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Biomedical subjects

C H Schenck

Publications and source records attributed to C H Schenck.

At least 37 records · Page 2Linked to original sources

An assessment of cognitive function and mood in chronic fatigue syndrome.

Data were gathered regarding the associates of chronic fatigue syndrome (CFS) with: (1) speed of cognitive processing, (2) motor speed, (3) ability to sustain attention, and (4) mood. Patients were given a brief neuropsychological test battery before and after double-blind treatment with terfenadine or placebo and completed a daily mood rating scale (Positive and Negative Affect Schedule) during the study. CFS patients exhibited slower cognitive processing and motor speed and lower positive affect, as compared to data reported from previous studies of healthy subjects and other patient groups; however, CFS patients did not exhibit deficits in sustained attention in comparison to other groups. The CFS patients' ability to attend to verbal versus figural stimuli and mood ratings were different from those reported in studies of patients with depression. Because of methodological limitations, these findings are preliminary, but they encourage further assessment of cognitive dysfunction and mood in CFS.

Adult↗

HLA class II genes associated with REM sleep behavior disorder.

Twenty-five white men with rapid eye movements (REM) sleep behavior disorder, but without narcolepsy, underwent HLA class II antigen typing: 84% (N=21) were DQwl (DQB1*05,06) positive (28% [N=7] were DR2 positive); DQB1*0501 (N=9) and DQB1*0602 (N=7) were the most common phenotypes. The 84% DQwl rate in men with REM sleep behavior disorder was significantly greater (p=0.015) than the 56% DQwl rate found in a local white comparison group (N=66), and was greater than the 39 to 66% DQwl rates published for 12 white groups (N=40-418/group). Thus, another disorder of REM sleep dysregulation (besides narcolepsy) appears to be strongly associated with specific HLA class II genes.

Electromyography↗

A case-control study to assess possible triggers and cofactors in chronic fatigue syndrome.

PURPOSE: To assess possible triggers and cofactors for chronic fatigue syndrome (CFS) and to compare levels of selected cytokines between cases and an appropriately matched control group. PATIENTS AND METHODS: We conducted a case-control study of 47 cases of CFS obtained through a regional CFS research program maintained at a tertiary care medical center. One age-, gender-, and neighborhood-matched control was identified for each case through systematic community telephone sampling. Standardized questionnaires were administered to cases and controls. Sera were assayed for transforming growth factor-beta (TGF-beta), interleukin-1 beta, interleukin-6, tumor necrosis factor-alpha, and antibody to Borrelia burgdorferi and Babesia microti. RESULTS: Cases were more likely to have exercised regularly before illness onset than controls (67% versus 40%; matched odds ratio (MOR) = 3.4; 95% CI = 1.2 to 11.8; P = 0.02). Female cases were more likely to be nulliparous prior to onset of CFS than controls (51% versus 31%; MOR = 8.0; 95% CI = 1.03 to 170; P = 0.05). History of other major factors, including silicone-gel breast implants (one female case and one female control), pre-morbid history of depression (15% of cases, 11% of controls) and history of allergies (66% of cases, 51% of controls) were similar for cases and controls. However, cases were more likely to have a diagnosis of depression subsequent to their diagnosis of CFS compared to a similar time frame for controls (MOR = undefined; 95% CI lower bound = 2.5; P < 0.001). Positive antibody titers to B burgdorferi (one case and one control) and B microti (zero cases and two controls) were also similar. CONCLUSIONS: Further investigation into the role of prior routine exercise as a cofactor for CFS is warranted. This study supports the concurrence of CFS and depression, although pre-morbid history of depression was similar for both groups.

Adolescent↗

Long-term, nightly benzodiazepine treatment of injurious parasomnias and other disorders of disrupted nocturnal sleep in 170 adults.

