Basal low antioxidant capacity correlates with cognitive deficits in early onset psychosis. A 2-year follow-up study

N-acetylcysteine during critical neurodevelopmental periods prevents behavioral and neurochemical deficits in the Poly I:C rat model of schizophrenia

Schizophrenia is a chronic neurodevelopmental disorder with an inflammatory/prooxidant component. N-acetylcysteine (NAC) has been evaluated in schizophrenia as an adjuvant to antipsychotics, but its role as a preventive strategy has not been sufficiently explored. We aimed to evaluate the potential of NAC administration in two-time windows before the onset of symptoms in a schizophrenia-like maternal immune stimulation (MIS) rat model. Pregnant Wistar rats were injected with Poly I:C or Saline on gestational day (GD) 15. Three different preventive approaches were evaluated: 1) NAC treatment during periadolescence in the offspring (from postnatal day [PND] 35 to 49); 2) NAC treatment during pregnancy after MIS challenge until delivery (GD15-21); and 3) NAC treatment throughout all pregnancy (GD1-21). At postnatal day (PND) 70, prepulse inhibition (PPI) and anxiety levels were evaluated. In vivo magnetic resonance (MR) imaging was acquired on PND100 to assess structural changes in gray and white matter, and brain metabolite concentrations. Additionally, inflammation and oxidative stress (IOS) markers were measured ex vivo in selected brain regions. MIS offspring showed behavioral, neuroanatomical, and biochemical alterations. Interestingly, NAC treatment during periadolescence prevented PPI deficits and partially counteracted some biochemical imbalances. Moreover, NAC treatments during pregnancy not only replicated the beneficial outcomes reported by the treatment in periadolescence, but also prevented some neuroanatomical deficits, including reductions in hippocampal and corpus callosum volumes. This study suggests that early reduction of inflammation and prooxidation could help prevent the onset of schizophrenia-like symptoms, supporting the importance of anti-IOS compounds in ameliorating this disorder.

DNA methylation at birth and lateral ventricular volume in childhood: a neuroimaging epigenetics study

BACKGROUND

Lateral ventricular volume (LVV) enlargement has been repeatedly linked to schizophrenia; yet, what biological factors shape LVV during early development remain unclear. DNA methylation (DNAm), an essential process for neurodevelopment that is altered in schizophrenia, is a key molecular system of interest.

METHODS

In this study, we conducted the first epigenome-wide association study of neonatal DNAm in cord blood with LVV in childhood (measured using T1-weighted brain scans at 10 years), based on data from a large population-based birth cohort, the Generation R Study (N = 840). Employing both probe-level and methylation profile score (MPS) approaches, we further examined whether epigenetic modifications identified at birth in cord blood are: (a) also observed cross-sectionally in childhood using peripheral blood DNAm at age of 10 years (Generation R, N = 370) and (b) prospectively associated with LVV measured in young adulthood in an all-male sample from the Avon Longitudinal Study of Parents and Children (ALSPAC, N = 114).

RESULTS

At birth, DNAm levels at four CpGs (annotated to potassium channel tetramerization domain containing 3, KCTD3; SHH signaling and ciliogenesis regulator, SDCCAG8; glutaredoxin, GLRX) prospectively associated with childhood LVV after genome-wide correction; these genes have been implicated in brain development and psychiatric traits including schizophrenia. An MPS capturing a broader epigenetic profile of LVV - but not individual top hits - showed significant cross-sectional associations with LVV in childhood in Generation R and prospectively associated with LVV in early adulthood within ALSPAC.

CONCLUSIONS

This study finds suggestive evidence that DNAm at birth prospectively associates with LVV at different life stages, albeit with small effect sizes. The prediction of MPS on LVV in a childhood sample and an independent male adult sample further underscores the stability and reproducibility of DNAm as a potential marker for LVV. Future studies with larger samples and comparable time points across development are needed to further elucidate how DNAm associates with this clinically relevant brain structure and risk for neuropsychiatric disorders, and what factors explain the identified DNAm profile of LVV at birth.

Schizophrenia and Glutathione: A Challenging Story

Schizophrenia (SZ) is a devastating mental illness with a complex and heterogeneous clinical state. Several conditions like symptoms, stage and severity of the disease are only some of the variables that have to be considered to define the disorder and its phenotypes. SZ pathophysiology is still unclear, and the diagnosis is currently relegated to the analysis of clinical symptoms; therefore, the search for biomarkers with diagnostic relevance is a major challenge in the field, especially in the era of personalized medicine. Though the mechanisms implicated in SZ are not fully understood, some processes are beginning to be elucidated. Oxidative stress, and in particular glutathione (GSH) dysregulation, has been demonstrated to play a crucial role in SZ pathophysiology. In fact, glutathione is a leading actor of oxidative-stress-mediated damage in SZ and appears to reflect the heterogeneity of the disease. The literature reports differing results regarding the levels of glutathione in SZ patients. However, each GSH state may be a sign of specific symptoms or groups of symptoms, candidating glutathione as a biomarker useful for discriminating SZ phenotypes. Here, we summarize the literature about the levels of glutathione in SZ and analyze the role of this molecule and its potential use as a biomarker.

Prospective memory in early and established psychosis: An Indian perspective

Individuals affected by psychosis often have deficits in several neurocognitive functions. Prospective memory (PM), the ability to remember to do things, is crucial for activities of daily living, social and occupational functioning, but very few studies have attempted to examine this domain of functioning in people with psychosis, particularly in India. A total of 71 patients with psychosis, (both early and established psychosis), and 140 age, gender and education-matched healthy controls were assessed using the Positive and Negative Symptom Scale, Hospital Anxiety and Depression scale, and Addenbrooke's Cognitive Examination. PM was assessed using the Cambridge Prospective Memory Test and the Prospective and Retrospective Memory Questionnaire (PRMQ). Group differences were evaluated using Mann-Whitney U-tests. Significantly greater cognitive deficits, higher anxiety and depression were evident in the psychosis group compared with controls. The psychosis group performed significantly poorer on both time- and event-based tests in CAMPROMPT than controls. These differences remained when controlling for age, education, general cognitive functioning and mood. The subjective measure of PM (PRMQ) did not differentiate the two groups. The PM performance of early and established psychosis patients was similar. Comparisons with cross-cultural data (PRMQ UK norms and CAMPROMPT and PRMQ Chinese data) revealed important differences in PM performance. Individuals with psychosis have significant deficits in both time- and event-based PM. CAMPROMPT emerged as a more sensitive PM measure compared with PRMQ. Results from cross-cultural comparisons underscore the need for cultural contextualization of assessments.

