Showing papers by "Michael H. Silber published in 2014"

Diagnostic Thresholds for Quantitative REM Sleep Phasic Burst Duration, Phasic and Tonic Muscle Activity, and REM Atonia Index in REM Sleep Behavior Disorder with and without Comorbid Obstructive Sleep Apnea

Abstract: OBJECTIVES We aimed to determine whether phasic burst duration and conventional REM sleep without atonia (RSWA) methods could accurately diagnose REM sleep behavior disorder (RBD) patients with comorbid OSA. DESIGN We visually analyzed RSWA phasic burst durations, phasic, "any," and tonic muscle activity by 3-s mini-epochs, phasic activity by 30-s (AASM rules) epochs, and conducted automated REM atonia index (RAI) analysis. Group RSWA metrics were analyzed and regression models fit, with receiver operating characteristic (ROC) curves determining the best diagnostic cutoff thresholds for RBD. Both split-night and full-night polysomnographic studies were analyzed. SETTING N/A. PARTICIPANTS Parkinson disease (PD)-RBD (n = 20) and matched controls with (n = 20) and without (n = 20) OSA. INTERVENTIONS N/A. MEASUREMENTS AND RESULTS All mean RSWA phasic burst durations and muscle activities were higher in PD-RBD patients than controls (P < 0.0001), and RSWA associations with PD-RBD remained significant when adjusting for age, gender, and REM AHI (P < 0.0001). RSWA muscle activity (phasic, "any") cutoffs for 3-s mini-epoch scorings were submentalis (SM) (15.5%, 21.6%), anterior tibialis (AT) (30.2%, 30.2%), and combined SM/AT (37.9%, 43.4%). Diagnostic cutoffs for 30-s epochs (AASM criteria) were SM 2.8%, AT 11.3%, and combined SM/AT 34.7%. Tonic muscle activity cutoff of 1.2% was 100% sensitive and specific, while RAI (SM) cutoff was 0.88. Phasic muscle burst duration cutoffs were: SM (0.65) and AT (0.79) seconds. Combining phasic burst durations with RSWA muscle activity improved sensitivity and specificity of RBD diagnosis. CONCLUSIONS This study provides evidence for REM sleep without atonia diagnostic thresholds applicable in Parkinson disease-REM sleep behavior disorder (PD-RBD) patient populations with comorbid OSA that may be useful toward distinguishing PD-RBD in typical outpatient populations.

Impulse control disorders in patients with dopamine agonist-treated prolactinomas and nonfunctioning pituitary adenomas: a case-control study.

Abstract: Objective We aimed to assess the prevalence of impulse control disorders (ICDs) in patients with prolactin-secreting adenomas treated with dopamine agonists (DAs), to identify associated factors, and compare it with a group of patients with non-functioning pituitary adenoma.

Abnormal daytime sleepiness in dementia with Lewy bodies compared to Alzheimer’s disease using the Multiple Sleep Latency Test

Abstract: Excessive daytime sleepiness is a commonly reported problem in dementia with Lewy bodies (DLB). We examined the relationship between nighttime sleep continuity and the propensity to fall asleep during the day in clinically probable DLB compared to Alzheimer’s disease (AD) dementia. A full-night polysomnography was carried out in 61 participants with DLB and 26 with AD dementia. Among this group, 32 participants with DLB and 18 with AD dementia underwent a daytime Multiple Sleep Latency Test (MSLT). Neuropathologic examinations of 20 participants with DLB were carried out. Although nighttime sleep efficiency did not differentiate diagnostic groups, the mean MSLT initial sleep latency was significantly shorter in participants with DLB than in those with AD dementia (mean 6.4 ± 5 minutes vs 11 ± 5 minutes, P <0.01). In the DLB group, 81% fell asleep within 10 minutes compared to 39% of the AD dementia group (P <0.01), and 56% in the DLB group fell asleep within 5 minutes compared to 17% in the AD dementia group (P <0.01). Daytime sleepiness in AD dementia was associated with greater dementia severity, but mean MSLT latency in DLB was not related to dementia severity, sleep efficiency the night before, or to visual hallucinations, fluctuations, parkinsonism or rapid eye movement sleep behavior disorder. These data suggest that abnormal daytime sleepiness is a unique feature of DLB that does not depend on nighttime sleep fragmentation or the presence of the four cardinal DLB features. Of the 20 DLB participants who underwent autopsy, those with transitional Lewy body disease (brainstem and limbic) did not differ from those with added cortical pathology (diffuse Lewy body disease) in dementia severity, DLB core features or sleep variables. Daytime sleepiness is more likely to occur in persons with DLB than in those with AD dementia. Daytime sleepiness in DLB may be attributed to disrupted brainstem and limbic sleep–wake physiology, and further work is needed to better understand the underlying mechanisms.

Lesional REM sleep behavior disorder localizes to the dorsomedial pons.

Abstract: REM sleep behavior disorder (RBD) is characterized by dream enactment behaviors (DEB) and REM sleep without atonia (RSWA). A key structure in REM sleep muscle tone regulation in the rodent model is the sublateral dorsal (SLD) tegmental nucleus in the dorsomedial pons.1 Lesions of an analogous structure, the subceruleus (SC) nucleus are thought to mediate RSWA in humans, enabling DEB.1,2 However, in vivo human studies of discrete dorsomedial pontine lesions causing RBD in isolation have been limited.2–4 We report such a case of lesional RBD due to vasculitis. The Mayo Clinic Institutional Review Board approved this study. Acknowledgment: The authors thank Lori Lynn Reinstrom, Department of Neurology, Mayo Clinic, for assistance with copyediting and manuscript submission.