PURPOSE: To assess the efficacy, dose stability, safety, and abuse potential of long-term, nightly benzodiazepine treatment of chronic disorders of disrupted nocturnal sleep. PATIENTS AND METHODS: During a 12-year period, one author evaluated and treated 170 adult referrals for > or = 6 months with nightly benzodiazepine therapy for longstanding, sleep-disruptive disorders: injurious sleepwalking and sleep terrors (69); rapid eye movement sleep behavior disorder (52); chronic, severe insomnia (25); and restless legs syndrome/periodic limb movement disorder (24). RESULTS: Complete/substantial control of the sleep disorders was achieved by 146 patients (86%); 8% had adverse effects requiring medication changes; 2% had relapses of alcohol or chemical abuse requiring hospitalization; another 2% at times misused their medications. A total of 136 patients received clonazepam nightly for a mean 3.5 (+/- 2.4) years, with no significant difference in inital versus final mean dose: 0.77 mg (+/- 0.46) versus 1.10 mg (+/- 0.96). Similar results were obtained with chronic alprazolam treatment and with other benzodiazepine treatments. CONCLUSION: Long-term, nightly benzodiazepine treatment of injurious parasomnias and other disorders of disrupted nocturnal sleep resulted in sustained efficacy in most cases, with low risk of dosage tolerance, adverse effects, or abuse. Data from this study on the treatment of chronic, severe insomnia (a small subset of all insomnia) are not generalizable to the typical insomnia patient.

Adult↗

NREM sleep parasomnias.

The three states of mammalian being--wakefulness, REM sleep, and NREM sleep--are not mutually exclusive and may occur simultaneously, oscillate rapidly, or appear in dissociated or incomplete form to produce primary sleep parasomnias. Dysfunctions of a wide variety of organ systems may take advantage of the sleeping state to declare themselves, resulting in the secondary sleep parasomnias. Contrary to popular opinion, most of these often bizarre and frightening experiences are not the manifestation of underlying psychological or psychiatric conditions. Formal study in an experienced sleep disorders center usually reveals a diagnosable and treatable condition. Various parasomnias may result in injurious or violent behavior. The forensic science implications are beyond the scope of this article but have been reviewed extensively elsewhere. Continued study of unusual sleep-related events undoubtedly will reveal more fascinating conditions, expanding our knowledge of sleep physiology and strengthening the bonds between clinicians and basic science sleep researchers.

Bruxism↗

REM sleep parasomnias.

This article focuses primarily on REM sleep behavior disorder, a recently identified syndrome with a corresponding animal model. Diagnostic methods and criteria, treatment, and the world literature are reviewed, and the experience of the authors' institution--The Minnesota Regional Sleep Disorders Center (Minneapolis, MN)--is summarized. Other REM parasomnias, including nightmares, REM sleep-related sinus arrest, and sleep-related painful erections, are discussed briefly.

Animals↗

Delayed emergence of a parkinsonian disorder in 38% of 29 older men initially diagnosed with idiopathic rapid eye movement sleep behaviour disorder.

We report longitudinal data on a group of 29 male patients 50 years of age or older who were initially diagnosed as having idiopathic REM sleep behavior disorder (RBD) after extensive polysomnographic and neurologic evaluations. Thirty-eight percent (11/29) were eventually diagnosed as having a parkinsonian disorder (presumably Parkinson's disease) at a mean interval of 3.7 +/- 1.4 (SD) years after the diagnosis of RBD+, and at a mean interval of 12.7 +/- 7.3 years after the onset of RBD. To date, only 7% (2/29) of patients have developed any other neurologic disorder. At the time of RBD diagnosis, data from the RBD group with eventual Parkinson's disease (n = 11) and the current idiopathic RBD group (n = 16) were indistinguishable, with two exceptions: the RBD-Parkinson's disease group had a significantly elevated hourly index of periodic limb movements of non-REM sleep and an elevated REM sleep percentage. RBD was fully or substantially controlled with nightly clonazepam treatment in 89% (24/27) of patients in both groups. Thus, RBD can be the heralding manifestation of Parkinson's disease in a substantial subgroup of older male RBD patients. However, a number of presumed Parkinson's disease patients may eventually be diagnosed with multiple system atrophy (striatonigral degeneration subtype). Our findings indicate the importance of serial neurologic evaluations after RBD is diagnosed and implicate the pedunculopontine nucleus as a likely site of pathology in combined RBD-Parkinson's disease, based on experimental and theoretical considerations rather than on autopsy data.