Age of Onset Moderates the Association between Total Antioxidant Capacity and Cognitive Deficits in Patients with Drug-Naïve Schizophrenia

Schizophrenia patients with an earlier age of onset have been found to have more serious negative symptoms and cognitive deficits. Oxidative stress is thought to be implicated in cognitive impairment in schizophrenia. Total antioxidant capacity (TAOC) is an essential indicator of oxidative stress. However, the association between age of onset, TAOC, and cognitive performance in schizophrenia remains unexplored. In this study, 201 patients (age: 26.5 ± 9.6 years; male: 53.2%) with drug-naïve schizophrenia were recruited. Clinical symptoms were evaluated using the Positive and Negative Syndrome Scale (PANSS). Cognitive functioning was assessed using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Plasma TAOC levels were analyzed using established procedures. Results showed that early-onset (EO) patients had higher TAOC levels, more severe negative symptoms and performed worse on visuospatial/constructional, language and RBANS total scores than non-EO patients. After Bonferroni correction, only non-EO patients showed a significant inverse relationship between TAOC levels and RBANS language, attention, and total scores. Our findings suggest that an early/late age of onset may be correlated with psychopathological symptoms, cognitive impairment and oxidative responses in schizophrenia. Furthermore, the age of onset may moderate the relationship between TAOC and cognitive function in patients with schizophrenia. These findings suggest that improving oxidative stress status in non-EO schizophrenia patients may enhance their cognitive function.

Oxidative Stress Biomarkers among Schizophrenia Inpatients

Background. Finding the associations between schizophrenia symptoms and the biomarkers of inflammation, oxidative stress and the kynurenine pathway may lead to the individualization of treatment and increase its effectiveness. Methods. The study group included 82 schizophrenia inpatients. The Positive and Negative Symptoms Scale (PANSS), the Brief Assessment of Cognition in Schizophrenia (BACS) and the Calgary Depression in Schizophrenia Scale were used for symptom evaluation. Biochemical analyses included oxidative stress parameters and brain-derived neurotrophic factor (BDNF). Results. Linear models revealed the following: (1) malondiadehyde (MDA), N-formylkynurenine (N-formKYN), advanced oxidation protein products (AOPP), advanced glycation end-products of proteins (AGE) and total oxidative status (TOS) levels are related to the PANSS-total score; (2) MDA, reduced glutathione (GSH) and BDNF levels are related to the PANSS-negative score; (3) TOS and kynurenine (KYN) levels are related to the PANSS-positive score; (4) levels of total antioxidant status (TAS) and AOPP along with the CDSS score are related to the BACS-total score; (5) TAS and N-formKYN levels are related to the BACS-working memory score. Conclusions. Oxidative stress biomarkers may be associated with the severity of schizophrenia symptoms in positive, negative and cognitive dimensions. The identification of biochemical markers associated with the specific symptom clusters may increase the understanding of biochemical profiles in schizophrenia patients.

Oxidative stress parameters and antioxidants in adults with unipolar or bipolar depression versus healthy controls: Systematic review and meta-analysis

BACKGROUND

To study differences in oxidative stress markers and antioxidants among patients with bipolar depression (BPD) and unipolar depression (UPD).

METHODS

Data sources. Electronic MEDLINE/PubMed/Cochrane Library/Scopus/TripDatabase database search until 30/06/2021.

STUDY SELECTION

Included were articles comparing antioxidant or oxidative stress markers between adults with BPD or UPD and healthy controls (HCs).

DATA EXTRACTION

Two authors extracted data independently. Random effects meta-analysis, calculating standardized mean differences for results from ≥3 studies.

RESULTS

Oxidative stress markers reported in 40 studies -1 published repeatedly- (UPD, studies = 30 n = 3072; their HCs, n = 2856; BPD, studies = 11 n = 393; their HCs, n = 540; with 1 study reporting on both UPD and BPD) included thiobarbituric acid reactive substances (TBARS), antioxidant uric acid and antioxidant-enhancing enzymes superoxide dismutase (SOD), catalase (CAT) and glutathione-peroxidase (GPX). Compared with HCs, UPD and BPD were associated with significantly higher levels of TBARS, without differences between UPD and BPD (P = 0.11). Compared with HCs, UPD and BPD did not differ regarding the activity of the CAT (P = 0.28), SOD (P = 0.87) and GPX (P = 0.25) enzymes. However, uric acid levels were significantly higher vs HCs in BPD than in UPD among adult patients (P = 0.004). Results were heterogenous, which, for some parameters, decreased after stratification by the blood source (serum, plasma red blood cells, whole blood).

LIMITATIONS

The main limitations are the small number of studies/participants in the BPD subgroup, and heterogeneity of the results.

SUMMATIONS

Both BPD and UPD may be associated with an impaired oxidative stress balance, with significantly higher uric acid levels vs. HCs in UPD than in BPD.

Oxidative Stress and Emergence of Psychosis

Treatment and prevention strategies for schizophrenia require knowledge about the mechanisms involved in the psychotic transition. Increasing evidence suggests a redox imbalance in schizophrenia patients. This narrative review presents an overview of the scientific literature regarding blood oxidative stress markers’ evolution in the early stages of psychosis and chronic patients. Studies investigating peripheral levels of oxidative stress in schizophrenia patients, first episode of psychosis or UHR individuals were considered. A total of 76 peer-reviewed articles published from 1991 to 2022 on PubMed and EMBASE were included. Schizophrenia patients present with increased levels of oxidative damage to lipids in the blood, and decreased levels of non-enzymatic antioxidants. Genetic studies provide evidence for altered antioxidant functions in patients. Antioxidant blood levels are decreased before psychosis onset and blood levels of oxidative stress correlate with symptoms severity in patients. Finally, adjunct treatment of antipsychotics with the antioxidant N-acetyl cysteine appears to be effective in schizophrenia patients. Further studies are required to assess its efficacy as a prevention strategy. Redox imbalance might contribute to the pathophysiology of emerging psychosis and could serve as a therapeutic target for preventive or adjunctive therapies, as well as biomarkers of disease progression.

The relationship between cognitive impairment and superoxide dismutase activity in untreated first-episode patients with schizophrenia

Objectives: Cognitive decline is an essential characteristic of schizophrenia and may be due to the disturbance between reactive oxygen species generation and antioxidant capacity. The study aimed to explore the association between cognitive deficits and antioxidant defence parameters in untreated first-episode patients with schizophrenia.Methods: We determined important antioxidant enzymes, total superoxide dismutase (SOD) and manganese SOD (MnSOD), and their relationship with cognitive impairment in 168 untreated patients with first-episode schizophrenia and 168 age- and sex-matched healthy controls. The evaluation of psychopathological symptoms of all patients was based on the Positive and Negative Syndrome Scale (PANSS). We measured cognitive function by the Repeated Battery for the Assessment of Neuropsychological Status (RBANS) and activities of total SOD and MnSOD in all participants.Results: The results showed that untreated patients with first-episode schizophrenia had deficient cognitive functioning in four RBANS indices and total scores, except for the visuospatial/constructional index, as well as higher plasma total SOD activity compared with the control subjects. In addition, significant negative correlations were identified between MnSOD activity and attention index or RBANS total score in patients.Conclusions: Our results suggest that oxidative stress may be partly responsible for cognitive dysfunction in the early course of schizophrenia.

