Sleep onset REM periods in schizophrenic patients

Troubles psychotiques et troubles du sommeil : revue de la littérature

Contexte La disparition de la nomenclature des troubles du sommeil dits primaires ou secondaires, rendue obsolète par le Manuel diagnostique et statistique des troubles mentaux (DSM-5), représente bien l’engouement académique actuel pour ce domaine de recherche. Il est de plus en plus reconnu que les troubles du sommeil sont plus que de simples conséquences d’un trouble psychiatrique et qu’ils peuvent persister malgré un traitement adéquat de la condition comorbide et même précéder ou exacerber cette dernière. Les troubles du sommeil dans les troubles psychotiques, très fréquents, sont donc devenus un sujet d’actualité, représentant une cible d’intervention jusqu’ici sous-estimée.

Objectif Cet article vise à présenter l’état des connaissances actuelles sur la relation entre les troubles du sommeil et les troubles psychotiques ainsi que sur l’utilisation de la thérapie cognitivo-comportementale (TCC) pour traiter les troubles du sommeil dans ce contexte.

Méthode L’article fait une recension narrative de la littérature pour décrire la relation bidirectionnelle entre la psychose et les troubles du sommeil, les corrélations cliniques et les traitements ciblant l’insomnie chez les patients psychotiques.

Résultats Malgré la présence d’une relation entre les troubles du sommeil et les troubles psychotiques, les mécanismes neuronaux, hormonaux et socioculturels régissant cette relation demeurent encore incertains. Bien que l’association reliant les troubles du sommeil et les troubles psychotiques demeure à clarifier, les études démontrent qu’elle serait bidirectionnelle et peut engendrer un cercle vicieux où ces deux composantes s’aggravent mutuellement. Dans ce contexte de comorbidités, les modèles unifiés en TCC deviennent un traitement de choix, à condition d’adapter les protocoles de TCC pour insomnie (TCC-i) à une population avec trouble psychotique (TCC-ip).

Conclusion Malgré la complexité de la relation entre les troubles psychotiques et ceux du sommeil, la TCC-i a été démontrée efficace pour traiter les troubles du sommeil dans une population psychotique et pourrait, dans certains cas, permettre d’alléger la symptomatologie psychotique. De futures études sur ce domaine pourraient permettre le développement de protocoles de thérapie cognitivo-comportementale pour les troubles du sommeil mieux adaptés à la population avec troubles psychotiques.

Narcolepsy and emotional experience: a review of the literature

Narcolepsy is a chronic sleep disorder characterized by excessive daytime sleepiness, cataplexy, hypnagogic hallucinations, and sleep paralysis. This disease affects significantly the overall patient functioning, interfering with social, work, and affective life. Some symptoms of narcolepsy depend on emotional stimuli; for instance, cataplectic attacks can be triggered by emotional inputs such as laughing, joking, a pleasant surprise, and also anger. Neurophysiological and neurochemical findings suggest the involvement of emotional brain circuits in the physiopathology of cataplexy, which seems to depending on the dysfunctional interplay between the hypothalamus and the amygdala associated with an alteration of hypocretin levels. Furthermore, behavioral studies suggest an impairment of emotions processing in narcolepsy-cataplexy (NC), like a probable coping strategy to avoid or reduce the frequency of cataplexy attacks. Consistently, NC patients seem to use coping strategies even during their sleep, avoiding unpleasant mental sleep activity through lucid dreaming. Interestingly, NC patients, even during sleep, have a different emotional experience than healthy subjects, with more vivid, bizarre, and frightening dreams. Notwithstanding this evidence, the relationship between emotion and narcolepsy is poorly investigated. This review aims to provide a synthesis of behavioral, neurophysiological, and neurochemical evidence to discuss the complex relationship between NC and emotional experience and to direct future research.

Narcolepsy and Psychiatric Disorders: Comorbidities or Shared Pathophysiology?

Narcolepsy and psychiatric disorders have a significant but unrecognized relationship, which is an area of evolving interest, but unfortunately, the association is poorly understood. It is not uncommon for the two to occur co-morbidly. However, narcolepsy is frequently misdiagnosed initially as a psychiatric condition, contributing to the protracted time to accurate diagnosis and treatment. Narcolepsy is a disabling neurodegenerative condition that carries a high risk for development of social and occupational dysfunction. Deterioration in function may lead to the secondary development of psychiatric symptoms. Inversely, the development of psychiatric symptoms can lead to the deterioration in function and quality of life. The overlap in pharmaceutical intervention may further enhance the difficulty to distinguish between diagnoses. Comprehensive care for patients with narcolepsy should include surveillance for psychiatric illness and appropriate treatment when necessary. Further research is necessary to better understand the underlying pathophysiology between psychiatric disease and narcolepsy.

