Inflammatory DEpression Advances in Schizophrenia (IDEAS): A precision medicine approach of the national FACE-SZ cohort

Toxoplasma gondii, Herpesviridae and long-term risk of transition to first-episode psychosis in an ultra high-risk sample

BACKGROUND

Ultra high-risk (UHR) criteria were introduced to identify people at imminent risk of developing psychosis. To improve prognostic accuracy, additional clinical and biological risk factors have been researched. Associations between psychotic disorders and infections with Toxoplasma gondii and Herpesviridae have been found. It is unknown if exposure to those pathogens increases the risk of transition to psychosis in UHR cohorts.

METHODS

We conducted a long-term follow-up of 96 people meeting UHR criteria, previously seen at the Personal Assessment and Crisis Evaluation (PACE) clinic, a specialized service in Melbourne, Australia. Transition to psychosis was assessed using the Comprehensive Assessment of the At-Risk Mental State (CAARMS) and state public mental health records. The relationship between IgG antibodies to Herpesviridae (HSV-1, HSV-2, CMV, EBV, VZV) and Toxoplasma gondii and risk for transition was examined with Cox regression models.

RESULTS

Mean follow-up duration was 6.46 (±3.65) years. Participants who transitioned to psychosis (n = 14) had significantly higher antibody titers for Toxoplasma gondii compared to those who did not develop psychosis (p = 0.03). After adjusting for age, gender and year of baseline assessment, seropositivity for Toxoplasma gondii was associated with a 3.6-fold increase in transition hazard in multivariate Cox regression models (HR = 3.6; p = 0.036). No significant association was found between serostatus for Herpesviridae and risk of transition.

CONCLUSIONS

Exposure to Toxoplasma gondii may contribute to the manifestation of positive psychotic symptoms and increase the risk of transitioning to psychosis in UHR individuals.

The gut-brain axis in irritable bowel syndrome and inflammatory bowel disease

Research increasingly demonstrates the bidirectional communication between gut microbiota and the brain, enhancing the role of gut microbiota modulation in the treatment of central nervous system (CNS) disorders. The first five years of life are extremely important as it affects the development of gut microbiota, immune system and, consequently, the onset of psychometric alterations, particularly in genetically predisposed individuals. In this review, we focus on the link between specific microbial genera, gastrointestinal (GI) disorders, anxiety and depression and on the effects of different therapeutic strategies for mood disorders on gut microbiota.

A transnosographic approach of negative symptoms pathophysiology in schizophrenia and depressive disorders

BACKGROUND

Negative Symptoms (blunted affect, alogia, anhedonia, avolition and asociality) are observed in schizophrenia but also in depressive disorders.

OBJECTIVE

To gather cognitive, neuroanatomical, neurofunctional and neurobiological knowledge of negative symptoms in studies on schizophrenia, depressive disorder, and transnosographic studies.

RESULTS

Blunted affect in schizophrenia is characterized by amygdala hyperactivation and frontal hypoactivation, also found in depressive disorder. Mirror neurons, may be related to blunted affect in schizophrenia. Alogia may be related to cognitive dysfunction and basal ganglia area impairments in schizophrenia. Data surrounding alogia in depressive disorder is scarce; wider speech deficits are often studied instead. Consummatory Anhedonia may be less affected than Anticipatory Anhedonia in schizophrenia. Anhedonia is associated with reward impairments and altered striatal functions in both diagnostics. Amotivation is associated with Corticostriatal Hypoactivation in both disorders. Anhedonia and amotivation are transnosographically associated with dopamine dysregulation. Asociality may be related to oxytocin.

CONCLUSION

Pathophysiological hypotheses are specific to each dimension of negative symptoms and overlap across diagnostic boundaries, possibly underpinning the observed clinical continuum.

Sexual dysfunctions in schizophrenia: Beyond antipsychotics. A systematic review

BACKGROUND

Sexual dysfunctions (SD) in schizophrenia are frequent with strong impact on adherence and quality of life. Current recommendations stipulate to switch to prolactin-sparing antipsychotic in case of SD.

OBJECTIVES

To synthetize in a systematic review data on the SD prevalence and the associated risk factors in schizophrenia (SZ).

METHODS

Medline, Google Scholar, PsychInfo, and Cochrane were explored, without any year or language restriction.

RESULTS

Overall, 89 studies and 25,490 participants were included in the present review. SZ subjects aged 18-70 reported high SD frequency [30%-82%] (men [33%- 85%]; women [25%- 85%]). For SZ men erectile dysfunction [31%-95%] was the most frequent SD vs. loss of libido for women [31%-100%]. The following risk factors were associated with increased SD: 1. Illness severity (including psychotic symptomatology, early age at SZ onset, negative symptomatology, and continuous illness course), 2. Depressive symptomatology 3. Antipsychotics (especially first generation antipsychotics, risperidone and antipsychotic polytherapy). Switching to prolactin-sparing antipsychotics has shown effectiveness in some studies (especially aripiprazole). Antidepressants were not found to be associated with SD in SZ subjects.

CONCLUSION

The prevalence of SD is high in SZ subjects. In addition to the current guidelines, the present review suggests that treating depressive symptoms may be a major intervention to improve SD in SZ subjects. Sociodemographic variables, physical illnesses, metabolic syndrome and peripheral inflammation have been poorly or never explored and should be included in future studies.