Central Oxidative Stress and Early Vocational Outcomes in First Episode Psychosis: A 7-Tesla Magnetic Resonance Spectroscopy Study of Glutathione

BACKGROUND AND HYPOTHESIS

Following the first episode of psychosis, some patients develop poor social and occupational outcomes, while others display a pattern of preserved functioning. Evidence from preclinical, genetic, and biochemical studies suggest a role for high oxidative stress in poor functional outcomes among patients. The measurement of intracortical glutathione (GSH) using magnetic resonance spectroscopy (MRS) enables investigating the relationship between central antioxidant tone and functional outcomes at the time of first-episode psychosis (FEP). We hypothesized that patients with higher central antioxidant tone at first presentation will have better functional outcomes in early stages of illness.

STUDY DESIGN

We scanned 57 patients with FEP and 30 matched healthy controls and estimated GSH resonance using 7-Tesla MRS. We minimized the confounding effects of illness chronicity, long-term treatment exposure, and metabolic complications by recruiting patients with <2 weeks of lifetime antipsychotic exposure on average and followed up this cohort for the next 1 year to determine functional outcomes.

STUDY RESULTS

Patients who achieved employment/education or training status (EET) in the first year, had higher GSH at the baseline than healthy controls. Social and occupational functioning assessment scale (SOFAS) scores were also significantly higher in patients with higher GSH levels at the outset, after adjusting for various confounds including baseline SOFAS. Patients who were not in EET did not differ from healthy subjects in their GSH levels.

CONCLUSION

Our observations support a key role for the central antioxidant tone in the functional outcomes of early psychosis.

Oxidative Stress in the Early Stage of Psychosis

BACKGROUND

In the past few decades, increasing evidence in the literature has appeared describing the role of the antioxidant defense system and redox signaling in the multifactorial pathophysiology of psychosis. It is of interest to clinicians and researchers alike that abnormalities of the antioxidant defense system are associated with alterations of cellular membranes, immune functions and neurotransmission, all of which have some clinical implications.

METHODS

This narrative review summarizes the evidence regarding oxidative stress in the early stages of psychosis. We included 136 peer-reviewed articles published from 2007 to 2020 on PubMed EMBASE, The Cochrane Library and Google Scholar.

RESULTS

Patients affected by psychotic disorders show a decreased level of non-enzymatic antioxidants, an increased level of lipid peroxides, nitric oxides, and a homeostatic imbalance of purine catabolism. In particular, a significantly reduced antioxidant defense has been described in the early onset first episode of psychosis, including reduced levels of glutathione. Also, it has been shown that a decreased basal low -antioxidant capacity correlates with cognitive deficits and negative symptoms, mostly related to glutamate-receptor hypofunction. In addition, atypical antipsychotic drugs seem to show significant antioxidant activity. These factors are critical in order to treat cases of first-onset psychosis effectively.

CONCLUSION

This systematic review indicates the importance that must be given to anti-oxidant defense systems.

Investigating potential associations between neurocognition/social cognition and oxidative stress in schizophrenia

INTRODUCTION

Deficits in neurocognition and social cognition play a critical role in the functional impairment of patients with schizophrenia. Increased oxidative stress has been evidenced in schizophrenia. Increased oxidative stress can affect neuronal function and lead to impairments in neurocognitive functions (especially working memory) and social cognition.

OBJECTIVE

To investigate deficits in neurocognition and social cognition and their potential association with oxidative stress biomarkers in schizophrenia.

MATERIAL AND METHODS

Eight-five clinically stable patients with schizophrenia and 75 controls were enrolled in this study. Neurocognition was evaluated through the Brief Assessment of Cognition in Schizophrenia (BACS). Social cognition was assessed through the Hinting Task - a test of theory of mind - and an emotion processing test, Facial Emotion Recognition Test (FERT-100). Oxidative stress was assessed by measuring serum levels of glutathione (GSH) and thiobarbituric acid reactive substances (TBARS).

RESULTS

Patients had decreased serum levels of GSH (Z=3.56; p<0.001) and increased TBARS (Z=5.51; P<0.001) when compared with controls. TBARS levels are higher in patients using first generation antipsychotics. Higher serum levels of TBARS in patients were associated with poor performance in working memory test (r=-0.39; p=0.002), even when controlling for age and negative symptoms (Standard Beta: -0.36; CI= -2.52 a -13.71).

DISCUSSION

The association between greater lipid peroxidation, as assessed by TBARS, and worse performance in working memory corroborates theoretical models of greater vulnerability of schizophrenia to oxidative stress.

Predicting individual improvement in schizophrenia symptom severity at 1-year follow-up: Comparison of connectomic, structural, and clinical predictors

In a machine learning setting, this study aims to compare the prognostic utility of connectomic, brain structural, and clinical/demographic predictors of individual change in symptom severity in individuals with schizophrenia. Symptom severity at baseline and 1-year follow-up was assessed in 30 individuals with a schizophrenia-spectrum disorder using the Brief Psychiatric Rating Scale. Structural and functional neuroimaging was acquired in all individuals at baseline. Machine learning classifiers were trained to predict whether individuals improved or worsened with respect to positive, negative, and overall symptom severity. Classifiers were trained using various combinations of predictors, including regional cortical thickness and gray matter volume, static and dynamic resting-state connectivity, and/or baseline clinical and demographic variables. Relative change in overall symptom severity between baseline and 1-year follow-up varied markedly among individuals (interquartile range: 55%). Dynamic resting-state connectivity measured within the default-mode network was the most accurate single predictor of change in positive (accuracy: 87%), negative (83%), and overall symptom severity (77%) at follow-up. Incorporating predictors based on regional cortical thickness, gray matter volume, and baseline clinical variables did not markedly improve prediction accuracy and the prognostic utility of these predictors in isolation was moderate (<70%). Worsening negative symptoms at 1-year follow-up were predicted by hyper-connectivity and hypo-dynamism within the default-mode network at baseline assessment, while hypo-connectivity and hyper-dynamism predicted worsening positive symptoms. Given the modest sample size investigated, we recommend giving precedence to the relative ranking of the predictors investigated in this study, rather than the prediction accuracy estimates.