The role of sleep dysfunction in the occurrence of delusions and hallucinations: A systematic review

BACKGROUND

Sleep dysfunction is extremely common in patients with schizophrenia. Recent research indicates that sleep dysfunction may contribute to psychotic experiences such as delusions and hallucinations.

OBJECTIVES

The review aims to evaluate the evidence for a relationship between sleep dysfunction and individual psychotic experiences, make links between the theoretical understanding of each, and highlight areas for future research.

METHOD

A systematic search was conducted to identify studies investigating sleep and psychotic experiences across clinical and non-clinical populations.

RESULTS

66 papers were identified. This literature robustly supports the co-occurrence of sleep dysfunction and psychotic experiences, particularly insomnia with paranoia. Sleep dysfunction predicting subsequent psychotic experiences receives support from epidemiological surveys, research on the transition to psychosis, and relapse studies. There is also evidence that reducing sleep elicits psychotic experiences in non-clinical individuals, and that improving sleep in individuals with psychosis may lessen psychotic experiences. Anxiety and depression consistently arise as (partial) mediators of the sleep and psychosis relationship.

CONCLUSION

Studies are needed that: determine the types of sleep dysfunction linked to individual psychotic experiences; establish a causal connection between sleep and psychotic experiences; and assess treatments for sleep dysfunction in patients with non-affective psychotic disorders such as schizophrenia.

Insomnia comorbid to severe psychiatric illness

In psychiatric illness, there is a growing body of evidence indicating that sleep disturbances exert a detrimental influence on the course of these disorders and contribute to impaired function. Even when psychiatric disorders are successfully treated or stabilized, insomnia and other sleep disturbances often fail to remit. The present review focuses on sleep in two severe mental illnesses, namely bipolar disorder and schizophrenia. This article discusses the role of sleep disturbances and altered sleep architecture in relation to symptom status, functional impairment, quality of life, and the course of these disorders. Current evidence regarding pharmacological and psychological treatment approaches for insomnia in these populations is presented. This review also notes considerations for adapting Cognitive Behavioral Therapy for insomnia (CBT-I) procedures for severe mental illness and proposes directions for future research.

Psychiatric disorders and sleep

There is growing experimental evidence that the relationship between psychiatric disorders and sleep is complex and includes bidirectional causation. This article provides the evidence that supports this point of view, reviewing data on sleep disturbances seen in patients with psychiatric disorders as well as data on the impact of sleep disturbances on psychiatric conditions. Although much has been learned about the psychiatric disorders-sleep relationship, additional research is needed to better understand the relationship. Such work promises to improve comprehension of these phenomena and lead to better treatment for the many patients with sleep disorders and psychiatric disorders.

Effects of antipsychotic medications on sleep in schizophrenia

Schizophrenia is often accompanied by sleep problems. Evidence exists that these sleep difficulties have significant effects on individuals with this disorder. The mainstay of treatment for this condition is the administration of medications that have effects on neurotransmitter systems, which play an important role in sleep-wake function, including histamine, acetylcholine, serotonin, norepinephrine and dopamine. Little systematic attention, however, has been paid to how the sleep effects of these agents might play a role in the course of treatment, function and quality of life of schizophrenia patients. Schizophrenia medications can improve sleep problems and reverse the sleep architectural derangements that are common among patients with schizophrenia and, therefore, have the potential to improve the quality of life and functional capacity of the patient. Conversely, some sleep-wake effects of these medications can impair patient function and quality of life. In this study, we review the effects of schizophrenia medications and discuss their relevance to optimizing the clinical treatment of people with schizophrenia with regard to sleep-wake function.

Sleep onset REM periods in obsessive compulsive disorder

Sleep studies in patients with obsessive compulsive disorder (OCD) are sparse and results inconsistent. Moreover, in 3 out of 4 published studies up to 50% of patients suffered from secondary major depression. In this study, 10 inpatients with a DSM-IV diagnosis of OCD without comorbid major depression (Yale-Brown Obsessive Compulsive Scale (Y-BOCS) score >15; Hamilton Depression Rating Scale (HAMD)-21 total score <17) and 10 healthy matched controls were included. Polysomnography of patients (7 males, 3 females, 34.5+/-12.7 years, Y-BOCS: 27.8+/-4.6, HAMD-21: 13.3+/-1.9) and controls (7 males, 3 females, 34.4+/-12.8 years) was recorded, following an adaptation night. Sleep variables did not significantly differ in both groups except that stage 4 sleep was reduced in patients. Three of the patients with OCD, however, exhibited sleep onset REM periods (SOREMPs), i.e. rapid-eye-movement (REM) latencies <10 min. Obsessive compulsive symptoms were significantly (P<0.05) more severe in these patients (Y-BOCS: 32+/-2.0) compared to those without SOREMPs (Y-BOCS 26+/-4.2). This is, to our knowledge, the first report of sleep onset REM periods in OCD.

