a preclinical phase, when neurorescue strategies might forestall symptomatic disease. This phase may involve catecholamine deficiency in the autonomic nervous system. We analyzed data from the prospective, observational, long-term PDRisk study to assess the predictive value of low versus normal cardiac 18F-dopamine positron emission tomography (PET), an index of myocardial content of the sympathetic neurotransmitter norepinephrine, in at-risk individuals. Participants self-reported risk factor information (genetics, olfactory dysfunction, dream enactment behavior, and orthostatic intolerance or hypotension) at a protocol-specific website. Thirty-four with 3 or more confirmed risk factors underwent serial cardiac 18F-dopamine PET at 1.5-year intervals for up to 7.5 years or until PD was diagnosed. Nine participants had low initial myocardial 18F-dopamine-derived radioactivity (<6,000 nCi-kg/cc-mCi) and 25 had normal radioactivity. At 7 years of follow-up, 8 of 9 with low initial radioactivity and 1 of 11 with normal radioactivity were diagnosed with a central LBD (LBD+) (P = 0.0009 by Fisher's exact test). Conversely, all 9 LBD+ participants had low 18F-dopamine-derived radioactivity before or at the time of diagnosis of a central LBD, whereas among 25 participants without a central LBD only 1 (4%) had persistently low radioactivity (P < 0.0001 by Fisher's exact test). Cardiac 18F-dopamine PET highly efficiently distinguishes at-risk individuals who are diagnosed subsequently with a central LBD from those who are not. gov NCT00775853. Division of Intramural Research, NIH, NINDS.

A Case of Intractable REM Sleep Behavior Disorder Improved With Nasal Continuous Positive Airway Pressure Therapy

Rapid eye movement (REM) sleep behavior disorder (RBD) is characterized by dream enactment behavior and REM sleep without atonia and is traumatic for the patient and/or bedpartner. Obstructive sleep apnea (OSA) is a common comorbidity of RBD, and several reports have suggested that severe OSA may aggravate RBD symptoms. This case report discusses a patient with medically intractable RBD combined with OSA, confirmed by 10-year follow-up polysomnography (PSG) data, which improved with nasal continuous positive airway pressure (CPAP) therapy. The clinical symptoms of RBD markedly improved after CPAP treatment. Clinicians should raise the clinical suspicion of OSA in patients with intractable RBD and consider follow-up PSG and OSA treatments.

The MAPT P.G324L and P.A406G mutations are associated with progressive supranuclear palsy with atypical features

IntroductionProgressive supranuclear palsy (PSP) is an atypical parkinsonism caused by the intracerebral aggregation of the microtubule-associated protein tau (MAPT) which is encoded by MAPT gene. Although PSP is a sporadic disease, MAPT mutations have been reported in rare cases. MethodsAmong 190 patients with PSP who were recruited by the Neurodegenerative Research Group at Mayo Clinic during 2009–2023, we identified two patients who fulfilled diagnostic criteria for PSP-Richardson's syndrome (PSP-RS) and harbor novel MAPT mutations. To better investigate the potential effects of these mutations, we compared the clinical, and neuroimaging characteristics of these two patients to 20 randomly selected patients with PSP-RS without a MAPT mutation. ResultsMAPT c.1024G > A, p. Glu342Lys, and MAPT c.1217 G > A, p. Arg406Gln mutations were found in 2 men who developed PSP-RS with atypical features at the ages of 60 and 62 years, respectively. Glu342Lys mutation was associated with features resembling alpha-synucleinopathies (autonomic dysfunction, dream enactment behavior), while both mutations were associated with features suggestive of Alzheimer's disease with poorer performance on tests of episodic memory. Comparison of 18F-flortaucipir uptake between the two MAPT mutation cases with 20 patients without a mutation revealed increased signal on flortaucipir-PET in bilateral medial temporal lobe regions (amygdala, entorhinal cortices, hippocampus, parahippocampus) but not in PSP-related regions (globus pallidum, midbrain, superior frontal cortex and dentate nucleus of the cerebellum). ConclusionGlu342Lys and Arg406Gln mutations appear to modify the PSP-RS phenotype by targeting the medial temporal lobe regions resulting in more memory loss and greater flortaucipir uptake.