ENACT: a protocol for a randomised placebo-controlled trial investigating the efficacy and mechanisms of action of adjunctive N-acetylcysteine for first-episode psychosis

Background

First-episode psychosis (FEP) may lead to a progressive, potentially disabling and lifelong chronic illness; however, evidence suggests that the illness course can be improved if appropriate treatments are given at the early stages. Nonetheless, the efficacy of antipsychotic medications is suboptimal, particularly for negative and cognitive symptoms, and more efficacious and benign treatments are needed. Previous studies have shown that the antioxidant amino acid N-acetylcysteine (NAC) reduces negative symptoms and improves functioning in chronic schizophrenia and bipolar disorder. Research is scarce as to whether NAC is beneficial earlier in the course of illness. The primary aim of this study is to determine the efficacy of treatment with adjunctive NAC (2 g/day for 26 weeks) compared with placebo to improve psychiatric symptoms in young people experiencing FEP. Secondary aims are to explore the neurobiological mechanisms underpinning NAC and how they relate to various clinical and functional outcomes at 26- and 52-week follow-ups.

Methods/design

ENACT is a 26-week, randomised controlled trial of adjunctive NAC versus placebo, with a 26-week non-treatment follow-up period, for FEP. We will be recruiting 162 young people aged 15–25 years who have recently presented to, and are being treated at, the Early Psychosis Prevention and Intervention Centre, Melbourne, Australia. The primary outcome is the Total Score on the Positive and Negative Syndrome Scale which will be administered at baseline, and weeks 4, 8, 12, 26 (primary endpoint), and 52 (end of study). Secondary outcomes include: symptomatology, functioning, quality of life, neurocognition, blood-derived measures of: inflammation, oxidative and nitrosative stress, and magnetic resonance spectroscopy measures of glutathione concentration.

Discussion

Targeted drug development for FEP to date has generally not involved the exploration of neuroprotective agents. This study has the potential to offer a new, safe, and efficacious treatment for people with FEP, leading to better treatment outcomes. Additionally, the neuroprotective dimension of this study may lead to a better long-term prognosis for people with FEP. It has the potential to uncover a novel treatment that targets the neurobiological mechanisms of FEP and, if successful, will be a major advance for psychiatry.

Trial registration

Australian New Zealand Clinical Trials Registry, ID: ACTRN12618000413224. Registered on 21 March 2018.

Glutathione levels and activities of glutathione metabolism enzymes in patients with schizophrenia: A systematic review and meta-analysis

BACKGROUND

Glutathione is among the important antioxidants to prevent oxidative stress. However, the relationships between abnormality in the glutathione system and pathophysiology of schizophrenia remain uncertain due to inconsistent findings on glutathione levels and/or glutathione-related enzyme activities in patients with schizophrenia.

METHODS

A systematic literature search was conducted using Embase, Medline, PsycINFO, and PubMed. Original studies, in which three metabolite levels (glutathione, glutathione disulfide, and total glutathione (glutathione+glutathione disulfide)) and five enzyme activities (glutathione peroxidase, glutathione reductase, glutamate-cysteine ligase, glutathione synthetase, and glutathione S-transferase) were measured with any techniques in both patients with schizophrenia and healthy controls, were included. Standardized mean differences were calculated to determine the group differences in the glutathione levels with a random-effects model.

RESULTS

We identified 41, 9, 15, 38, and seven studies which examined glutathione, glutathione disulfide, total glutathione, glutathione peroxidase, and glutathione reductase, respectively. Patients with schizophrenia had lower levels of both glutathione and total glutathione and decreased activity of glutathione peroxidase compared to controls. Glutathione levels were lower in unmedicated patients with schizophrenia than those in controls while glutathione levels did not differ between patients with first-episode psychosis and controls.

CONCLUSIONS

Our findings suggested that there may be glutathione deficits and abnormalities in the glutathione redox cycle in patients with schizophrenia. However, given the small number of studies examined the entire glutathione system, further studies are needed to elucidate a better understanding of disrupted glutathione function in schizophrenia, which may pave the way for the development of novel therapeutic strategies in this disorder.

Differences in the regulation of inflammatory pathways in adolescent- and adult-onset first-episode psychosis

A precise description of the inflammatory response in first-episode psychosis (FEP) by age of onset does not exist. We explored baseline and 6-month follow-up differences in the pro/anti-inflammatory balance in plasma and peripheral blood mononuclear cells in adolescent-onset FEP (≤ 18 y.o., N = 27) and adult-onset FEP (≥ 25 y.o., N = 43) using non-parametric 1-category ANCOVA, with age group as an independent variable and values of pro- and anti-inflammatory markers at baseline and at follow-up as dependent variables. We used a non-parametric repeated-measures mixed-effects model to explore the baseline/6-month change in pro- and anti-inflammatory markers within adolescent- and adult-onset groups, exploring differential trajectories of change by means of the interaction of time by age-of-onset group. Levels of the nuclear transcription factor (NFκB), a master regulator of the inflammatory and oxido/nitrosative status of cells, were higher in adolescent-onset FEP both at baseline and after 6 months. During follow-up, we found further increases in levels of soluble inflammatory markers (PGE₂ and NO₂^-) only in adolescent-onset FEP. In contrast, in adult-onset FEP, the expression of inducible NO synthase (iNOS), which is also pro-inflammatory, tended to decrease, with no further increase in other pro-inflammatory markers. Significant differences in the direction of change by age-of-onset cohort exist only for NFκB (F = 4.165, df = 2, 70.95, p = 0.019). Our results support the existence of changes in the pro/anti-inflammatory balance in FEP depending on the neurodevelopmental stage at illness onset. These results also suggest that inflammation may be a potential therapeutic target in adolescent-onset FEP.

Oxidative Stress and Inflammation in First-Episode Psychosis: A Systematic Review and Meta-analysis

Despite mixed findings, increasing evidence suggests that people with first-episode psychosis (FEP) show increased pro-inflammatory and pro-oxidative status. We used the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines to conduct a systematic literature search of cross-sectional studies comparing in vivo inflammatory and oxidative blood markers between FEP patients and healthy controls. We analyzed 61 independent samples from 59 publications, including 3002 patients with FEP (ie, patients with FEP, early psychosis, first-episode schizophrenia or early schizophrenia) and 2806 controls. After controlling for multiple comparisons, our meta-analysis showed that total antioxidant status and docosahexaenoic acid levels were significantly lower in FEP patients than in controls, whereas levels of homocysteine, interleukin-6 and tumor necrosis factor alpha were significantly higher in FEP patients than in controls. This suggests that FEP patients had reduced antioxidant status and a pro-inflammatory imbalance, and that these biological processes may be targets for managing FEP.