Sleep in schizophrenia: impairments, correlates, and treatment

In untreated schizophrenia, psychotic decompensation is associated with profound insomnia, one of the prodromal symptoms associated with psychotic relapse. First- and second-generation antipsychotic medication can ameliorate this insomnia, but side effects may include sedation or residual insomnia. Patients who are clinically stable and medicated may continue to experience disturbed sleep, including long sleep-onset latencies, poor sleep efficiency, slow wave sleep deficits, and short rapid eye movement latencies. Schizophrenia also can be associated with comorbid sleep disorders, which may be enhanced or induced by antipsychotic medication. Sleep disorders in schizophrenia should be treated vigorously because normalized sleep and its restorative processes may be essential for a positive clinical outcome.

Clinical significance of sleep EEG abnormalities in chronic schizophrenia

This study aimed to investigate the relationship between measures of clinical symptom severity and sleep EEG parameters in a relatively diagnostically homogeneous group of patients with schizophrenia. We obtained sleep EEG data in 15 drug-free inpatients who met DSM-IV-R criteria for schizophrenia, undifferentiated type, with 15 age- and sex-matched normal controls over two consecutive night polysomnographic recordings. Clinical symptoms were assessed by the Positive and Negative Symptom Scale (PANSS) and Hamilton Rating Scale for Depression. Characteristic features of sleep disturbance were seen in patients with schizophrenia: profound difficulties in sleep initiation and maintenance, poor sleep efficiency, a slow wave sleep (SWS) deficit, and an increased REM density. SWS was inversely correlated with cognitive symptoms. REM density was inversely correlated with positive, cognitive, and emotional discomfort symptoms as well as PANSS total score. Our data demonstrate that drug-free patients with chronic undifferentiated type schizophrenia suffer from profound disturbances in sleep continuity and sleep architecture. Both the SWS deficit and cognitive impairment found in schizophrenics in this study may relate to similar underlying structural brain abnormalities.

Sleep quality in schizophrenia and the effects of atypical antipsychotic medication

BACKGROUND

Sleep disorders are widespread among patients with schizophrenia and contribute to adverse clinical outcomes. Antipsychotic drugs exert varying effects on sleep, and the effects of atypical agents may differ from those of conventional neuroleptics.

OBJECTIVE

To review the literature on the effects of atypical medication on subjective and objective sleep quality in patients with schizophrenia.

METHODS

A non-systematic literature review of Medline was performed in August 2003 searching the period from January 1985 to August 2003 for studies of the effects of atypical antipsychotics on sleep.

RESULTS

We found published studies of clozapine, olanzapine, and risperidone, but none on quetiapine or ziprasidone. Studies with clozapine showed that it increased total sleep time, sleep efficiency, stage-2 non-rapid eye movement sleep and rapid eye movement (REM) sleep density, and decreased stage-4 sleep, slow wave sleep (SWS) and stage-1 sleep. Single-dose studies with olanzapine have shown that it increases SWS, sleep continuity, total sleeping time, subjective sleep quality, and delta sleep. Long-term studies with risperidone have shown improvements in total sleep, sleep efficiency, sleep continuity, SWS, and stage-2 sleep, and reductions in sleep latency, number of awakenings, and proportion of time awake. These benefits were paralleled by improvements in subjective sleep assessment and psychopathology, and psychosocial functioning.

CONCLUSIONS

The evidence presented in this review suggests that atypical antipsychotics exert favorable effects on sleep profile compared with conventional agents, including improvement of subjective sleep quality and modification of specific sleep stages known to be associated with better clinical outcome.

Sleep in schizophrenia patients and the effects of antipsychotic drugs

Insomnia is a common feature in schizophrenia. However, it seldom is the predominant complaint. Nevertheless, severe insomnia is often seen during exacerbations of schizophrenia, and may actually precede the appearance of other symptoms of relapse. The sleep disturbances of either never-medicated or previously treated schizophrenia patients are characterized by a sleep-onset and maintenance insomnia. In addition, stage 4 sleep, slow wave sleep (stages 3 and 4), non-REM (NREM) sleep in minutes and REM latency are decreased. The atypical antipsychotics olanzapine, risperidone, and clozapine significantly increase total sleep time and stage 2 sleep. Moreover, olanzapine and risperidone enhance slow wave sleep. On the other hand, the typical antipsychotics haloperidol, thiothixene, and flupentixol significantly reduce stage 2 sleep latency and increase sleep efficiency. Future research should address: (1) the sleep patterns in subtypes of schizophrenia patients; (2) the role of neurotransmitters other than dopamine in the disruption of sleep in schizophrenia; (3) the functional alterations in CNS areas related to the pathophysiology of schizophrenia during NREM sleep and REM sleep (brain imaging studies); (4) the short-term, intermediate-term, and long-term effects of atypical antisychotics on sleep variables.