Parasomnias manifest different phenotypes of sleep-related behaviors in age and sex groups. A YouTube-based video research highlighting the age slope of sleepwalking

Study objectiveFinding typical patterns - phenotypes - of sleep behaviors characterizing parasomnias in different age and sex groups. MethodsWe analyzed YouTube videos on sleep-related behaviors likely representing parasomnias. We applied the search terms “sleepwalking”, “somnambulism”, “sleep eating”, “sleep sex”, “sleep talking”, and “aggression in sleep” in six languages. We classified those persons shown on the videos into estimated biological sex and age (child, adult, elderly) groups. We scored the activity types by a self-made scale and applied binary logistic regression to analyze the association between sleep behaviors versus sex and age groups by the STATA package, providing a 95% confidence interval and the probability of statistical significance. Results224 videos (102 women, 68 children, 16 adults, and 40 elderly people) were scored. Elderly people had significantly (P < 0.012) lower odds of sleepwalking compared to adults and children. Adult females performed complex manual activities during sleepwalking more often than males (P < 0.012). Elderly males had 40-fold odds compared to adults and children, to perform aggressive movements and 70-fold odds of complex movements in bed, compared to adults. Elderly people presented emotional behaviors less frequently than adults (P < 0.004), and females showed them twice as often as males. Adults sleep-talked full sentences more often than children and elderly people (P < 0.001). ConclusionOur results support the existence of age- and sex-specific parasomnia phenotypes, denoting possible safety measures. The remarkably low odds of sleepwalking in the elderly highlight the possibility of different pathomechanisms in higher age groups compared to children. Brief Summary and study impactParasomnias present highly variable clinical forms and often cause injuries. Identifying typical phenotypes may help risk management and imply theoretical conclusions. Our study supports the existence of age-specific parasomnia phenotypes. We found that adult women have a high risk of performing dangerous activities during sleep, and elderly males often move violently in bed, likely representing dream enactment behaviors. Elderly people of both sexes have low odds of sleep ambulation- likely representing somnambulism; compared to adults and children, constituting a descending “age slope” of somnambulism that might reflect different underlying pathomechanisms in children versus adults and the elderly.

Characteristics of Recurrent Visions of the Nonphysical World Among Cognitively Unimpaired Elders of the Ojibwe Tribal Nation.

Visual hallucinations are a core feature of dementia with Lewy bodies and primary psychiatric disease, yet identification of a hallucination vs normal spiritual experience depends on cultural context. Almost no information exists in the medical literature regarding normal spiritual experiences in American Indian participants in the context of a neurocognitive evaluation. To assess the characteristics of a normal spiritual experience in an Ojibwe Tribal Nation. This prospective, cross-sectional study was conducted between August 1, 2021, and August 31, 2022, among an Ojibwe Tribal Nation in northern Minnesota. Participants were evaluated at their tribal nation clinic. Cognitively unimpaired tribal Elders who were enrolled members of the tribal nation and aged 55 years or older were invited to participate via fliers, radio advertisements, and health fair presentations. Thirty-seven tribal Elders volunteered. Each participant was asked whether they experienced hallucinations or visions of people, animals, or objects that are not part of the physical world. This was an a priori formulated question and part of a comprehensive neurocognitive evaluation consisting of history and physical examination (including cognitive screening with a subspecialty-trained behavioral neurologist); blood tests for metabolic, nutritional, and thyroid conditions; and noncontrast magnetic resonance imaging brain scan. Four patients were excluded from the present analysis due to having mild cognitive impairment or dementia. Thirty-three cognitively unimpaired tribal Elders (mean [SD] age, 66.0 [7.5] years; 22 women [67%]) were included. Sixteen (48%) answered affirmatively, reporting recurrent visions of the nonphysical world. Generally, these visions were well formed, benevolent in nature, and transient; started in preadolescence; involved spirits or ancestors; and were congruent with cultural and spiritual beliefs of the Ojibwe people. No patients had accompanying dream enactment behavior, dysautonomia, parkinsonism, sleep transition-related hallucinations, or moderate to severe depression to suggest a prodrome of an α-synucleinopathy, hypnopompic or hypnagogic hallucinations, or psychosis. Although based on only 1 Ojibwe Tribal Nation, this study suggests that formed visions of the nonphysical world are common among cognitively healthy Ojibwe individuals and can represent normal spiritual experiences. Clinicians would benefit from careful consideration of cultural or spiritual context to avoid misdiagnosis of neuropsychiatric disease.