Associations between C-reactive protein levels and cognition during the first 6 months after acute psychosis

OBJECTIVE

Inverse relationships between the C-reactive protein (CRP) levels and cognitive performance in acute psychosis have been demonstrated. We aimed to investigate how the serum level and initial change of CRP in acutely admitted patients with psychosis was correlated with cognitive performance during a 6-months follow-up period.

METHODS

The study is part of a pragmatic, randomised trial comparing four different second-generation antipsychotic drugs, and consists of 208 acute phase patients recruited at admittance for psychosis. This study reports data for all groups collectively, and does not compare treatment groups. Measurements of CRP and cognitive performance were conducted at baseline (T1) and after 4 weeks on average after inclusion (T2). Cognition was also assessed after 3 months (T3) and 6 months (T4) of follow-up.

RESULTS

Global cognition improved during the follow-up period of 6 months, especially in the T1-T2 interval. The different cognitive subdomains showed different time-dependent profiles of improvement, with memory and attention improving significantly also in the later phases. Reduction of the CRP level during the initial follow-up interval (T1-T2) was associated with increased overall cognitive performance in the T2-T4 interval, but not in the T1-T2 interval. For the cognitive subdomains, we found an inverse association between change in CRP level and verbal abilities (T2-T4 interval), and attention (T2-T3 interval).

CONCLUSION

These findings indicate that initial changes in the serum level of CRP in the acute phase of psychosis may predict cognitive function in later phases of the disease.

Immunomodulatory effects of antipsychotic treatment on gene expression in first-episode psychosis

Previous studies suggest immunological alterations in patients with first-episode psychosis (FEP). Some studies show that antipsychotic compounds may cause immunomodulatory effects. To evaluate the immunological changes and the possible immunomodulatory effects in FEP, we recruited patients with FEP (n = 67) and matched controls (n = 38), aged 18-40 years, from the catchment area of the Helsinki University Hospital and the City of Helsinki, Finland. Fasting peripheral blood samples were collected between 8 and 10 a.m. in 10 ml PAXgene tubes. We applied the NanoString nCounter in-solution hybridization technology to determine gene expression levels of 147 candidate genes reflecting activation of the immune system. Cases had higher gene expression levels of BDKRB1 and SPP1/osteopontin compared with controls. Of the individual medications used as monotherapy, risperidone was associated with a statistically significant upregulation of 11 immune system genes, including cytokines and cytokine receptors (SPP1, IL1R1, IL1R2), pattern recognition molecules (TLR1, TLR2 and TLR6, dectin-1/CLEC7A), molecules involved in apoptosis (FAS), and some other molecules with functions in immune activation (BDKRB1, IGF1R, CR1). In conclusion, risperidone possessed strong immunomodulatory properties affecting mainly innate immune response in FEP patients, whereas the observed effects of quetiapine and olanzapine were only marginal. Our results further emphasize the importance of understanding the immunomodulatory mechanisms of antipsychotic treatment, especially in terms of specific compounds, doses and duration of medication in patients with severe mental illness. Future studies should evaluate the response pre- and post-treatment, and the possible role of this inflammatory activation for the progression of psychiatric and metabolic symptoms.

The complex association between the antioxidant defense system and clinical status in early psychosis

Oxidative stress is a pathophysiological mechanism potentially involved in psychiatric disorders. The objective of this study was to assess the relationship between total antioxidant status (TAS) and the functional status of patients with a first episode of psychosis at the onset of the disease. For this purpose, a sample of 70 patients aged between 9 and 17 years with a first episode of psychosis were followed up for a period of two years. Blood samples were drawn to measure TAS levels at three time points: at baseline, at one year, and at two years. Clinical symptoms and functioning were also assessed at the same time points using various scales. Linear regression analysis was performed to investigate the relationship between TAS and clinical status at each assessment, adjusting for potential confounding factors. The distribution of clinical variables was grouped in different percentiles to assess the dose-response in the relation between clinical variables and TAS. At baseline, patient's score on Children's Global Assessment Scale (CGAS) was directly and significantly associated with TAS with a monotonic increase in percentiles, and surprising this association was reversed after one and two years of follow-up with a monotonic decrease. In summary at the onset of the illness, TAS is positively related to clinical status, whereas as the illness progresses this correlation is reversed and becomes negative. This may be the result of an adaptive response.

White Matter Tract Integrity in Alzheimer's Disease vs. Late Onset Bipolar Disorder and Its Correlation with Systemic Inflammation and Oxidative Stress Biomarkers

Background: Late Onset Bipolar Disorder (LOBD) is the development of Bipolar Disorder (BD) at an age above 50 years old. It is often difficult to differentiate from other aging dementias, such as Alzheimer's Disease (AD), because they share cognitive and behavioral impairment symptoms.

Objectives: We look for WM tract voxel clusters showing significant differences when comparing of AD vs. LOBD, and its correlations with systemic blood plasma biomarkers (inflammatory, neurotrophic factors, and oxidative stress).

Materials: A sample of healthy controls (HC) (n = 19), AD patients (n = 35), and LOBD patients (n = 24) was recruited at the Alava University Hospital. Blood plasma samples were obtained at recruitment time and analyzed to extract the inflammatory, oxidative stress, and neurotrophic factors. Several modalities of MRI were acquired for each subject,

Methods: Fractional anisotropy (FA) coefficients are obtained from diffusion weighted imaging (DWI). Tract based spatial statistics (TBSS) finds FA skeleton clusters of WM tract voxels showing significant differences for all possible contrasts between HC, AD, and LOBD. An ANOVA F-test over all contrasts is carried out. Results of F-test are used to mask TBSS detected clusters for the AD > LOBD and LOBD > AD contrast to select the image clusters used for correlation analysis. Finally, Pearson's correlation coefficients between FA values at cluster sites and systemic blood plasma biomarker values are computed.

Results: The TBSS contrasts with by ANOVA F-test has identified strongly significant clusters in the forceps minor, inferior longitudinal fasciculus, inferior fronto-occipital fasciculus, and cingulum gyrus. The correlation analysis of these tract clusters found strong negative correlation of AD with the nerve growth factor (NGF) and brain derived neurotrophic factor (BDNF) blood biomarkers. Negative correlation of AD and positive correlation of LOBD with inflammation biomarker IL6 was also found.

Conclusion: TBSS voxel clusters tract atlas localizations are consistent with greater behavioral impairment and mood disorders in LOBD than in AD. Correlation analysis confirms that neurotrophic factors (i.e., NGF, BDNF) play a great role in AD while are absent in LOBD pathophysiology. Also, correlation results of IL1 and IL6 suggest stronger inflammatory effects in LOBD than in AD.