Brain↗

A polysomnographically documented case of adult somnambulism with long-distance automobile driving and frequent nocturnal violence: parasomnia with continuing danger as a noninsane automatism?

A case of childhood-onset somnambulism is reported in which a 43-year-old man presented with repeated sleep-related injuries incurred during violent nocturnal activity, which included frenzied running, throwing punches and wielding knives. He had also driven an automobile a long distance during a presumed somnambulistic state. His wife had been repeatedly injured, and she felt that her life was threatened by his nocturnal violence 2-3 times yearly. Polysomnography (PSG) documented multiple episodes of complex and violent behaviors arising exclusively from stage 3/4 sleep, thus confirming the diagnosis of somnambulism. Other causes of sleep-related violence were excluded. The patient responded promptly to treatment with bedtime clonazepam, and benefit was maintained at 5-year follow-up. Although this strictly clinical case did not have any legal repercussions, it does carry forensic implications, particularly when placed in the context of the published medical literature on PSG-documented parasomnias (somnambulism, rapid eye movement sleep behavior disorder) containing explicit examples of recurrent violence, at times life-threatening, directed toward the bed partner and others. Thus, a new medical-legal concept is proposed, consisting of "parasomnia with continuing danger" as a noninsane automatism. Treatment guidelines, within the context of forensic medicine, are presented.

Adult↗

Two cases of premenstrual sleep terrors and injurious sleep-walking.

There are currently three recognized menstrual-related sleep disorders: premenstrual insomnia, menopausal insomnia and premenstrual hypersomnia. Another category, premenstrual parasomnia (sleep behavior disorder), is now suggested. Case 1, a 17-year-old female, presented with a 6-year history of exclusively premenstrual sleep terrors and injurious sleep-walking that began 1 year after menarche. During the four nights preceding each menses, she would scream and run from her bed. There was no history of premenstrual syndrome. Neurological evaluations had been unrevealing, apart from mild mental retardation and attention deficit disorder; there was no psychiatric history. Polysomnography 3 days before the onset of menses confirmed the diagnosis of sleep-walking. Pharmacotherapies were not satisfactory, but self-hypnosis at bedtime was rapidly effective with benefit sustained at 2.5-year follow-up. Case 2, a 46-year-old woman without psychiatric disorder, presented with a 5-year history of sleep terrors and injurious sleep-walking that initially was not menstrually related, but beginning 8 months prior to referral, she developed an exclusively premenstrual parasomnia that, after polysomnography, was partially controlled with bedtime self-hypnosis and clonazepam, 0.25 mg.

Adolescent↗

Review of nocturnal sleep-related eating disorders.

This review provides a historical background on sleep-related eating disorders, summarizes findings from a series of 38 adults, and presents a current classification. The "night-eating syndrome" was first reported in 1955; only nine reports on this syndrome appeared during the next 36 years, seven being single-case studies and two containing the objective monitoring of sleep, that is, polysomnography. In 1991 our sleep center reported on 19 cases, and in 1993 on 38 cases, diagnosed by polysomnography and clinical evaluations. Mean age was 39 years, mean duration of night-eating was 12 years, 66% were women, 68% had nightly binge eating, and 44% were overweight from night-eating. Sleepwalking was the predominant disorder responsible for night-eating; restless legs syndrome, obstructive sleep apnea, and various other conditions (including two cases of anorexia nervosa) were also identified. Cognitive-behavioral therapies were ineffective, but pharmacotherapy was very effective in controlling night-eating and inducing loss of excess weight, and often consisted of a dopaminergic agent taken with codeine at bedtime. Thus, sleep-related eating can be an occult but often treatable cause of obesity. Further research, utilizing polysomnography, is encouraged.

Adolescent↗

Effects of mild exercise on cytokines and cerebral blood flow in chronic fatigue syndrome patients.

