Sleep-onset rapid eye movement after electroconvulsive therapy is more frequent in patients who respond less well to electroconvulsive therapy

Alterations of neural network organisation during rapid eye movement sleep and slow-wave sleep in major depression: Implications for diagnosis, classification, and treatment

The aim of this study was to empirically investigate the network organisation during rapid eye movement sleep (REMS) and slow-wave sleep (SWS) using the effective connectivity measured using the Granger causality to identify new potential biomarkers for the diagnosis, classification, and potential favourable response to treatment in major depression. Polysomnographic data were analysed from 24 healthy individuals and 16 major depressed individuals recruited prospectively. To obtain the 19×19 connectivity matrix of all possible pairwise combinations of electrodes by the Granger causality method from our electroencephalographic data, we used the Toolbox MVGC multivariate Granger causality. The computation of network measures was realised by importing these connectivity matrices into the EEGNET Toolbox. Major depressed individuals (versus healthy individuals) and those with endogenous depression (versus those with neurotic depression) present alterations of small-world network organisation during REMS, whereas major depressed individuals with potential favourable response to electroconvulsive therapy (versus those with potential unfavourable response) have a less efficient small-world network organisation during SWS. Thus, alterations in network organisation during REMS could be biomarkers for the diagnosis and classification of major depressive episodes, whereas alterations of network organisation during SWS could be a biomarker to predict potential favourable response to treatment by electroconvulsive therapy.

Sleep at baseline and after electroconvulsive therapy in patients with major depression

Sleep in major depressive disorder is frequently altered and possibly indicative for treatment outcomes. For example, increased rapid eye movement (REM-) sleep density seems to predict worse treatment outcomes of psychotherapy. We therefore investigated pre-treatment sleep and sleep changes after termination of electroconvulsive therapy (ECT). Sleep was polysomnographically recorded. The analysed sample consisted of 15 inpatients with ages ranging from 30 to 80 (mean 59 years). ECT was applied two times a week up to 7 weeks. Stable remission of depressive symptoms was defined by a score in the Hamilton Rating Scale of Depression <8 at six months after ECT. The main results were an increase in sleep efficiency and a decrease in the number of awakenings within the course of ECT in the entire patient group. Significant increases in slow wave sleep and REM sleep duration and a significant decrease in REM density were only seen in stable remitters and not in non-remitters. In pre-treatment baseline sleep a higher REM density of the first REM sleep period was significantly associated with better ECT outcome. In conclusion, REM density of the first REM sleep period seems to be an interesting candidate as putative predictor of stable treatment outcome of ECT.

Short-term effects of electroconvulsive therapy on subjective and actigraphy-assessed sleep parameters in severely depressed inpatients

Background. Sleep disturbances are a key feature of major depression. Electroconvulsive treatment (ECT) may improve polysomnography-assessed sleep characteristics, but its short-term effects on actigraphy-assessed and subjective sleep characteristics are unknown. We therefore aimed to assess the effects of ECT on subjective and objective sleep parameters in a proof-of-principle study. Methods. We assessed subjective and objective sleep parameters in 12 severely depressed patients up to 5 consecutive days during their ECT course, corresponding to a total of 43 nights (including 19 ECT sessions). The 12 patients were 83% female and on average 62 (standard deviation (SD) 14) years old and had an average MADRS score of 40 at baseline (SD 21). Results. Subjective and objective sleep parameters were not directly affected by ECT. The subjective sleep efficiency parameter was similar on the day after ECT and other days. ECT did not affect the number of errors in the Sustained Attention to Response Task. Patients subjectively underestimated their total sleep time by 1.4 hours (P < 0.001) compared to actigraphy-assessed sleep duration. Conclusion. ECT did not affect subjective and actigraphy-assessed sleep in the short term. Depressed patients profoundly underestimated their sleep duration.

