H. Lôo

Maintenance electroconvulsive therapy: an alternative treatment for refractory schizophrenia and schizoaffective disorders.

This retrospective chart review of a clinical cohort of 19 refractory schizophrenic or schizoaffective patients treated with maintenance electroconvulsive therapy addresses the indications for this treatment, its efficacy, and its impact on daily functioning and hospitalizations. Maintenance electroconvulsive therapy combined with medication appears to be an efficient alternative to pharmacological treatment alone.

Variable individual sensitivity to cannabis in patients with schizophrenia

There is now compelling evidence that cannabis consumption might precipitate psychosis onset. The objective of the present study was to assess the role of individual sensitivity to the psychotogenic effect of cannabis in male patients with schizophrenia. The lifetime diagnosis, disease and substance-use history were determined using a standardized interview in 190 patients with schizophrenia. Of patients with lifetime cannabis use (n=121), 44 were characterized as Cannabis-sensitive (CS) patients if the onset of psychotic symptoms occurred within 1 month following the initiation of cannabis consumption, or following a marked rise of cannabis consumption, or marked aggravation of psychotic symptoms each time the subject used cannabis. Age at onset of psychosis was not different in patients with lifetime cannabis use compared to non-users. By contrast, the first psychotic episode occurred 2.6 yr earlier in CS compared to Non-cannabis-sensitive (NCS) patients (p=0.006). Moreover, a specific excess of family history of psychotic disorder was found in CS patients, but not of any other psychiatric disorder, as well as an earlier age at exposure to cannabis (16.7+/-2.5 yr, p=0.03). Sensitivity to psychotogenic effects of cannabis in schizophrenia patients could be related to both genetic vulnerability to schizophrenia and the influence of cannabis on brain maturation and could modulate the influence of cannabis on the onset of schizophrenia.

Deficit of inhibition motor control in untreated patients with schizophrenia: Further support from visually guided saccade paradigms

In addition to classical delusional, negative, and cognitive deficit, schizophrenia has consistently been associated with impairments in saccadic eye movements, e.g., an increased error rate in the antisaccade task. We hypothesized that a deficit in inhibitory control is a core defect in untreated patients with schizophrenia leading to impairment in different oculomotor paradigms. Ten drug-free or drug-naïve patients with schizophrenia were matched in age and gender to 11 healthy controls with no psychoactive substance use or abuse. They were explored using reflexive saccades with unpredictable targets with or without the gap procedure, predictive saccades and a fixation/distracter paradigm. Patients with schizophrenia displayed shorter latency in reflexive and predictive saccades. In the GAP condition, patients made more anticipatory saccades, fewer regular saccades, and had a shorter latency of express saccades than controls. In addition, patients had an increased error rate in the fixation/distracters task. Altogether, these results provide new evidence of reduced prefrontal inhibitory regulation of subcortical and brainstem systems involved in the control of saccades.

Preattentional processes and disorganization in schizophrenia: Influence of a 6-week risperidone treatment.

INTRODUCTION Visual orientation and attention are impaired in schizophrenia. Engagement and disengagement of attention and the ability to prompt responses to a stimulus in patients before and after six weeks of risperidone were compared to controls. METHODS Ten unmedicated (nine naïve) schizophrenic patients, and eleven controls performed 1) A visual orienting task, the Cued Target Detection task (CTD), with the detection of a visual stimulus in valid, invalid, no cue and double cue trials, two conditions for fixation offset for a modulation of visual fixation: Gap: 200 ms before target; No Gap: simultaneous with target, 2) Choice Reaction Time (CRT 0.5 and 2 s delays). RESULTS At baseline, patients showed longer RT than controls in CRT, but not in CTD, with in CTD, no facilitation of RT with the gap procedure. The alertness index was almost null in CTD-Gap and comparable to controls in CTD-No Gap. Efficiency to detect attended stimuli (CTD-No Gap) and warning effect (CRT 0.5 s) were negatively correlated to disorganization. After treatment, readiness to act in CRT had decreased. In CTD-No Gap, change in PANSS disorganization was correlated to an increased validity index, change in negative sub-score was correlated to decreased attention cost. CONCLUSION Untreated patients displayed a deficit of Gap effect and a slowing in sustained attention. Disorganization interfered with warning and visual detection. After treatment, its improvement and negative symptoms improvement were associated with better visual detection. These alterations in visual orienting provide new evidence for an oculomotor dysregulation of attentional engagement in schizophrenia.