Chronic fatigue syndrome (CFS) is an idiopathic disorder characterized by fatigue that is markedly exacerbated by physical exertion. In the present study, we tested the hypothesis that mild exercise (walking 1 mph [1 mile = 1.609 km] for 30 min) would provoke serum cytokine and cerebral blood flow abnormalities of potential pathogenic importance in CFS. Interleukin-1 beta, interleukin-6, and tumor necrosis factor alpha were nondetectable in sera of CFS patients (n = 10) and healthy control subjects (n = 10) pre- and postexercise. At rest, serum transforming growth factor beta (TGF-beta) levels were elevated in the CFS group compared with the control group (287 +/- 18 versus 115 +/- 5 pg/ml, respectively; P < 0.01). Serum TGF-beta and cerebral blood flow abnormalities, detected by single-photon emission-computed tomographic scanning, were accentuated postexercise in the CFS group. Although these findings were not significantly different from those in the control group, the effect of exercise on serum TGF-beta and cerebral blood flow appeared magnified in the CFS patients. Results of this study encourage future research on the interaction of physical exertion, serum cytokines, and cerebral blood flow in CFS that will adopt a more rigorous exercise program than the one used in this study.

Adult↗

Additional categories of sleep-related eating disorders and the current status of treatment.

Sleep-related eating disorders distinct from daytime eating disorders have recently been shown to be associated with sleepwalking (SW), periodic limb movement (PLM) disorder and triazolam abuse in a series of 19 adults. We now report eight other primary or combined etiologies identified by clinical evaluations and polysomnographic monitoring of 19 additional adults (mean age 40 years; 58% female): i) obstructive sleep apnea (OSA), with eating during apnea-induced confusional arousals (n = 3); ii) OSA-PLM disorder (n = 1); iii) familial SW and sleep-related eating (n = 2); iv) SW-PLM disorder (n = 1); v) SW-irregular sleep/wake pattern disorder (n = 1); vi) familial restless legs syndrome and sleep-related eating (n = 2); vii) anorexia nervosa with nocturnal bulimia (n = 2) and viii) amitriptyline treatment of migraines (n = 1). In our cumulative series of 38 patients (excluding six with simple obesity from daytime overeating), 44% were overweight (i.e. > 20% excess weight) from sleep-related eating. Nightly sleep-related binge eating (without hunger or purging) had occurred in 84% of patients. Onset of sleep-related eating was also closely linked with i) acute stress involving reality-based concerns about the safety of family members or about relationship problems (n = 6), ii) abstinence from alcohol and opiate/cocaine abuse (n = 2) and iii) cessation of cigarette smoking (n = 2). Current treatment data indicate a primary role of dopaminergic agents (carbidopa/L-dopa; bromocriptine), often combined with codeine and clonazepam, in controlling most cases involving SW and/or PLM disorder. Fluoxetine was effective in two of three patients. Nasal continuous positive airway pressure therapy controlled sleep-related eating in two OSA patients.

Adult↗

The role of a sleep disorder center in evaluating sleep violence.

To review the state-dependent nature of violence and present a clinically useful classification of sleep violence, this article reviews our experience with sleep-related violence, establishing a differential diagnosis, methods of evaluation, and treatment options. The study occurs in a full-service clinical sleep disorders center evaluating approximately 1000 patients annually with an active participation of 16 physicians representing seven specialties. The patients were self-, physician-, or court/social service-referred for evaluation of violent or injurious behaviors associated with the sleep period. Interventions were dependent on the final diagnosis following clinical and (usually) sleep laboratory evaluation. The main outcome measures were self-reported. During routine clinical evaluations at a multidisciplinary sleep disorder center, it has become apparent that violence is often state-dependent, occurring only during the sleep period, resulting from a number of both neurologic and psychiatric conditions (including malingering and Munchausen syndrome by proxy). In such cases, careful clinical and laboratory evaluation usually results in a specific diagnosis, with effective therapeutic recommendations. Violence may be state-dependent. It is clear that violent behaviors may arise from the sleep period, often without conscious awareness on the part of the subject. This has social, forensic, and clinical implications, and may help contribute to the understanding of violence in general.