REM Behavior Disorder: Implications for PD Therapeutics.

Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia that occurs during REM sleep, characterized by REM sleep without atonia (RSWA) and dream enactment behavior (DEB). RBD is associated with several diseases and medications but most notably is a prodromal feature of synucleinopathies, including Parkinson's disease (PD). This article reviews RBD, its treatments, and implications for PD therapeutics. Recent research recognizes RBD as a prodromal marker of PD, resulting in expansion of basic science and clinical investigations of RBD. Current basic science research investigates the pathophysiology of RBD and explores animal models to allow therapeutic development. Clinical research has focused on natural history observation, as well as potential RBD treatments and their impact on sleep and phenoconversion to neurodegenerative disease. RBD serves as a fresh access point to develop both neuroprotective and symptomatic therapies in PD. These types of investigations are novel and will benefit from the more established basic science infrastructure to develop new interventions.

REM Sleep Behavior Disorder and Its Possible Prodromes in General Population: Prevalence, Polysomnography Findings, and Associated Factors.

To evaluate the prevalence of REM sleep behavior disorder (RBD) and its possible prodromal conditions, isolated dream enactment behavior (DEB) and isolated REM without atonia (RWA), in a general population sample, and the factors associated with diagnosis and symptom frequency. From a population-based prospective cohort in Korea, 1,075 participants (age 60.1 ± 7.0 years; range 50-80 years; men 53.7%) completed the RBD screening questionnaire (RBDSQ), a structured telephone interview for the presence and characteristics of repeated DEB, and home polysomnography (PSG). RWA was measured on submentalis EMG, including 30-second epoch-based tonic and phasic activity as well as 3-second mini-epoch-based phasic and any EMG activities. Based on the presence of repeated DEB and any EMG activity of ≥22.3%, we categorized the participants into no RBD, isolated RWA, isolated DEB, and RBD groups. RBD was diagnosed in 20 participants, isolated RWA in 133 participants, and isolated DEB in 48 participants. Sex and DEB frequency-adjusted prevalence of RBD was 1.4% (95% CI 1.0%-1.8%), isolated RWA was 12.5% (95% CI 11.3%-13.6%), and isolated DEB was 3.4% (95% CI 2.7%-4.1%). Total RBDSQ score was higher in the RBD and isolated DEB groups than in the isolated RWA and no RBD group (median 5 [interquartile range (IQR) 4-6] for RBD, median 4 [IQR 3-6] for isolated DEB, median 2 [IQR 1-3] for isolated RWA, and median 2 [IQR 1-4] for no RBD groups, p < 0.001). RBDSQ score of ≥5 had good specificity but poor positive predictive value (PPV) for RBD (specificity 84.1% and PPV 7.7%) and its prodromal conditions (specificity 85.2% and PPV 29.1%). Among the RWA parameters, any EMG activity showed the best association with the RBD and its possible prodromes (area under the curve, 0.917). Three-second mini-epoch-based EMG activity and phasic EMG activity were correlated with the frequency of DEB (standardized Jonckheere-Terpstra statistic [std. J-T static] for trend = 0.488, p < 0.001, and std. J-T static = 3.265, p = 0.001, respectively). This study provides prevalence estimates of RBD and its possible prodromal conditions based on a structured telephone interview and RWA measurement on PSG from the general population.

Expert Opinion on Current Polysomnography Procedure for Diagnosis of Rapid Eye Movement Sleep Behavior Disorder in Korea

Rapid eye movement (REM) sleep behavior disorder (RBD) is diagnosed based on a history of dream-enactment behavior and documentation of REM sleep without atonia (RWA) on polysomnography (PSG). RWA can be quantified using various methods. To establish comprehensive and clear PSG criteria for diagnosing RBD, the International RBD Study Group (IRBDSG) has recently published guidelines, which include the use of a video-PSG technical setup, REM sleep staging, RWA scoring, video and audio recording and analyses, and a video-PSG procedure for the diagnosis and identification of the prodromal stages of neurodegenerative diseases. Although the guidelines can identify patients with homogeneous RBD, their applicability in a real-world setting, particularly in Korea, presents challenges. Therefore, the aim of the present study was to evaluate and introduce IRBDSG guidelines and results of Korean sleep experts’ opinion survey for diagnosing RBD based on PSG findings.

