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Patients with psychiatric disorders have a decrease in their life expectancy. Excess mortality of patients with schizophrenia was demonstrated by a meta-analysis in the late 1990s and has not decreased for the past 30years. A recent meta-analysis including nearly 250,000 patients with schizophrenia found an average decrease in life expectancy of 14.5years (CI95: 11,2-17,8), more important for men than for women: 15.9 (CI95: 13,8-18,0) vs 13.6 (CI95: 11,4-15,8). A closer look at the somatic comorbidities, including metabolic syndrome, and investigation of causes of death of these patients highlighted already well-known factors, namely late diagnosis and insufficient treatment of physical diseases, side effects of antipsychotics, unhealthy lifestyle (poor diet, smoking, excessive alcohol consumption and lack of exercise), and higher risk of suicide and accident. Concerning ultra-high risk (UHR) patients, a 2016 meta-analysis of 47 studies evaluated the cardiovascular risk factors. They reported a higher prevalence of smoking in UHR (odds ratio 2,3) and a lower level of physical activity associated with a normal BMI (Body Mass Index) compared to the control population. A meta-analysis about patients with a first episode of psychosis (FEP) found reduced total and LDL cholesterol levels and an increased triglyceride level compared to the control population. One study found alteration of the fasting plasmatic levels of glucose and insulin, as well as insulin resistance in FEP patients, compared to controls albeit the HbA1c level was not significantly different. A meta-analysis reported a prevalence of metabolic syndrome of 10 % in FEP or drug naïve patients versus 35 % and 20 % in treated and untreated patients with chronic schizophrenia respectively. Somatic comorbidities usually appear during the first two years of the disease. Some interventions have proven their efficacy in reducing the occurrence of metabolic syndrome and other cardiovascular risk factors. For instance, metformin, a treatment for type 2 diabetes that is allowed from the age of 10, has shown benefits in children and adolescents receiving second-generation antipsychotics in a recent meta-analysis, with a mean weight loss of 3.23kg (IC95 % -5.59 -0.86) after 16 weeks. Dietary-hygienic interventions are also effective in reducing cardiovascular risk. Other interventions such as omega-3 supplementation, vitamin D, N-acetylcysteine, and fasting have not proven to be effective. Comprehensive care programs have been developed to promote somatic care in psychiatric patients, such as the Canadian HeAL (Healthy Active Lives) program. These programs are more effective when proposed from the beginning of the disease and the introduction of antipsychotics. In this review, because there is no French recommendation, we translate a tool for the prescription of metformin and the Canadian recommendations from the HeAL program. Generalization of these programs to all young psychotic patients could improve their life expectancy and reduce the overall mortality. Prevention of cardiovascular risk factors and cardio-metabolic monitoring of treatments must be part of the standard of care in early psychosis. These programs aim at providing patients with the quality of somatic and mental care they are entitled to. This requires the involvement of all stakeholders, including patients and their families but also psychiatrists and other caregivers., (Copyright © 2020 L'Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.)

The various roles of membrane lipids in human health has urged researchers to study their impact in neuropsychiatric diseases, especially in schizophrenia spectrum disorders and more recently in early stages of psychosis. The progress in mass spectrometry technologies now allows a more comprehensive analysis of phospholipids (PL) and their fatty acid (FA) molecular species. FA are defined by a carbon chain of variable length and are said to be unsaturated when their chain has one or more carbon-carbon double bonds. The PL are composed of a hydrophilic polar head with a phosphoric acid group and an hydrophobic part with FAs; they encompass glycerophospholipids and sphingolipids. The plasma membrane is a complex and dynamic structure consisting of a lipid bilayer composed of an outer layer and an inner layer of specific lipid composition. The permanent remodeling of membrane lipids involves phospholipases especially the phospholipase A2. Seventy percent of the brain consists of lipids from different classes and molecular species. Most of the brain lipids are composed of polyunsaturated fatty acid (PUFA)-enriched diacyl classes where omega-3 and omega-6 molecular species predominate. The balance between omega-3 and omega-6 is important for the neurodevelopment. PUFA are also involved in neurogenesis and neurotransmission. Sphingomyelin (SM) is a sphingolipid that influences inflammation, cell proliferation and lipid rafts formation. It is an important component of myelin sheaths of white matter and