Electroconvulsive therapy improves antipsychotic and somnographic responses in adolescents with first-episode psychosis--a case-control study

OBJECTIVE

Previous studies have demonstrated the effectiveness of electroconvulsive therapy (ECT) in pharmacotherapy-resistant neuropsychiatric conditions. This study aimed to evaluate the efficacy and safety of ECT in adolescents with first-episode psychosis.

METHOD

This case-control study was conducted in inpatients aged 13-20 years with first-episode psychosis. Every three similar age and same gender patients consecutively recruited were randomly allocated to control and ECT group at a ratio of 1:2, while they had antipsychotic treatment. ECT treatment was performed for 3 sessions per week with a maximum of 14 sessions. The endpoint was discharge from hospital. Clinical outcomes were measured using hospital stay days, the Positive and Negative Syndrome Scale (PANSS) and response rate. Polysomnography (PSG) was conducted at baseline and at week 2. Safety and tolerability were also evaluated.

RESULTS

Between March 2004 and November 2009, 112 eligible patients were allocated to control (n=38) and ECT (n=74) group. Additional ECT treatment significantly reduced hospital stay compared to controls (23.2±8.2 days versus 27.3±9.3 days, mean±SD, P=0.018). Survival analysis revealed that the ECT-treated group had a significantly higher cumulative response rate than controls (74.3% versus 50%, relative risk (RR)=1.961, P=0.001). Additional ECT also produced significantly greater improvement in sleep efficiency, rapid eye movement (REM) latency and density than control condition. The PSG improvement significantly correlated with reduction in scores on overall PANSS, positive symptoms, and general psychopathology. No patients discontinued ECT treatment regimen during hospital stay. The incidence of most adverse events was not different in the two groups, but ECT-treated group had more complaints of transient headache and dizziness than controls.

CONCLUSIONS

ECT is an effective and safe intervention used in adolescents with first-episode psychosis. Its antipsychotic effects are associated with improved PSG variables. ECT can be considered as an early psychosis intervention.

Sleep Disturbances in Pediatric Depression

Depressive illness beginning early in life can have serious developmental and functional consequences. Therefore, understanding its etiology and pathophysiology during this developmental stage is critical for developing effective prevention and intervention strategies. There is considerable evidence of sleep alterations in adult major depressive disorder. However, studies in children and adolescents have not found consistent changes in sleep architecture paralleling adult depression. This review article summarizes sleep polysomnography research in early-onset depression, highlighting the factors associated with variable findings across studies. In addition, potential avenues for future research will be suggested in order to develop more comprehensive theoretical models and interventions for pediatric depression.

TASK-3 as a potential antidepressant target

Modulation of TASK-3 (Kcnk9) potassium channels affect neurotransmitter release in thalamocortical centers and other sleep-related nuclei having the capacity to regulate arousal cycles and REM sleep changes associated with mood disorders and antidepressant action. Circumstantial evidence from this and previous studies suggest the potential for TASK-3 to be a novel antidepressant therapeutic target; TASK-3 knock-out mice display augmented circadian amplitude and exhibit sleep architecture characterized by suppressed REM activity. Detailed analysis of locomotor activity indicates that the amplitudes of activity bout duration and bout number are augmented in TASK-3 mutants well beyond that seen in wildtypes, findings substantiated by amplitude increases in body temperature and EEG recordings of sleep stage bouts. Polysomnographic analysis of TASK-3 mutants reveals increases in nocturnal active wake and suppressed REM sleep time while increased slow wave sleep typifies the inactive phase, findings that have implications for the cognitive impact of reduced TASK-3 activity. In direct measures of their resistance to despair behavior, TASK-3 knock-outs displayed significant decreases in immobility relative to wildtype controls in both tail suspension and forced swim tests. Treatment of wildtype animals with the antidepressant Fluoxetine markedly reduced REM sleep, while leaving active wake and slow wave sleep relatively intact. Remarkably, these effects were absent in TASK-3 mutants indicating that TASK-3 is either directly involved in the mechanism of this drug's action, or participates in parallel pathways that achieve the same effect. Together, these results support the TASK-3 channel to act as a therapeutic target for antidepressant action.