Oxidative Stress and Inflammation in Early Onset First Episode Psychosis: A Systematic Review and Meta-Analysis

Background

People with schizophrenia and other psychosis show increased proinflammatory and prooxidative status. However, the few studies that have specifically assessed oxidative and inflammatory markers in early onset psychosis (onset before age 18) have shown contradictory results.

Methods

Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines for systematic reviews and meta-analyses were used to conduct a systematic literature search to detect studies comparing inflammatory and oxidative markers in early onset psychosis patients and healthy controls.

Results

Seven studies met criteria for the qualitative analysis. Four studies met criteria for meta-analysis, comprising an overall sample of 261 early onset psychosis patients and 246 healthy controls. Six independent meta-analyses were performed for catalase, glutathione, glutathione peroxidase, superoxide dismutase, total antioxidant status, and cell/DNA oxidative damage. No significant differences were found between early onset psychosis patients and controls in any of the parameters assessed. Heterogeneity among studies was high. Qualitative analysis of individual studies showed an association of inflammatory and oxidative markers with clinical, cognitive, and neurobiological outcomes, especially in longitudinal assessments.

Conclusions

Despite the lack of significant differences between early onset psychosis patients and controls in the oxidative markers assessed in the meta-analyses, results based on individual studies suggest that greater inflammation and oxidative stress might lead to poorer outcomes in patients with first episodes of early onset psychosis.

Perinatal complications, lipid peroxidation, and mental health problems in a large community pediatric sample

Replicated evidence indicates that perinatal complications are associated with increased markers of oxidative stress and with mental health problems in children. However, there are fewer reports on the impact of perinatal complications in later phases of development. We aimed to investigate the estimated effects of perinatal complications on levels of lipid peroxidation and on psychopathology in children and adolescents. The study is part of the High Risk Cohort Study for Psychiatric Disorders; the population was composed by 554 students, 6-14 years of age. Serum levels of malondialdehyde, a product of lipid peroxidation, were measured by the TBARS method. A household interview with parents and caregivers was conducted and included inquiries about perinatal history, the Child Behavior Checklist (CBCL), and parent's evaluation, using the Mini International Psychiatric Interview (MINI). We created a cumulative risk index, conceptualized as each individual's cumulative exposure to perinatal complications. Results indicate that perinatal complications were associated with higher levels of TBARS. After adjusting for age, gender, socio-economic status, CBCL total problems score, parental psychopathology, and childhood maltreatment, children exposed to 3 or more perinatal complications had an 26.9% (95% CI 9.9%, 46.6%) increase in TBARS levels, relative to the unexposed group. Exploratory mediation analysis indicated that TBARS levels partially mediated the association between perinatal complications and externalizing problems. In conclusion, an adverse intrauterine and/or early life environment, as proxied by the cumulative exposure to perinatal complications, was independently associated with higher levels of lipid peroxidation in children and adolescents.

Cognitive effects of adjunctive N-acetyl cysteine in psychosis

BACKGROUND

Cognitive deficits are predictors of functional outcome in patients with psychosis. While conventional antipsychotics are relatively effective on positive symptoms, their impact on negative and cognitive symptoms is limited. Recent studies have established a link between oxidative stress and neurocognitive deficits in psychosis. N-acetylcysteine (NAC), a glutathione precursor with glutamatergic properties, has shown efficacy on negative symptoms and functioning in patients with schizophrenia and bipolar disorder, respectively. However, there are few evidence-based approaches for managing cognitive impairment in psychosis. The present study aims to examine the cognitive effects of adjunctive NAC treatment in a pooled subgroup of participants with psychosis who completed neuropsychological assessment in two trials of both schizophrenia and bipolar disorder.

METHOD

A sample of 58 participants were randomized in a double fashion to receive 2 g/day of NAC (n = 27) or placebo (n = 31) for 24 weeks. Attention, working memory and executive function domains were assessed. Differences between cognitive performance at baseline and end point were examined using Wilcoxon's test. The Mann-Whitney test was used to examine the differences between the NAC and placebo groups at the end point.

RESULTS

Participants treated with NAC had significantly higher working memory performance at week 24 compared with placebo (U = 98.5, p = 0.027).

CONCLUSIONS

NAC may have an impact on cognitive performance in psychosis, as a significant improvement in working memory was observed in the NAC-treated group compared with placebo; however, these preliminary data require replication. Glutamatergic compounds such as NAC may constitute a step towards the development of useful therapies for cognitive impairment in psychosis.

Neuroinflammation and Oxidative Stress in Psychosis and Psychosis Risk

Although our understanding of psychotic disorders has advanced substantially in the past few decades, very little has changed in the standard of care for these illnesses since the development of atypical anti-psychotics in the 1990s. Here, we integrate new insights into the pathophysiology with the increasing interest in early detection and prevention. First, we explore the role of N-methyl-d-aspartate receptors in a subpopulation of cortical parvalbumin-containing interneurons (PVIs). Postmortem and preclinical data has implicated these neurons in the positive and negative symptoms, as well as the cognitive dysfunction present in schizophrenia. These neurons also appear to be sensitive to inflammation and oxidative stress during the perinatal and peripubertal periods, which may be mediated in large part by aberrant synaptic pruning. After exploring some of the molecular mechanisms through which neuroinflammation and oxidative stress are thought to exert their effects, we highlight the progress that has been made in identifying psychosis prior to onset through the identification of individuals at clinical high risk for psychosis (CHR). By combining our understanding of psychosis pathogenesis with the increasing characterization of endophenotypes that precede frank psychosis, it may be possible to identify patients before they present with psychosis and intervene to reduce the burden of the disease to both patients and families.

Inflammation, Stress Response, and Redox Dysregulation Biomarkers: Clinical Outcomes and Pharmacological Implications for Psychosis

In recent years, several studies claiming the finding of a specific biomarker for the identification of the "high-risk state" to develop psychosis, first psychotic episode, as well as the prediction of the individual response to antipsychotics have been published. Together with genetic reports, numerous publications in this field have been focused on inflammation and stress response blood biomarkers, as well as on indicators of redox dysregulation. In this review, we focus on human studies found in PubMed from January 1^st 2010 to January 31^st 2017, describing the clinical use of these biomarkers to detect the "premorbid" psychotic state and early phases of the disease. Their pharmacological implications in predicting and monitoring the individual response to antipsychotic medication is also discussed.