therefore is involved in cerebral connectivity. In rat models, deficiency in omega-3 causes abnormalities in dopaminergic neurotransmission, impacts on the functioning of some receptors (including cannabinoids CB1, glutamatergic N-methyl-D-aspartate receptor, NMDA), and increases sensitivity to hallucinogens. In contrast, omega-3 supplementation improves cognitive function and prevents psychotic-like behavior in some animal models for schizophrenia. It also reduces oxidative stress and prevents demyelination. The historical membrane hypothesis of schizophrenia has led to explore the lipids abnormality in this disorder. This hypothesis was initially based on the observation of an abnormal membrane prostaglandin production in schizophrenia caused by a membrane arachidonic acid deficiency. It has evolved emphasizing the various PUFA membrane's roles in particular regarding oxidative stress, inflammation and regulation of the NMDA receptors. In patients with mental disorders, low omega-3 index is more frequent than in the general population. This lipid abnormality could lead to myelination abnormalities and cognitive deficits observed in patients. It could also participate in oxidative stress abnormalities and inflammation reported in schizophrenia. On the other hand, low omega-3 index deficit was reported to be associated with an increased cardiovascular risk, and omega-3 supplementation may also have a positive cardiovascular impact in psychiatric patients, even more than in the general population. The presence of membrane lipid abnormalities is also found in patients during the first psychotic episode (FEP). The omega-3 supplementation improved the recovery rate and prevented the loss of gray matter in FEP. In patients at ultra-high risk to develop a psychotic disorder (UHR), omega-3 supplementation has been associated with a reduction of the rate of conversion to psychosis and with metabolic changes, such as decreased activity of phospholipase A2. However, this study has not as yet been replicated. Not all patients exhibit lipid abnormalities. Several studies, including studies from our team, have found a bimodal distribution of lipids in patients with schizophrenia. But some studies have found differences (in PUFA) in the acute phase whereas our studies (on phospholipids) are in chronic phases. It will be interesting to study in more depth the links between these two parameters. Furthermore, we identified a subgroup which was identified with a deficit in sphingomyelin and PUFA whereas others have found an increase of sphingomyelin. Individuals with this abnormal lipid cluster had more cognitive impairments and more severe clinical symptoms. Because the niacin test is an indirect reflection of arachidonic acid levels, it has been proposed to identify a subset of patients with membrane lipids anomalies. Niacin test response is influenced by several factors related to lipid metabolism, including cannabis use and phospholipase A2 activity. Despite progress, the function and impact of membrane lipids are still poorly understood in schizophrenia. They could serve as biomarkers for identifying biological subgroups among patients with schizophrenia. In UHR patients, their predictive value on the conversion to psychosis should be tested. Omega-3 supplementation could be a promising treatment thanks to its good tolerance and acceptability. It could be more appropriate for patients with PUFA anomalies in a more personalized medical approach., (Copyright © 2020 L'Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.)

The exact modalities of switching between two antipsychotics are rarely studied despite the high frequency of this issue in clinical practice. In this context, description of clinical cases may be enlightening. We report on three new cases of agitation after replacing a dopaminergic antagonist with aripiprazole. A literature review indicated no other predictive clinical feature associated with a higher risk of agitation than therapeutic history. In fact, patients who previously received a greater dose of antipsychotic are more at risk to present paradoxical agitation when switching to aripiprazole. This has led to the hypothesis of dopaminergic hypersensitivity: dopaminergic antagonists could increase the number of receptors to be activated by a partial agonist-like aripiprazole. In one of the cases described here, the patient had received aripiprazole two years previously without any particular side effects. The reintroduction of aripiprazole after a treatment by risperidone was followed by agitation. Other pharmacological hypotheses to explain this agitation involve cholinergic and histaminergic rebounds as well. The frequency of these paradoxical reactions is probably underreported, and psychiatrists should be more attentive to them. During the replacement, aripiprazole should be prescribed at the maximal posology from the start, and the previous antipsychotic should be maintained and slowly decreased in no fewer than four weeks., (Copyright © 2017 L'Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.)