Elicitation of sleep-onset REM periods in normal individuals using the sleep interruption technique (SIT)

Use of the sleep interruption technique (SIT) to elicit sleep onset REM periods (SOREMPs) in normal individuals is introduced along with its theoretical bases, empirical findings, and potential applications. Capitalizing upon the circadian and ultradian nature of REM sleep, the SIT has been developed to examine various psychophysiological characteristics related to REM sleep. The SIT allows us to: (1) obtain SOREMPs at the discretion of the researcher; (2) avoid the contaminating effects of preceding non-REM (NREM)-REM stage ordering on subsequent target sleep episodes; and (3) obtain many REM episodes in a short time by repeating the sleep interruptions. The SIT has been applied in several studies, such as examination of physiological precursors to REM periods, correlates of dream mechanisms, and induction of sleep paralysis in normal individuals. Guidelines for eliciting SOREMP using the SIT, including the parameters to be manipulated, are provided, e.g. NREM duration before sleep interruption, time of night of awakenings, duration of sleep interruption and tasks employed. Directions for further research such as determining optimal type of task to promote SOREMP occurrences, generalization of SOREMP as usual REM periods, and forms of SOREMP occurrences under different conditions in normal individuals and clinical patients are discussed. Finally, possible future uses of the SIT, including combining this technique with new technologies, are also suggested.

Sleep-onset rapid eye movement periods in neuropsychiatric disorders: implications for the pathophysiology of psychosis

This paper reviews the literature describing the occurrence of sleep-onset rapid eye movement periods in narcolepsy, schizophrenia, psychotic depression, and delirium tremens; the association of narcolepsy with psychotic disorders; the neuropathology of the brainstem in narcolepsy and schizophrenia; and other behavioral disorders resulting from probable brainstem pathology. These findings suggest that some forms of psychosis are a manifestation of pathophysiological changes in the brainstem. Some implications of this hypothesis for the treatment of psychoses are discussed. Future research should investigate psychoses and the psychobiological correlates of such biological markers as sleep-onset rapid eye movement periods across diagnostic categories.

Biological predictors of 1-year outcome in schizophrenia in males and females

This paper describes a prospective study designed to ascertain the predictive value of biological factors associated with schizophrenia in males and females. In a sample of 59 medication-free schizophrenic inpatients (41 males; 18 females), we assessed the correlation of four factors--rapid eye movement (REM) sleep latency, delta (slow-wave) sleep, dexamethasone suppression test (DST) cortisol levels, and ventricle-brain ratio (VBR)--with several dimensions of outcome at 1-year post-discharge. In the total sample, shorter REM latency was associated with poor outcome on all dimensions measured: rehospitalization, employment, social activity, symptomatology, and global functioning. However, none of the other biological factors were associated with any measure of outcome. The predictive value of REM latency appeared to be gender-specific; in general, the relationships between reduced REM latency and poor outcome were consistently noted in females, but were not significant in males. These results suggest that a common, possibly gender-related, pathophysiological mechanism might underlie both abnormal REM latency and poor outcome. The findings underscore the importance of considering gender differences in studies of schizophrenia.

Effects of zopiclone on sleep and symptoms in schizophrenia: comparison with benzodiazepine hypnotics

Sleep variables and psychiatric symptoms were investigated in 6 male chronic schizophrenic outpatients. The patients were being treated with benzodiazepine (BZD) hypnotics for more than 8 weeks, and BZDs were replaced with zopiclone (ZPC) 15 mg/day. Polysomnographic examinations, subjective sleep assessments and BPRS scoring were performed during BZD therapy and at the end of 8 weeks of ZPC therapy. The doses of neuroleptics and anticholinergic agents remained fixed throughout the study. The amount of slow-wave sleep (SWS) was markedly small and that of stage 1 sleep was moderately large during BZD therapy. The amount of stage 1 was smaller and that of stage 2 was larger during treatment with ZPC than BZDs. There were no significant change in the amount of SWS between the treatment. Half of the patients exhibited a sleep-onset REM period (SOREMP) during ZPC therapy. Both total BPRS score and negative symptom score were lower during treatment with ZPC than BZDs. These results suggest that ZPC may be more beneficial in treating schizophrenic insomnia than BZD hypnotics and that reduced SWS and SOREMP may be partly involved in the pathophysiology of schizophrenia.