Parkinson's Disease Case Ascertainment in the Sister Study: A Cohort for Environmental Health Research.

Large prospective studies are essential for investigating the environmental causes of Parkinson's disease (PD), but diagnosis via clinical exams is often infeasible. To present case ascertainment strategy and data collection in a US cohort of women. In the Sister Study (n = 50,884, baseline ages 55.6±9.0), physician-made PD diagnoses were first reported by participants or their proxies. Cohort-wide follow-up surveys collected data on subsequent diagnoses, medication usage and PD-relevant motor and nonmotor symptoms. We contacted self-reported PD cases and their treating physicians to obtain relevant diagnostic and treatment history. Diagnostic adjudication was made via expert review of all available data, except nonmotor symptoms. We examined associations of nonmotor symptoms with incident PD, using multivariable logistic regression models and reported odds ratio (OR) and 95% confidence intervals (CI). Of the 371 potential PD cases identified, 242 diagnoses were confirmed. Compared with unconfirmed cases, confirmed cases were more likely to report PD diagnosis from multiple sources, medication usage, and motor and nonmotor feature consistently during the follow-up. PD polygenic risk score was associated with confirmed PD (ORinter-quartile range = 1.74, 95% CI: 1.45-2.10), but not with unconfirmed cases (corresponding OR = 1.05). Hyposmia, dream-enacting behaviors, constipation, depression, unexplained weight loss, dry eyes, dry mouth, and fatigue were significantly related to PD risk, with ORs from 1.71 to 4.88. Only one of the eight negative control symptoms was associated with incident PD. Findings support our PD case ascertainment approach in this large cohort of women. PD prodromal presentation is likely beyond its well-documented profile.

0657 Incidence and Features of Nightmares and Trauma Associated Sleep Disorder in U.S. Military Personnel with Sleep Disturbances

Abstract Introduction The incidence and clinical significance of nightmares is difficult to estimate due to varying criteria across studies. The Nightmare Disorder Index (NDI) is a validated measure to evaluate nightmare disorder. However, there is no measure to differentiate trauma-related nightmares compared to trauma associated sleep disorder (TSD), a unique REM parasomnia. The objectives of this study were to (1) determine the incidence of nightmare disorder and TSD in patients referred for a clinically indicated sleep evaluation, and (2) further characterize TSD. Methods All initial sleep referrals completed intake questionnaires including validated measures such as the NDI, Epworth Sleepiness Scale (ESS) and Insomnia Severity Index (ISI). Patients who endorsed at least weekly nightmares related to trauma, with vocalizations or disruptive nocturnal behaviors, and autonomic surges additionally received a structured clinical interview focusing on thematic content of dreams, dream enactment behavior, self-reported symptoms of autonomic hyperactivity, and, if previously treated, nightmare severity before and after therapy. Results 102 new patients completed the NDI and 56.9% (58) met criteria for probable nightmare disorder (ND). Of the 58 patients with probable ND, 13.8% (8) had symptoms consistent with TSD (7.8% of new referrals). Compared to ND patients, TSD patients were more likely to have higher ISI (24.0 ± 3.0 vs. 18.6 ± 5.6) (p=0.023) and total NDI score (15.8 ± 3.5 vs. 10.0 ± 3.7) (p&amp;lt; 0.001), but not ESS (p=0.158). Structured interview revealed all TSD patients had significant daytime distress or impairment. The nature of trauma was combat for 3 individuals, physical assault for 1, and sexual assault for 4 (one occurring while deployed). All individuals reported tachycardia secondary to nightmares and tachypnea and diaphoresis were each reported in 75% of patients. Regarding dream content, 25% endorsed accurate replay of trauma, 25% related to trauma but non-replay, and 50% mixed. For DNB, 87.5% of patients endorsed vocalization (moaning, screaming, or yelling), 87.5% endorsed movements (tossing, turning, or thrashing), and 37.5% endorsed combative behaviors (striking of bed partner). Conclusion This study reports a surprisingly high incidence of probable ND among all new sleep medicine patients. TSD appears to be a clinically distinct, more severe parasomnia compared to ND. Support (if any)