Background: Psychiatric disorders are consistent with the gene x environment model, and non-specific environmental factors such as childhood trauma, urbanity, and migration have been implicated. All of these factors have in common to dysregulate the biological pathways involved in response to stress. Stress is a well-known precipitating factor implicated in psychiatric disorders such as depression, bipolar disorder, anxiety, and possibly schizophrenia. More precisely, psychosocial stress induces dysregulation of the hypothalamic-pituitary-adrenal axis (HPA) and could modify neurotransmission, which raises the question of the involvement of stress-related biological changes in psychotic disorders. Indeed, the literature reveals dysregulation of the HPA axis in schizophrenia. This dysregulation seems to be present in the prodromal phases (UHR subjects for ultra-high risk) and early schizophrenia (FEP for first episode psychosis). Thus, and following the stress-vulnerability model, stress could act directly on psychotic onset and precipitate the transition of vulnerable subjects to a full-blown psychosis., Objective: The present paper reviews the literature on stress and onset of schizophrenia, with consideration for the causal role vs. associated role of HPA axis dysregulation in schizophrenia and the factors that influence it, in particular during prodromal and earlier phases. We also discuss different methods developed to measure stress in humans., Methodology: We performed a bibliographic search using the keywords 'cortisol', 'glucocorticoid', 'HPA' with 'UHR', 'CHR', 'at-risk mental state', 'first episode psychosis', 'schizotypal', 'prodromal schizophrenia' in Medline, Web of Knowledge (WOS), and EBSCO completed by a screening of the references of the selected articles., Results: Stress has been studied for many years in schizophrenia, either by subjective methods (questionnaires), or objective methods (standardized experimental protocols) with biological sampling and/or brain imaging methods. These methods have suggested a link between dysregulation of the HPA axis and psychotic symptoms both through abnormal basal levels of cortisol and flattened reactivity to social stress. Imaging results suggest indirect modifications, including abnormal pituitary or hippocampal volume. Several factors dysregulating the HPA axis have also been highlighted, such as consumption of drugs (i.e. cannabis), childhood trauma or genetic factors (such as COMT, or MTHFR variants). Psychological stress induces subcortical dopaminergic activation attributable to hypothalamic-pituitary-adrenal (HPA) axis dysregulation. This dysregulation is present in the prodromal phase (UHR) in patients who have experienced a first psychotic episode (FEP) and in siblings of schizophrenic patients. Stress dysregulation is a plausible hypothesis to understand the psychosis onset., Discussion: The effect of stress on brain pathways could participate to the mechanisms underlying the onset of psychotic symptoms, both as a precipitating factor and as a marker of a predisposing vulnerability. This dysregulation fits into the gene x environment model: in subjects with genetic predispositions, stressful environmental factors can modify biological pathways implicated in psychiatric disorders, promoting the emergence of symptoms. However, many confounding factors obscure the literature, and further studies are needed in schizophrenic patients, UHR and FEP patients to clarify the precise role of stress in psychotic transition. Identification of stress biomarkers could help diagnosis and prognosis, and pave the way for specific care strategies based on stress-targeted therapies., (Copyright © 2016 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.)

Background: Schizophrenia is a frequent and disabling disease associated with heterogeneous psychiatric phenotypes. It emerges during childhood, adolescence or young adulthood and has dramatic consequences for the affected individuals, causing considerable familial and social burden, as well as increasing health expenses. Although some progress has been made in the understanding of their physiopathology, many questions remain unsolved, and the disease is still poorly understood. The prevailing hypothesis regarding psychotic disorders proposes that a combination of genetic and/or environmental factors, during critical periods of brain development increases the risk for these illnesses. Epigenetic regulations, such as DNA methylation, can mediate gene x environment interactions at the level of the genome and may provide a potential substrate to explain the variability in symptom severity and family heritability. Initially, epigenetics was used to design mitotic and meiotic changes in gene transcription that could not be attributed to genetic mutations. It referred later to changes in the epigenome not transmitted through the germline. Thus, epigenetics refers to a wide range of molecular mechanisms including DNA methylation of cytosine residues in CpG dinucleotides and post-translational histone modifications. These mechanisms alter the way the transcriptional factors bind the DNA, modulating its expression. Prenatal and postnatal environmental factors may affect these epigenetics factors, having responsability in long-term DNA transcription, and influencing the development of psychiatric disorders., Object: The object of this review is to present the state of knowledge in epigenetics of schizophrenia, outlining the most recent findings in the matter., Methods: We did so using Pubmed, researching words such as 'epigenetics', 'epigenetic', 'schizophrenia', 'psychosis', 'psychiatric'. This review summarizes evidences mostly for two epigenetic mechanisms: DNA methylation and post-translational histone modifications., Results: First, in terms of epidemiology and transmission, the theoretical model of epigenetics applies to schizophrenia. Then, most environmental factors that have proved a link with this disease, may generate epigenetic mechanisms. Next, mutations have been found in regions implied in epigenetic mechanism among populations with schizophrenia. Some epigenetic alterations in DNA regions have been previously linked with neurodevelopmental abnormalities. In psychosis, some authors have found methylation differences in COMT gene, in reelin gene and in some genes implicated in dopaminergic, serotoninergic, GABAergic and glutamatergic pathways. Histone modifications have been described, in particular the H3L4 histone methylation. Finally, we tried to underline the difficulties in epigenetic research, notably in psychiatry, and the limits in this matter., Conclusion: The epigenetic field may explain a lot of questions around the physiopathology of the complex psychiatric disease that is schizophrenia. It may be a substratum to the prevailing hypothesis of gene x environment interaction. The research in the matter is definitely expanding. It justifies easily the need to improve the effort in the domain to overpass some limits inherent to the matter., (Copyright © 2014 L’Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.)