Consommations de substances illicites chez les étudiants : une enquête en service de médecine préventive

Resume La question de la consommation de substances addictives en population etudiante et des eventuels retentissements psychiques dans cette population d’adultes jeunes est une question importante en termes de sante publique. Differentes donnees epidemiologiques attestent que le cannabis est la principale substance illicite consommee. De plus, certaines donnees tendent a montrer qu’il existe une relation entre consommation de cannabis et survenue de troubles psychiques ulterieurs notamment de nature psychotique. Ces enjeux ont amene une collaboration entre deux partenaires : le Service Inter-Universitaire de Medecine Preventive et de Promotion de la Sante de Paris (SIUMPPS) et le Laboratoire de Physiopathologie de Maladies Psychiatriques (Inserm U894) afin de realiser une enquete epidemiologique sur la consommation de substances illicites en population etudiante. Des resultats preliminaires portant sur un sous-echantillon de cette etude sont presentes. Les perspectives en termes de demarche de prevention et de prise en charge qui pourraient se degager tant des donnees issues de la litterature que des premiers resultats sont discutees.

Effet antidépresseur de la kétamine : revue de la littérature sur l’utilisation de la kétamine dans la dépression

BACKGROUND Depressive disorders have a major impact on public health. They are prevalent and disabling, with high economic burden for society. Antidepressants have a delayed action and at least one third of patients do not achieve adequate response. The recent discovery of ketamines unique antidepressant properties, with rapid onset of response and high rate of responders opens new perspectives for treatment-resistant depression (TRD). METHOD The aim of this article is to summarize preclinical trials and clinical trials demonstrating ketamine antidepressant properties and to review the different modalities of use. RESULTS Most clinical studies used ketamine with a single subanesthetic intravenous administration in patients with treatment-resistant depression, demonstrating a rapid but transient antidepressant response with high response rates. To prevent relapse and maintain the initial benefits, few studies have shown the interest of serial infusions of ketamine, while others combined ketamine and electroconvulsive therapy using the former as an anesthetic. So far, relay treatments with glutamatergic agents such as riluzole are disappointing. Although most studies were conducted in patients with TRD in recurrent depression or bipolar disorder, efficacy in acutely suicidal patients is promising. CONCLUSION Our review highlights the increasing interest in the use of ketamine in the treatment of treatment-resistant depression. Although a widespread use of ketamine as an antidepressant in routine clinical settings seems limited by psychotomimetic effects and the lack of strategy to maintain initial benefits, ketamine or related drugs might be used to target specific conditions, such as bipolar depression or high suicide risk.

Effet antidépresseur de la kétamine : revue de la littérature sur les mécanismes d’action de la kétamine

BACKGROUND In recent years, discovery of ketamines fast and powerful antidepressant effects for treatment-resistant depression (TRD) has led to rethinking of the pathophysiology of depression. Numerous studies in humans and animals have focused on mechanisms of action underlying this effect, producing a number of explanatory pathways. METHOD The aim of this article is to summarize the various hypotheses underlying rapid antidepressant action of ketamine and therefore to better understand the mechanisms underlying depression and antidepressant action. RESULTS Ketamine unique antidepressant properties have led to many studies on its neurobiological grounds. Intracellular signaling pathways such as mTOR, GSK3 or eEF2 seem to play a key role and are associated with an increased synaptic plasticity. Other hypotheses are discussed such as ketamine effects on neuro-inflammation, the role of anterior cingulate cortex in brain changes induced by ketamine, and the potential benefits of analgesic properties of ketamine in depressive disorders. CONCLUSION Our review highlights the potential role of the glutamatergic system in the pathophysiology and treatment of mood disorders. Understanding which pathways underlie the fast antidepressant effect of ketamine paves the way for the development of new antidepressants.

Traitement par électroconvulsivothérapie d’une tétraplégie par conversion hystérique : à propos d’un cas

UNLABELLED Conversion disorder refers to the occurrence of neurological-like symptoms or deficits that are neither intentionally produced nor simulated. While it cannot be explained by an organic disease, it is often related to psychological events. CASE REPORT We report the case of a 33-year-old patient with a fluctuating hysterical tetraplegia, which had started three years earlier. After the failure or the exhaustion of several biological (psychotropic medication, transcranial magnetic stimulation) and psychotherapeutic strategies, treatment with electroconvulsive therapy (ECT) was conducted. A total of thirty-five ECT sessions were performed. Whereas the patients clinical state was initially characterized by a complete quadriplegia and an uncontrollable muscular hypertonia, we noted that the ECT sessions were associated with a slow, though remarkable, progress. At first, the sessions were followed by moments of altered consciousness during which the patient would be relaxed and could make simple movements. Secondarily, not only was our patient able to consciously move his four limbs, but he was also able to walk. However, those improvements remained partial and fluctuating, sometimes allowing the symptom to return temporarily secondary to frustrations or annoyances. Finally, our patient relapsed. Nevertheless, his clinical state presently remains better than that in which we first knew him. DISCUSSION The treatment of conversion disorders has been the subject of few studies and predominantly remains symptomatic. Its main goals are: to lessen secondary gains impact by adopting a neutral behaviour towards the symptom and by encouraging physical rehabilitation; to lower the symptom by allowing the patient to understand the normal functioning of the diseased organ, and; to help the patient to deal with stressful situations. There is no evidence that hypnosis is superior to medical and other psychotherapeutic approaches. Pharmacological treatments may be helpful in the case of anxiety, impulsivity or depression, albeit delivered with caution. According to some case reports, transcranial magnetic stimulation has also been associated with clinical remission. Although the use of ECT in motor conversion disorders constitutes an uncommon procedure, and even if no clinical trial has evaluated its impact on such a pathological condition, several case reports suggest that electroconvulsive therapy can be efficient in the treatment of motor conversion disorders. This efficacy may rely on several hypotheses. ECT could induce neural modifications, and participate in the suppression of an active inhibition, which is responsible for hysterical symptoms. Indeed, conversion cerebral disorder correlates can be explored with the help of functional neuro-imaging techniques, which could therefore also identify ECT neural effects. ECT adverse effects on memory could lead to a new relationship with the symptom, and modulate the psychological conflict which has participated in its emergence. Narcoanalysis, ECT sessions could have an impact on consciousness by means of some dissolution and reorganization phenomenon. It could therefore participate in the ending of an emotional block, the psychic integration of traumatic events and the recovery of a voluntary motor control. Finally, ECT could be efficient thanks to its antidepressant properties, especially its ability to stimulate triaminergic, and particularly dopaminergic transmission. This case report reminds us how difficult it can be to deal with severe conversion disorders, and to navigate between two reefs, which are abstention, and therapeutic escalation.

Intérêt de l’électroconvulsivothérapie de maintenance dans les troubles de l’humeur

Maintenance electroconvulsive therapy (M-ECT) is a treatment indicated for the treatment and prevention of recurrent depression in patients who either do not respond or do not tolerate psychotropic medication. We evaluated, retrospectively, clinical response to a 6-month minimum course of M-ECT in 25 patients with a diagnosis of bipolar disorder or schizoaffective disorder according to DSM IV-TR criterion. Our study demonstrated a significant improvement of Global Assessment of functioning (GAF) scores after a six month minimum course of M-ECT (34.8 ± 12.6 vs 65.6 ± 10.8; P<0.05) as well as Brief Psychiatric Rating Scale scores (BPRS): 79.3 ± 12.4 vs 43.4 ± 10.2; P<0.05). We observed a slight increase of Mini Mental State Examination (MMSE) scores after M-ECT; nonetheless, it was not statistically significant (24.2 ± 2.4 vs 26.2 ± 2.4; P=0.2). Regarding the mean duration of hospitalizations, we showed a statistically significant decrease in the median number of days of hospitalization (72 [59-93.50] days before M-ECT vs 43 [25-76] days since the first M-ECT; P=0.017). Maintenance ECT allowed a significant improvement in psychiatric symptoms and global functioning of the patients included in this study, as well as a decrease in the number of days of hospitalization. However, our pattern is limited because of its small size; so, further prospective studies in this field, including larger population is highly recommended.

Applications thérapeutiques de l’ocytocine dans l’autisme : premiers résultats et pistes de recherche

The neuropeptide oxytocin (OT) is an evolutionary highly conserved molecule that plays a part in the regulation of complex social cognition and behaviours. From a pathophysiological point of view, several studies have evidenced dysfunctions of the oxytocinergic system in autism spectrum disorders (ASD): a lowering of plasma OT and genetic or epigenetic anomalies of the OT receptor. Therefore, some authors have hypothesized that an abnormality in the OT neurotransmission may account for several features of autism and that a treatment restoring a normal OT pathway functioning could improve social abilities. OT administration has thus been used in clinical trials, especially in groups of subjects suffering from autism. Some studies found that OT decreased repetitive behaviours, enhanced emotional understanding of speech intonation, improved performance of the Reading the Mind in the Eyes Test and reinforced cooperation. Nevertheless, the findings of the OT administration studies on clinical samples show great diversity. The context, the personality and childhood experiences of the subject could be moderators influencing the effect of exogenous OT. Besides, three mechanisms could play a part in the action of OT on ASD social symptoms: anxiety reduction (with a lowering in the hypothalamic-pituitary-adrenal axis responsiveness and in the amygdale reactivity to social stimuli), increased affiliative motivation (involving the dopaminergic pathway and several regions of the social brain) and enhanced perceptual selectivity and social stimuli salience. To conclude, OT could be a promising molecule used as a treatment to promote social behaviours, helping individuals with ASD to develop new relationships. OT could be administered during a cognitive-behavioural therapy to reinforce the efficacy of such procedures. More studies are needed, on larger samples, to investigate the safety and efficacy of OT administration and to specify optimal dosages and characteristics of patients who may benefit from this treatment.