Sleep and depression--results from psychobiological studies: an overview

Disturbances of sleep are typical for most depressed patients and belong to the core symptoms of the disorder. Polysomnographic sleep research has demonstrated that besides disturbances of sleep continuity, in depression sleep is characterized by a reduction of slow wave sleep and a disinhibition of REM sleep, with a shortening of REM latency, a prolongation of the first REM period and increased REM density. These findings have stimulated many sleep studies in depressive patients and patients with other psychiatric disorders. In the meantime, several theoretical models, originating from basic research, have been developed to explain sleep abnormalities of depression, like the two-process-model of sleep and sleep regulation, the GRF/CRF imbalance model and the reciprocal interaction model of non-REM and REM sleep regulation. Interestingly, most of the effective antidepressant agents suppress REM sleep. Furthermore, manipulations of the sleep-wake cycle, like sleep deprivation or a phase advance of the sleep period, alleviate depressive symptoms. These data indicate a strong bi-directional relationship between sleep, sleep alterations and depression.

Physiological effects of electroconvulsive therapy and transcranial magnetic stimulation in major depression

Major depressive episodes are associated with dysregulation of various physiologic systems. Antidepressant medications alter regulation of the hormonal and sleep systems. A thorough understanding of these changes may elucidate the pathophysiologic basis of the disorder [Amsterdam et al., 1989: Psychoneuroendocrinology 14:43-62], and interventions targeted directly at these systems are being increasingly recognized as possible treatments for depression [Wong et al., 2000: Proc Natl Acad Sci USA 97:325-330; Szuba et al., 1996: Proc Am Coll Neuropsychopharmacol Ann Meet]. These physiologic systems are regulated by the major neurotransmitters implicated in the etiology of mood disorders--norepinephrine, serotonin, and dopamine. Many of the hormones of import for this article also act as neurotransmitters and thus alter cerebral activity themselves [Owens and Nemeroff, 1993: Ciba Found Symp 172:296-308; Weitzner, 1998: Psychother Psychosom 67:125-132]. Parenteral infusion of hydrocortisone [DeBattista, 2000: Am J Psychiatry 157:1334-1337] and thyrotropin-releasing hormone (TRH) [Prange et al., 1972: Lancet 2:999-1002; Marangell et al., 1997: Arch Gen Psychiatry 54:214-222; Szuba, 1996: Proc Am Coll Neuropsychopharmacol Ann Meet.] produce acute antidepressant effects. Antagonists to corticotropin-releasing hormone and repeated parenteral infusion of TRH may have antidepressant activity when given during several weeks [Wong, 2000: Proc Natl Acad Sci USA 97:325-330; Arborelius et al., 1999: J Endocrinol 160:1-12; Callahan et al., 1997: Biol Psychiatry 41:264-272]. Manipulations of the sleep system through sleep deprivation can ameliorate depression [Szuba et al., 1994: Psychiatry Res 51:283-295; see Wirz-Justice et al., 1999: Biol Psychiatry 46:445-453 for review]. Sleep deprivation has been shown in more than three dozen studies published in the last three decades to produce marked, acute antidepressant effects in the majority of depressed individuals [Wirz-Justice, et al., 1999: Biol Psychiatry 46:445-453]. Thus, examination of the effects the two nonpharmacologic treatments, electroconvulsive therapy (ECT) and transcranial magnetic stimulation (TMS), produce in these physiologic systems may help elucidate their mechanisms of action, while enhancing understanding of the neurobiology of depressive illness. We will review these physiologic changes associated with depression, the effects that manipulations of these systems can have on depressive disorders, and then describe the effects the two techniques that can stimulate the human brain in vivo, ECT and TMS, exert on these systems.