Health Facilities↗

Motor dyscontrol in narcolepsy: rapid-eye-movement (REM) sleep without atonia and REM sleep behavior disorder.

Narcolepsy involves abnormalities of rapid-eye-movement (REM) sleep, including a short latency to the onset of REM sleep, hypnagogic hallucinations, and sleep paralysis. In addition, persistence of muscle tone by electromyographic criteria or excessive muscle twitching during REM sleep or both have been reported in treated and untreated narcoleptic patients. We report that another previously described abnormality of REM sleep, REM sleep behavior disorder, may also be a symptom of narcolepsy. This disorder was found in 10 narcoleptic patients during routine clinical evaluations involving polysomnography and multiple sleep latency tests. During REM sleep, 7 additional narcoleptic patients displayed persistent muscle tone and/or excessive twitching, which we believe to be subclinical components of REM sleep behavior disorder. These 17 patients, diagnosed by established criteria for narcolepsy and for REM sleep behavior disorder, ranged in age from 8 to 74 years. Seventy-one percent were male. Narcolepsy and REM sleep behavior disorder most commonly emerged in tandem. In 3 patients, treatment of narcolepsy-cataplexy with stimulants and tricyclics either induced or exacerbated REM sleep behavior disorder.

Adolescent↗

Prominent eye movements during NREM sleep and REM sleep behavior disorder associated with fluoxetine treatment of depression and obsessive-compulsive disorder.

The clinical polysomnographic (PSG) reports of 2,650 consecutive adults studied during 41 months were reviewed retrospectively to identify all patients treated with fluoxetine or tricyclic antidepressants. The PSG reports of four other adult groups were also reviewed: periodic limb movement (PLM) disorder (n = 28); sleep terror/sleepwalking (ST/SW) (n = 54); rapid eye movement (REM) sleep behavior disorder (RBD) (n = 70); patients with clinically unremarkable sleep during two consecutive PSG studies (n = 30). Standard PSG recording and scoring methods were employed. A total of 1.5% (n = 41) and 2.0% (n = 52) of patients were receiving fluoxetine or tricyclics (amitriptyline or nortriptyline, n = 31; imipramine or desipramine, n = 16; protriptyline or trimipramine, n = 5). A selective association between fluoxetine and extensive, prominent eye movements in nonrapid eye movement (NREM) sleep was detected, utilizing Fisher's exact one-tailed statistic (p less than 0.00001 for each comparison). The detection rates were fluoxetine, 48.8% (20/41); tricyclics, 5.8% (3/52); RBD, 4.3% (3/70); objectively normal sleepers, 3.3% (1/30); PLM, ST/SW, 0% (0/82). These groups had similar mean ages (31.5-45.4 years) and gender distributions (50.0-60.7% male), apart from RBD. The effect of fluoxetine, a potent and specific serotonin reuptake inhibitor, on NREM eye movements is postulated to derive from potentiation of serotonergic neurons that inhibit brainstem "omnipause neurons", which, in turn, inhibit saccadic eye movements, thus resulting in disinhibited release of saccades. In addition, a 31-year-old man with obsessive-compulsive disorder developed RBD soon after starting fluoxetine therapy, which persisted at PSG study 19 months after fluoxetine discontinuation.

Adult↗

Dissociated states of wakefulness and sleep.

Both sleep clinicians and basic science researchers have been witness to a wide variety of unusual clinical and experimental phenomena that represent admixtures, incomplete declaration, or rapid oscillations of the three states of being: wakefulness, rapid eye movement (REM) sleep, and nonrapid eye movement sleep. The concept of state dissociation provides an explanation for a wide variety of bizarre clinical phenomena, including the symptoms of narcolepsy, REM sleep behavior disorder, disorders of arousal (such as sleep terrors, sleepwalking, and sleep drunkenness), automatic behavior, and some "out-of-body" experiences. The purpose of this review is to provide an overview and perspective of such conditions, encourage systematic and detailed study of these "experiments in nature," and underscore the interdependence of clinicians and researchers.

Adolescent↗