Level of serum thioredoxin and correlation with neurocognitive functions in patients with schizophrenia using clozapine and other atypical antipsychotics

Thioredoxin is a serum antioxidant that has been investigated in the etiology of schizophrenia. The aim of this study is investigating the relationship between serum thioredoxin levels and cognitive functions in acute psychotic episode and remission state patients with schizophrenia; and examining whether there were differences between patients using clozapine and other atypical antipsychotics; including risperidone, olanzapine and amisulpride. This research was performed in schizophrenia patients hospitalized with acute psychotic episode (n=57), reevaluated patients after the initiation of treatment (mean 16 weeks) (n=46), and healthy controls (n=41). Positive and Negative Syndrome Scale, Clinic Global Impressions Scale, Neuropsychologic test battery to assess cognitive performance, and serum thioredoxin levels measured by ELISA were used in this research. Serum thioredoxin levels were highest in acute psychotic episode, lower in the remission state and the lowest in healthy controls. Significant correlation has been established between serum thioredoxin levels and Trail Making Test-A performance in remission state patients. In conclusion, serum thioredoxin levels were increased in acute psychotic episode and decreased in remission state, and its relationship with attention is worth to consider in schizophrenia patients.

Oxidative Stress and DNA Damage in Untreated First-Episode Psychosis in Adolescents

OBJECTIVE

Oxidative stress has been reported to play a role in the psychopathology of schizophrenia, though only a few studies have investigated the relationship between early-onset schizophrenia and oxidative stress. The aim of the present study is to evaluate the level of oxidative stress and the presence of DNA damage in first-episode psychosis (FEP) in adolescents.

METHODS

This study was conducted in the Department of Child Psychiatry of the Dicle University Hospital. It included 20 adolescent patients (age 11-17 years) with psychosis (acute psychosis, schizophreniform disorder, or schizophrenia) according to DSM-IV criteria who had received no previous psychiatric therapy (patient group) and 20 age/gender-matched healthy adolescents (control group). Structured psychiatric interviews [Kiddie Schedule for Affective Disorders and Schizophrenia, Present and Lifetime Version (K-SADS-PL) and Positive and Negative Symptom Scale (PANSS)] were conducted on the patients, and the Clinical Global Impressions (CGI) scale was used to evaluate the severity of disease. Glutathione peroxidase (GPx), superoxide dismutase (SOD), coenzyme Q (CoQ), and 8-hydroxy-2-deoxyguanosine (8-OHdG) levels were determined using the ELISA method and commercial ELISA kits.

RESULTS

The mean age was 14.5 ± 1.6 years in the FEP group (male-to-female ratio: 8/12) and 14.4 ± 1.5 years in the control group (male-to-female ratio: 8/12). There were no differences between the patient and control groups in terms of SOD, GPx, or 8-OHdG values (p > 0.05).

CONCLUSIONS

This study on DNA damage and oxidative stress in FEP in adolescents had a small sample size, and our data suggest that oxidative stress is associated with a chronic disease course rather than being an early sign of early-onset schizophrenia.

Reduced endogenous urinary total antioxidant power and its relation of plasma antioxidant activity of superoxide dismutase in individuals with autism spectrum disorder

Individuals with autism spectrum disorders (ASD) have impaired detoxification capacity. Investigating　the neurobiological bases of　impaired antioxidant capacity is thus a research priority in the pathophysiology of ASD.　We measured　the urinary levels of hexanoyl-lysine (HEL) which is a new oxidative stress　biomarker, total antioxidant power (TAP) and DNA methylation biomarker 8-hydroxy-2'-deoxyguanosine (8-OHdG), and the plasma levels of superoxide dismutase (SOD), which is a major antioxidant enzyme. We examined whether the urinary levels of these enzymes and biomarkers may be related to symptoms of social impairment in 20 individuals with ASD (meanage,11.1±5.2years) and 12 age- and gender-matched healthy controls (meanage,14.3±6.2years). Symptoms of social impairment were　assessed using the Social Responsiveness Scale (SRS). The dietary TAP of the fruit juice, chocolate, cookies, biscuits, jam and marmalade were significantly higher in the ASD group than in the control group, although the intake of nutrients was not significantly different between the groups. The urinary TAP levels were significantly lower in the ASD group than in the control group. There were no significantly differences in urinary HEL and 8-OHdG levels between the ASD and control groups. The SRS scores were significantly higher in the ASD group than in the control group. Stepwise regression analysis revealed that urinary TAP levels and plasma SOD levels can differences in the biomarkers and the SRS scores between the ASD group and the control group. The endogenous antioxidant capacity may be deficient without altered urinary HEL and 8-OHdG levels in individuals with ASD. The plasma SOD levels may be related to reduced endogenous antioxidant capacity.

Cognition and psychopathology in first-episode psychosis: are they related to inflammation?

BACKGROUND

Cognitive deficits are present from the onset of psychosis and are considered a core feature of the disorder. Increasing evidence suggests that cognitive function is associated with inflammatory processes. This study evaluated the association between cognition and inflammatory biomarkers in first-episode psychosis (FEP), in order to identify cognitive phenotypes from inflammatory expression profiles.

METHOD

A case-control study of 92 FEP patients and 80 matched controls was used. Neurocognitive assessment, including verbal ability, sustained attention, verbal memory, working memory and executive function, was performed. The expression of pro- and anti-inflammatory mediators of the main intracellular inflammatory pathway was measured in peripheral blood mononuclear cells and plasma.

RESULTS

FEP patients performed worse in all cognitive domains compared to controls and had higher expression of pro-inflammatory mediators and lower expression of anti-inflammatory mediators. In the FEP group, cognition and psychopathology were associated with inflammation. Hierarchical regression analysis showed that association between the anti-inflammatory prostaglandin 15d-PGJ2 and sustained attention on one hand, and COX-2 expression and executive function on the other, were statistically significant.

CONCLUSIONS

Our study provides evidence for an association between anti-inflammatory biomarkers and cognition in FEP. The identification of a subgroup of patients based on these measures could be useful to guide treatment programmes by providing tools to select a personalized treatment approach, but longitudinal studies are needed before. In the future, establishment of biomarkers linked to cognition would be useful to monitor the course of cognitive impairment, but substantially more data will be required. Determination of IκBα, the inhibitory protein of the pro-inflammatory transcription factor NFκB, could be useful in early phases to assess clinical severity.

Discrimination between Alzheimer's Disease and Late Onset Bipolar Disorder Using Multivariate Analysis

Background

Late onset bipolar disorder (LOBD) is often difficult to distinguish from degenerative dementias, such as Alzheimer disease (AD), due to comorbidities and common cognitive symptoms. Moreover, LOBD prevalence in the elder population is not negligible and it is increasing. Both pathologies share pathophysiological neuroinflammation features. Improvements in differential diagnosis of LOBD and AD will help to select the best personalized treatment.

Objective

The aim of this study is to assess the relative significance of clinical observations, neuropsychological tests, and specific blood plasma biomarkers (inflammatory and neurotrophic), separately and combined, in the differential diagnosis of LOBD versus AD. It was carried out evaluating the accuracy achieved by classification-based computer-aided diagnosis (CAD) systems based on these variables.

Materials

A sample of healthy controls (HC) (n = 26), AD patients (n = 37), and LOBD patients (n = 32) was recruited at the Alava University Hospital. Clinical observations, neuropsychological tests, and plasma biomarkers were measured at recruitment time.

Methods

We applied multivariate machine learning classification methods to discriminate subjects from HC, AD, and LOBD populations in the study. We analyzed, for each classification contrast, feature sets combining clinical observations, neuropsychological measures, and biological markers, including inflammation biomarkers. Furthermore, we analyzed reduced feature sets containing variables with significative differences determined by a Welch’s t-test. Furthermore, a battery of classifier architectures were applied, encompassing linear and non-linear Support Vector Machines (SVM), Random Forests (RF), Classification and regression trees (CART), and their performance was evaluated in a leave-one-out (LOO) cross-validation scheme. Post hoc analysis of Gini index in CART classifiers provided a measure of each variable importance.

Results

Welch’s t-test found one biomarker (Malondialdehyde) with significative differences (p < 0.001) in LOBD vs. AD contrast. Classification results with the best features are as follows: discrimination of HC vs. AD patients reaches accuracy 97.21% and AUC 98.17%. Discrimination of LOBD vs. AD patients reaches accuracy 90.26% and AUC 89.57%. Discrimination of HC vs LOBD patients achieves accuracy 95.76% and AUC 88.46%.

Conclusion

It is feasible to build CAD systems for differential diagnosis of LOBD and AD on the basis of a reduced set of clinical variables. Clinical observations provide the greatest discrimination. Neuropsychological tests are improved by the addition of biomarkers, and both contribute significantly to improve the overall predictive performance.

First-episode psychosis is associated with oxidative stress: Effects of short-term antipsychotic treatment

AIMS

In the present study, our aim was to investigate the oxidative-antioxidative systems in unmedicated first-episode psychosis (FEP) patients at the beginning and after short-term treatment.

METHODS

This study consisted of 29 patients who experienced an FEP and 25 control subjects. In order to investigate the oxidative status, we determined plasma malondialdehyde (MDA) levels, oxidizability of red blood cells, oxidation and oxidizability of apolipoprotein B-containing lipoproteins (apo B-basal MDA and apo B-ΔMDA). In order to evaluate the antioxidative defense, we measured serum total antioxidative capacity, uric acid, albumin, total bilirubin and vitamin E levels and serum paraoxonase/arylesterase, whole blood glutathione peroxidase (GPx) and red blood cell superoxide dismutase activities before and after 6 weeks of treatment in patients with FEP.

RESULTS

Plasma MDA and apo B-basal MDA levels and red blood cell superoxide dismutase activity were significantly higher and serum arylesterase and whole blood-GPx activities were lower in the FEP group than those of the healthy control group. There were not any significant changes in the oxidative and antioxidative system parameters (except increased vitamin E levels) after treatment.

CONCLUSIONS

The results of this study suggest that FEP is accompanied by oxidative stress. However, further studies are needed to clarify the role of oxidative stress in the physiopathologic mechanisms of FEP, so that oxidative and antioxidative system parameters can be used in the management of these patients. In accordance with psychiatric evaluation, for a better management, patients with FEP may require a multidisciplinary approach, including oxidative and antioxidative system parameters.

The promise of biological markers for treatment response in first-episode psychosis: a systematic review

Successful treatment of first-episode psychosis is one of the major factors that impacts long-term prognosis. Currently, there are no satisfactory biological markers (biomarkers) to predict which patients with a first-episode psychosis will respond to which treatment. In addition, a non-negligible rate of patients does not respond to any treatment or may develop side effects that affect adherence to the treatments as well as negatively impact physical health. Thus, there clearly is a pressing need for defining biomarkers that may be helpful to predict response to treatment and sensitivity to side effects in first-episode psychosis. The present systematic review provides (1) trials that assessed biological markers associated with antipsychotic response or side effects in first-episode psychosis and (2) potential biomarkers associated with biological disturbances that may guide the choice of conventional treatments or the prescription of innovative treatments. Trials including first-episode psychoses are few in number. Most of the available data focused on pharmacogenetics markers with so far only preliminary results. To date, these studies yielded-beside markers for metabolism of antipsychotics-no or only a few biomarkers for response or side effects, none of which have been implemented in daily clinical practice. Other biomarkers exploring immunoinflammatory, oxidative, and hormonal disturbances emerged as biomarkers of first-episode psychoses in the last decades, and some of them have been associated with treatment response. In addition to pharmacogenetics, further efforts should focus on the association of emergent biomarkers with conventional treatments or with innovative therapies efficacy, where some preliminary data suggest promising results.

Predictors of outcome in early-onset psychosis: a systematic review

Given the global burden of psychotic disorders, the identification of patients with early-onset psychosis (EOP; that is, onset before the age of 18) at higher risk of adverse outcome should be a priority. A systematic search of Pubmed, Embase, and PsycInfo (1980 through August 2014) was performed to identify longitudinal observational studies assessing correlates and/or predictors of clinical, functional, cognitive, and biological outcomes in EOP. Seventy-five studies were included in the review. Using multivariate models, the most replicated predictors of worse clinical, functional, cognitive, and biological outcomes in EOP were premorbid difficulties and symptom severity (especially of negative symptoms) at baseline. Longer duration of untreated psychosis (DUP) predicted worse clinical, functional, and cognitive outcomes. Higher risk of attempting suicide was predicted by greater severity of psychotic illness and of depressive symptoms at the first episode of psychosis. Age at onset and sex were not found to be relevant predictors of outcome in most multivariate models, whereas studies using bivariate analyses yielded inconsistent results. Lower intelligence quotient at baseline predicted lower insight at follow-up, worse functional outcomes, and a diagnostic outcome of schizophrenia. Biological predictors of outcome in EOP have been little studied and have not been replicated. Lower levels of antioxidants at baseline predicted greater brain volume changes and worse cognitive functioning at follow-up, whereas neuroimaging markers such as regional cortical thickness and gray matter volume at baseline predicted remission and better insight at follow-up, respectively. EOP patients with poorer premorbid adjustment and prominent negative symptoms at initial presentation are at risk of poor outcome. They should therefore be the target of careful monitoring and more intensive interventions to address whether the disease course can be modified in this especially severely affected group. Early intervention strategies to reduce DUP may also improve outcome in EOP.