Greatest rapid eye movement sleep atonia loss in men and older age.

Abstract: To determine quantitative REM sleep muscle tone in men and women without REM sleep behavior disorder, we quantitatively analyzed REM sleep phasic and tonic muscle activity, phasic muscle burst duration, and automated REM atonia index in submentalis and anterior tibialis muscles in 25 men and 25 women without REM sleep behavior disorder. Men showed significantly higher anterior tibialis phasic muscle activity. Higher phasic muscle activity was independently associated with male sex and older age in multivariate analysis. Men and the elderly may be biologically predisposed to altered REM sleep muscle atonia control, and/or some may have occult neurodegenerative disease, possibly underlying the predominance of older men with REM sleep behavior disorder.

Chiari 1 Malformation Presenting as Central Sleep Apnea during Pregnancy: A Case Report, Treatment Considerations, and Review of the Literature

Abstract: Purpose: Chiari malformation (CM) type 1 frequently causes obstructive or central sleep-disordered breathing (SDB) in both adults and children, although SDB is relatively rare as a presenting manifestation in the absence of other neurological symptoms. The definitive treatment of symptomatic CM is surgical decompression. We report a case that is, to our knowledge, a novel manifestation of central sleep apnea (CSA) due to CM type 1 with severe exacerbation and initial clinical presentation during pregnancy. Methods: Case report from tertiary care comprehensive sleep medicine center with literature review of sleep-disordered breathing manifestations associated with CM type 1. PubMed search was conducted between January 1982 and October 2013. Results: We report a 25-year-old woman with severe central sleep apnea initially presenting during her first pregnancy that eventually proved to be caused by CM type 1. The patient was successfully treated preoperatively by adaptive servoventilation (ASV), with effective resolution of sleep-disordered breathing following surgical decompression, and without recurrence in a subsequent pregnancy. Our literature review found that 58% of CM patients with SDB had OSA alone, 28% had CSA alone, 8 (10%) had mixed OSA/CSA, and 6 (8%) had hypoventilation. Of CM patients presenting with SDB, 50% had OSA, 42% had CSA, 8% had mixed OSA/CSA, and 10.4% had hypoventilation. We speculate that CSA may develop in CM patients in whom brainstem compression results in excessive central chemoreflex sensitivity with consequent hypocapnic CSA. Conclusions: CM type 1 may present with a diversity of SDB manifestations, and timely recognition and surgical referral are necessary to prevent further neurological deficits. ASV therapy can effectively manage CSA caused by CM type 1, which may initially present during pregnancy.

Restless Legs Syndrome (RLS)

Abstract: Restless legs syndrome (RLS) (Willis–Ekbom disease) is characterized by an urge to move while at rest relieved by movement and worse in the evening and at night. The prevalence of clinically significant RLS is 1.5–2.7%. RLS has a genetic basis with linkages noted to several chromosomal sites and associations described with a number of genes. Iron deficiency in the basal ganglia and low dopamine may play a role in pathogenesis. Dopamine agonists are the most commonly used drugs for treatment, but may result in augmentation, hypersomnia, and impulse control disorders. Alternative therapies include calcium channel ligands, opioids, and benzodiazepines.

Diagnostic Thresholds for Quantitative REM Sleep Muscle Densities, Phasic Burst Duration, and REM Atonia Index in REM Sleep Behavior Disorder with Co-morbid Obstructive Sleep Apnea (P5.283)

Abstract: Introduction Previous REM sleep without atonia (RSWA) studies have excluded patients with sleep apnea, potentially limiting application to clinical REM sleep behavior disorder (RBD) populations. We determined whether phasic burst duration and conventional RSWA methods could accurately diagnose RBD patients with co-morbid OSA. Materials and methods We analyzed RSWA phasic burst durations, phasic, “any” and tonic densities, and automated REM atonia index (RAI) in RBD and matched controls with OSA. Group RSWA metrics were then analyzed and regression models fit to explore associations with clinical variables, with receiver operator characteristic (ROC) curves determining the best diagnostic cut-off thresholds for RBD diagnosis. Results All mean RSWA phasic durations and densities were higher in RBD patients than controls ( p p Conclusion This study provides evidence for RSWA diagnostic thresholds applicable in clinical RBD patient populations with co-morbid OSA using conventional EMG lead placements during split-night polysomnograms, with suggested cut-offs for combined SM/AT muscles of 43.4%, RAI of 0.88, and phasic muscle burst durations of 0.65 and 0.79 s in the SM and AT muscles, respectively. Future studies with similar methods in idiopathic RBD patients with co-morbid OSA are planned. Acknowledgements The project described was supported by a Mayo Clinic Alzheimer’s Disease Research Center Grant Award from the National Institute on Aging (P50 AG016574), and the National Center for Research Resources and the National Center for Advancing Translational Sciences, National Institutes of Health, through Grant No. 1 UL1 RR024150-01. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH.