Long-term diagnostic stability, predictors of diagnostic change, and time until diagnostic change of first-episode psychosis: a 21-year follow-up study

BACKGROUND

Although diagnostic instability in first-episode psychosis (FEP) is of major concern, little is known about its determinants. This very long-term follow-up study aimed to examine the diagnostic stability of FEP diagnoses, the baseline predictors of diagnostic change and the timing of diagnostic change.

METHODS

This was a longitudinal and naturalistic study of 243 subjects with FEP who were assessed at baseline and reassessed after a mean follow-up of 21 years. The diagnostic stability of DSM-5 psychotic disorders was examined using prospective and retrospective consistencies, logistic regression was used to establish the predictors of diagnostic change, and survival analysis was used to compare time to diagnostic change across diagnostic categories.

RESULTS

The overall diagnostic stability was 47.7%. Schizophrenia and bipolar disorder were the most stable diagnoses, with other categories having low stability. Predictors of diagnostic change to schizophrenia included a family history of schizophrenia, obstetric complications, developmental delay, poor premorbid functioning in several domains, long duration of untreated continuous psychosis, spontaneous dyskinesia, lack of psychosocial stressors, longer duration of index admission, and poor early treatment response. Most of these variables also predicted diagnostic change to bipolar disorder but in the opposite direction and with lesser effect sizes. There were no significant differences between specific diagnoses regarding time to diagnostic change. At 10-year follow-up, around 80% of the diagnoses had changed.

CONCLUSIONS

FEP diagnoses other than schizophrenia or bipolar disorder should be considered as provisional. Considering baseline predictors of diagnostic change may help to enhance diagnostic accuracy and guide therapeutic interventions.

Living with schizophrenia and type 2 diabetes and the implication for diabetes self-care: A qualitative study

AIM

To achieve an in-depth understanding of the challenges associated with diabetes management when having both schizophrenia and type 2 diabetes, while also identifying the needs for improved diabetes self-care.

DESIGN

The study employed a qualitative explorative design utilizing a phenomenological-hermeneutic inspired approach, involving field observations and individual semistructured interviews.

METHODS

Data were collected during 2020-2021 through 17 field observations of outpatient consultations and 13 individual semistructured interviews. Data, including field notes and verbatim transcribed interviews, underwent analysis following Ricoeur's interpretive philosophy, encompassing three levels: naïve reading, structural analysis and critical interpretation and discussion. This study adheres to the COREQ guidelines for qualitative research.

RESULTS

Three key themes emerged: 'Diabetes when life is noisy', 'Sacrifices and compromises in life' and 'The double silence'. Everyday life is significantly affected when having both schizophrenia and T2D. The mental health state dominates in relation to diabetes self-care and individuals experience challenges balancing between the two conditions. However, there exists a general acknowledgement for diabetes and its long-term complications as a serious medical condition demanding careful attention and treatment.

CONCLUSION

Self-managing two such complex conditions can be overwhelming and make it difficult for the individual to differentiate symptoms and prioritize diabetes care. Moreover, the existing fragmentation within healthcare systems poses communication challenges, resulting in disjointed patient pathways.

IMPLICATIONS FOR PATIENT CARE

The study emphasizes the need for a holistic re that addresses the physical, emotional and social challenges. There is also a need for increased awareness and education among informal caregivers and healthcare professionals to foster better understanding and support.

Reward anticipation-related neural activation following cued reinforcement in adults with psychotic psychopathology and biological relatives

BACKGROUND

Schizophrenia is associated with hypoactivation of reward sensitive brain areas during reward anticipation. However, it is unclear whether these neural functions are similarly impaired in other disorders with psychotic symptomatology or individuals with genetic liability for psychosis. If abnormalities in reward sensitive brain areas are shared across individuals with psychotic psychopathology and people with heightened genetic liability for psychosis, there may be a common neural basis for symptoms of diminished pleasure and motivation.

METHODS

We compared performance and neural activity in 123 people with a history of psychosis (PwP), 81 of their first-degree biological relatives, and 49 controls during a modified Monetary Incentive Delay task during fMRI.

RESULTS

PwP exhibited hypoactivation of the striatum and anterior insula (AI) during cueing of potential future rewards with each diagnostic group showing hypoactivations during reward anticipation compared to controls. Despite normative task performance, relatives demonstrated caudate activation intermediate between controls and PwP, nucleus accumbens activation more similar to PwP than controls, but putamen activation on par with controls. Across diagnostic groups of PwP there was less functional connectivity between bilateral caudate and several regions of the salience network (medial frontal gyrus, anterior cingulate, AI) during reward anticipation.

CONCLUSIONS

Findings implicate less activation and connectivity in reward processing brain regions across a spectrum of disorders involving psychotic psychopathology. Specifically, aberrations in striatal and insular activity during reward anticipation seen in schizophrenia are partially shared with other forms of psychotic psychopathology and associated with genetic liability for psychosis.

Transcranial Alternating Current Stimulation Alters Auditory Steady-State Oscillatory Rhythms and Their Cross-Frequency Couplings

Auditory cortical plasticity deficits in schizophrenia are evidenced with electroencephalographic (EEG)-derived biomarkers, including the 40-Hz auditory steady-state response (ASSR). Aiming to understand the underlying oscillatory mechanisms contributing to the 40-Hz ASSR, we examined its response to transcranial alternating current stimulation (tACS) applied bilaterally to the temporal lobe of 23 healthy participants. Although not responding to gamma tACS, the 40-Hz ASSR was modulated by theta tACS (vs sham tACS), with reductions in gamma power and phase locking being accompanied by increases in theta-gamma phase-amplitude cross-frequency coupling. Results reveal that oscillatory changes induced by frequency-tuned tACS may be one approach for targeting and modulating auditory plasticity in normal and diseased brains.

Evidence-based psychosocial interventions in schizophrenia: a critical review

PURPOSE OF REVIEW

Schizophrenia Spectrum Disorders (SSD) are severe conditions that frequently produce significant impairment in cognitive performance, social skills and psychosocial functioning. As pharmacological treatment alone often provides only limited improvements on these outcomes, several psychosocial interventions are employed in psychiatric rehabilitation practice to improve of real-world outcomes of people living with SSD: the present review aims to provide a critical overview of these treatments, focusing on those that show consistent evidence of effectiveness.

RECENT FINDINGS

Several recent systematic reviews and meta-analyses have investigated in detail the acceptability, the effectiveness on several specific outcomes and moderators of response of different psychosocial interventions, and several individual studies have provided novel insight on their implementation and combination in rehabilitation practice.

SUMMARY

Cognitive remediation, metacognitive training, social skills training, psychoeducation, family interventions, cognitive behavioral therapy, physical exercise and lifestyle interventions, supported employment and some other interventions can be fully considered as evidence-based treatments in SSD. Psychosocial interventions could be of particular usefulness in the context of early intervention services. Future research should focus on developing newer interventions, on better understanding the barriers and the facilitators of their implementation in clinical practice, and exploring the opportunities provided by novel technologies.

The association between schizophrenia and increased COVID-19 mortality in a cohort of over 2 million people in Brazil

OBJECTIVE

To describe the clinical outcomes and risk factors of death related to mental disorders in a cohort of Brazilian hospitalized patients with COVID-19.

METHODS

This retrospective cohort study utilized the Brazilian database SIVEP-Gripe to analyze patients aged ≥18 years who had been hospitalized with COVID-19 between 2020 and 2022. The exposure of interest were mental disorders (anxiety, depression, schizophrenia, and bipolar disorder), identified through self-reported fields. The primary outcome was in-hospital mortality. Covariates included demographic and clinical features. Descriptive statistics, t-tests, chi-square tests, and binary logistic regression were used to analyze the data.

RESULTS

A cohort of 2,124,285 patients was included in the analysis, with 23,246 individuals (1.1%) having self-reported mental disorders. Among these mental disorders, depression was the most prevalent (52.3%). The mortality rate of the patients with mental disorders was 30.8%. Analysis of risk factors for mortality revealed that age, gender, region, dyspnea, low oxygen saturation, and comorbidities were associated with an increased risk of death. Patients with schizophrenia had a higher mortality risk (aOR:1.68;95%CI:1.54-1.81).

CONCLUSIONS

Patients diagnosed with schizophrenia have a greater likelihood of COVID-19- related death than those without mental health conditions. These findings underscore the significant effect of serious mental disorders on COVID-19 mortality.

Barriers to long-acting injectable atypical antipsychotic use in Japan: Insights from a comparative psychiatrist survey

AIMS

To investigate the negative attitudes of Japanese psychiatrists toward atypical long-acting injectable (LAI) antipsychotics, which are the current mainstream LAIs in Japan.

METHODS

We surveyed 69 Japanese psychiatrists using a 5-point Likert scale to assess their attitudes toward atypical LAI antipsychotics. Our assessment referenced concerns identified in a study conducted in Japan a decade ago, which found significant differences when compared with a survey of German psychiatrists. We also identified the factors influencing these negative attitudes. Additionally, the results were compared with those of previous Japanese and German studies.

RESULTS

More than 50% of Japanese psychiatrists expressed negative attitudes toward atypical LAI antipsychotics in various areas. These concerns included apprehensions about cost, reluctance to recommend them initially, pain from injections, complexity of switching to LAI, usage in first-episode cases, and sufficient medication adherence with oral drugs. In all three studies, cost and adequate adherence to oral medication were concerns that exceeded the average of the three negative comments. Age and experience in psychiatry influenced the psychiatrists' attitudes toward using these drugs in first-episode cases.

CONCLUSIONS

These findings shed light on the reasons for the underutilization of atypical LAI antipsychotics and suggest opportunities to enhance their appropriate use in clinical settings.

Traumatic Brain Injury and Risk of Schizophrenia and Other Non-mood Psychotic Disorders: Findings From a Large Inpatient Database in the United States

BACKGROUND

Traumatic brain injury (TBI) is linked with an increased risk of schizophrenia and other non-mood psychotic disorders (psychotic disorders), but the prevalence and contributing factors of these psychiatric conditions post-TBI remain unclear. This study explores this link to identify key risk factors in TBI patients.

METHODS

We used the 2017 National Inpatient Sample dataset. Patients with a history of TBI (n = 26 187) were identified and matched 1:1 by age and gender to controls without TBI (n = 26 187). We compared clinical and demographic characteristics between groups. The association between TBI and psychotic disorders was explored using the logistic regression analysis, and results were presented as Odds ratio (OR) and 95% confidence interval (CI).

RESULTS

Psychotic disorders were significantly more prevalent in TBI patients (10.9%) vs controls (4.7%) (P < .001). Adjusted odds of psychotic disorders were 2.2 times higher for TBI patients (95% CI 2.05-2.43, P < .001). Male TBI patients had higher psychotic disorders prevalence than females (11.9% vs 8.4%). Younger age, bipolar disorder, anxiety disorders, substance abuse, personality disorders, and intellectual disability are associated with an increased risk of psychotic disorders in men.

CONCLUSION

Our study found that hospitalized TBI patients had 2.2 times higher odds of Schizophrenia non-mood psychotic disorder, indicating an association. This highlights the need for early screening of psychotic disorders and intervention in TBI patients, calling for more research.

Postnatal hypofunction of N-methyl-D-aspartate receptors alters perforant path synaptic plasticity and filtering and impairs dentate gyrus-mediated spatial discrimination

BACKGROUND AND PURPOSE

Transient hypofunction of the NMDA receptor represents a convergence point for the onset and further development of psychiatric disorders, including schizophrenia. Although the cumulative evidence indicates dysregulation of the hippocampal formation in schizophrenia, the integrity of the synaptic transmission and plasticity conveyed by the somatosensorial inputs to the dentate gyrus, the perforant pathway synapses, have barely been explored in this pathological condition.

EXPERIMENTAL APPROACH

We identified a series of synaptic alterations of the lateral and medial perforant paths in animals postnatally treated with the NMDA antagonist MK-801. This dysregulation suggests decreased cognitive performance, for which the dentate gyrus is critical.

KEY RESULTS

We identified alterations in the synaptic properties of the lateral and medial perforant paths to the dentate gyrus synapses in slices from MK-801-treated animals. Altered glutamate release and decreased synaptic strength precede an impairment in the induction and expression of long-term potentiation (LTP) and CB1 receptor-mediated long-term depression (LTD). Remarkably, by inhibiting the degradation of 2-arachidonoylglycerol (2-AG), an endogenous ligand of the CB1 receptor, we restored the LTD in animals treated with MK-801. Additionally, we showed for the first time, that spatial discrimination, a cognitive task that requires dentate gyrus integrity, is impaired in animals exposed to transient hypofunction of NMDA receptors.

CONCLUSION AND IMPLICATIONS

Dysregulation of glutamatergic transmission and synaptic plasticity from the entorhinal cortex to the dentate gyrus has been demonstrated, which may explain the cellular dysregulations underlying the altered cognitive processing in the dentate gyrus associated with schizophrenia.

Liraglutide 3.0 mg once daily for the treatment of overweight and obesity in patients hospitalised at a forensic psychiatric department: A 26-week open-label feasibility study

INTRODUCTION

Overweight and obesity constitute a major concern among patients treated at forensic psychiatric departments. The present clinical feasibility study aimed at investigating the extent to which glucagon-like peptide 1 receptor agonist (GLP-1RA) treatment with once-daily liraglutide 3.0 mg could be a feasible pharmacological treatment of these conditions in patients with schizophrenia spectrum disorders hospitalised in forensic psychiatry.

METHODS

The 26-week, open-label feasibility study included participants aged 18-65 years diagnosed with a severe mental illness and hospitalised at a forensic psychiatric department. At the time of inclusion, all participants fulfilled the indication for using liraglutide as a treatment for overweight and obesity. Participants' baseline examinations were followed by a 26-week treatment period with liraglutide injection once daily according to a fixed uptitration schedule of liraglutide, with a target dose of 3.0 mg. Each participant attended seven visits to evaluate the efficacy and adverse events. The primary endpoint was the number of "completers", with adherence defined as >80% injections obtained in the period, weeks 12-26. Determining whether liraglutide is a feasible treatment was pre-defined to a minimum of 75% completers.

RESULTS

Twenty-four participants were included in the study. Sex, male = 19 (79.2%). Mean age: 42.3 [25th and 75th percentiles: 39.1; 48.4] years; body mass index (BMI): 35.7 [31.7; 37.5] kg/m2; glycated haemoglobin (HbA1c): 37 [35; 39] mmol/mol. Eleven out of 24 participants (46%) completed the study. For the completers, the median net body weight loss after 26 weeks of participation was -11.4 kg [-15.4; -5.9]. The net difference in HbA1C and BMI was -2.0 mmol/mol [-4; -1] and -3.6 kg/m2 [-4.7; -1.8], respectively. The weight change and reduction in HbA1c and BMI were all statistically significant from baseline.

CONCLUSION

The study did not confirm our hypothesis that liraglutide is a feasible treatment for a minimum of 75% of the patients initiating treatment with liraglutide while hospitalised in a forensic psychiatric department. The high dropout rate may be due to the non-naturalistic setting of the clinical trial. For the proportion of patients compliant with the medication, liraglutide 3.0 mg was an efficient treatment for overweight.

Association of cytokines levels, psychopathology and cognition among CR-TRS patients with metabolic syndrome

Clozapine-resistant treatment-refractory schizophrenia (CR-TRS) patients face significant clinical challenges. While links between metabolic syndrome (MetS) and inflammatory cytokines in schizophrenia have been established, the relationship between MetS and cytokine levels in CR-TRS patients remains unexplored. This study aimed to investigate the relationship between cytokines levels, clinical symptoms and cognitive impairments in CR-TRS patients, both with and without MetS. The study included 69 CR-TRS patients (31with MetS and 38 without MetS) and 84 healthy controls. The levels of IL-2, IL-6, TNF-α and routine biochemical parameters were measured. Psychopathological symptoms and cognitive function were assessed using the Positive and Negative Syndrome Scale (PANSS) and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS), respectively. We found that CR-TRS patients with MetS displayed lower cognitive function scores compared to those without MetS, even when accounting for potential confounders. TNF-α levels were significantly higher in CRTRS patients with MetS compared to those without MetS, demonstrating substantial pathophysiological potential for CR-TRS patients with MetS via receiver operating characteristic curve (ROC). In CR-TRS patients without MetS, IL-2 independently contributed to the total score and general psychopathology subscore of PANSS. Additionally, IL-6 exhibited an independent contribution to the positive subscore of PANSS. In terms of cognition function, IL-6 independently contributed to the delayed memory of RBANS in CR-TRS patients without MetS. TNF-α could potentially serve as a predictive marker for distinguishing between CR-TRS patients with/without MetS, while IL-2 and IL-6 could independently contribute to psychopathological symptoms or cognitive function in CRTRS patients without MetS. Our study provided insights into the potential interplay between cytokines, clinical symptoms and cognitive impairments in CR-TRS patients with/without MetS.

Shared Genetic Determinants of Schizophrenia and Autism Spectrum Disorder Implicate Opposite Risk Patterns: A Genome-Wide Analysis of Common Variants

BACKGROUND AND HYPOTHESIS

The synaptic pruning hypothesis posits that schizophrenia (SCZ) and autism spectrum disorder (ASD) may represent opposite ends of neurodevelopmental disorders: individuals with ASD exhibit an overabundance of synapses and connections while SCZ was characterized by excessive pruning of synapses and a reduction. Given the strong genetic predisposition of both disorders, we propose a shared genetic component, with certain loci having differential regulatory impacts.

STUDY DESIGN

Genome-Wide single nucleotide polymorphism (SNP) data of European descent from SCZ (N cases = 53 386, N controls = 77 258) and ASD (N cases = 18 381, N controls = 27 969) were analyzed. We used genetic correlation, bivariate causal mixture model, conditional false discovery rate method, colocalization, Transcriptome-Wide Association Study (TWAS), and Phenome-Wide Association Study (PheWAS) to investigate the genetic overlap and gene expression pattern.

STUDY RESULTS

We found a positive genetic correlation between SCZ and ASD (rg = .26, SE = 0.01, P = 7.87e-14), with 11 genomic loci jointly influencing both conditions (conjFDR <0.05). Functional analysis highlights a significant enrichment of shared genes during early to mid-fetal developmental stages. A notable genetic region on chromosome 17q21.31 (lead SNP rs2696609) showed strong evidence of colocalization (PP.H4.abf = 0.85). This SNP rs2696609 is linked to many imaging-derived brain phenotypes. TWAS indicated opposing gene expression patterns (primarily pseudogenes and long noncoding RNAs [lncRNAs]) for ASD and SCZ in the 17q21.31 region and some genes (LRRC37A4P, LINC02210, and DND1P1) exhibit considerable variation in the cerebellum across the lifespan.

CONCLUSIONS

Our findings support a shared genetic basis for SCZ and ASD. A common genetic variant, rs2696609, located in the Chr17q21.31 locus, may exert differential risk regulation on SCZ and ASD by altering brain structure. Future studies should focus on the role of pseudogenes, lncRNAs, and cerebellum in synaptic pruning and neurodevelopmental disorders.

Assessing Trial-by-Trial Electrophysiological and Behavioral Markers of Attentional Control and Sensory Precision in Psychotic and Mood Disorders

BACKGROUND AND HYPOTHESIS

The current study investigated the extent to which changes in attentional control contribute to performance on a visual perceptual discrimination task, on a trial-by-trial basis in a transdiagnostic clinical sample.

STUDY DESIGN

Participants with schizophrenia (SZ; N = 58), bipolar disorder (N = 42), major depression disorder (N = 51), and psychiatrically healthy controls (N = 92) completed a visual perception task in which stimuli appeared briefly. The design allowed us to estimate the lapse rate and the precision of perceptual representations of the stimuli. Electroencephalograms (EEG) were recorded to examine pre-stimulus activity in the alpha band (8-13 Hz), overall and in relation to behavior performance on the task.

STUDY RESULTS

We found that the attention lapse rate was elevated in the SZ group compared with all other groups. We also observed group differences in pre-stimulus alpha activity, with control participants showing the highest levels of pre-stimulus alpha when averaging across trials. However, trial-by-trial analyses showed within-participant fluctuations in pre-stimulus alpha activity significantly predicted the likelihood of making an error, in all groups. Interestingly, our analysis demonstrated that aperiodic contributions to the EEG signal (which affect power estimates across frequency bands) serve as a significant predictor of behavior as well.

CONCLUSIONS

These results confirm the elevated attention lapse rate that has been observed in SZ, validate pre-stimulus EEG markers of attentional control and their use as a predictor of behavior on a trial-by-trial basis, and suggest that aperiodic contributions to the EEG signal are an important target for further research in this area, in addition to alpha-band activity.

Racial disparities with PRN medication usage in inpatient psychiatric treatment

Racial disparities in psychiatric diagnoses and treatment have significant public health implications, contributing to inequities in healthcare outcomes. We specifically examined racial disparities regarding pro re nata (PRN), or as needed, medications. Data from 14,616 encounters across 2019-2020 within Community Health Network's inpatient psychiatric setting in Indianapolis, Indiana were included in this study. Due to the demographic sample size, analyses were narrowed to Black and White patients. Primary outcomes included comparisons across race for all PRN administrations and PRN administrations of antipsychotics vs. non-antipsychotics. Logistic regression was used to examine associations between race and PRN administrations by medication category, including all antipsychotics vs. non-antipsychotics overall, hydroxyzine, and lorazepam, independently. Significant differences in the percentage of administrations between Black and White patients were observed. Black patients received more PRN medications overall (71.0%) compared to White patients (67.7%) (p < 0.01). Further, while 17.7% of Black patients were administered PRN antipsychotics, this was true for only 8.2% of White patients (p < 0.001). When comparing antipsychotic PRNs with non-antipsychotic, hydroxyzine, and lorazepam PRNs, independently, Black patients were 58% (OR 1.58, p < 0.001), 109% (OR 2.09, p < 0.001), and 32% (OR 1.32, p < 0.001), more likely to receive antipsychotic PRNs, respectively, than White patients, controlling for sex, age, length of stay, and psychotic disorder diagnosis. Our study identifies yet another area of medical care with significant racial disparities. In this analysis of PRN medications during psychiatric admission, we identified significant differences in medication utilization by race. This information provides a basis for further investigation of disparities in patient-centered data.

Simultaneous EEG-fMRI Investigation of Rhythm-Dependent Thalamo-Cortical Circuits Alteration in Schizophrenia

Schizophrenia is accompanied by aberrant interactions of intrinsic brain networks. However, the modulatory effect of electroencephalography (EEG) rhythms on the functional connectivity (FC) in schizophrenia remains unclear. This study aims to provide new insight into network communication in schizophrenia by integrating FC and EEG rhythm information. After collecting simultaneous resting-state EEG-functional magnetic resonance imaging data, the effect of rhythm modulations on FC was explored using what we term "dynamic rhythm information." We also investigated the synergistic relationships among three networks under rhythm modulation conditions, where this relationship presents the coupling between two brain networks with other networks as the center by the rhythm modulation. This study found FC between the thalamus and cortical network regions was rhythm-specific. Further, the effects of the thalamus on the default mode network (DMN) and salience network (SN) were less similar under alpha rhythm modulation in schizophrenia patients than in controls ([Formula: see text]). However, the similarity between the effects of the central executive network (CEN) on the DMN and SN under gamma modulation was greater ([Formula: see text]), and the degree of coupling was negatively correlated with the duration of disease ([Formula: see text], [Formula: see text]). Moreover, schizophrenia patients exhibited less coupling with the thalamus as the center and greater coupling with the CEN as the center. These results indicate that modulations in dynamic rhythms might contribute to the disordered functional interactions seen in schizophrenia.

National Cohort Data Suggests an Association Between Serious Mental Illness and Audiometric Hearing Loss

OBJECTIVE

To explore whether there is an association between serious mental illness (SMI) and hearing loss (HL) among US Hispanic adults.

STUDY DESIGN AND SETTING

Cross-sectional epidemiological study (Hispanic Community Health Study), including multicentered US volunteers.

METHODS

Multivariable linear regressions were conducted to study the association between SMI and HL. Adjustments were made for potential confounders including age, sex, education, vascular disease (hypertension or diabetes mellitus), and cognition. SMI was defined by (1) antipsychotic medication classification and (2) the use of at least 1 antipsychotic medication specifically used to treat SMI in clinical psychiatric practice. HL was measured by pure tone audiometry.

RESULTS

A total of 7581 subjects had complete data. The mean age was 55.2 years (SD = 7.5 years) and the mean pure tone average in the better ear was 16.8 dB (SD = 10.7 dB). A total of 194 (2.6%) subjects were taking a HCHS-defined antipsychotic and 98 (1.3%) were taking at least 1 antipsychotic specifically used to treat SMI. On multivariable regression, use of HCHS's classified antipsychotics was associated with 3.75 dB worse hearing (95% confidence interval [CI] = 2.36-5.13, P < .001) and use of antipsychotics specific for SMI was associated with 4.49 dB worse hearing (95% CI = 2.56-6.43, P < .001) compared to those not using antipsychotics.

CONCLUSION

SMI, as defined by either the use of HCHS-defined antipsychotics or the use of antipsychotic medication specific for SMI, is associated with worse hearing, controlling for potential confounders. Whether SMI contributes to HL, antipsychotic medication (through ototoxicity) contributes to HL, or whether HL contributes to SMI is unknown and warrants further investigation.

The relationship between childhood trauma, psychotic symptoms, and cognitive schemas in patients with schizophrenia, their siblings, and healthy controls: results from the EU-GEI study

BACKGROUND

The relationship between childhood trauma (CT) and psychotic symptoms in patients with schizophrenia (SCZ), and subthreshold psychotic experiences in non-clinical populations is well-established. However, little is known about the relationship between subtypes of trauma and specific symptoms in patients, their siblings, and controls. It is also not clear which variables mediate the relationship between trauma and psychotic symptoms.

METHODS

Seven hundred and forty-two patients with SCZ, 718 of their unaffected siblings and 1039 controls from three EU-GEI sites were assessed for CT, symptom severity, and cognitive schemas about self/others. CT was assessed with the Childhood Trauma Questionnaire, and cognitive schemas were assessed by The Brief Core Schema Scale.

RESULTS

Patients with psychosis were affected by CT more than their siblings and controls in all domains. Childhood emotional abuse and neglect were more common in siblings than controls. CT was related to negative cognitive schemas toward self/others in patients, siblings, and controls. We found that negative schemas about self-mediated the relationship between emotional abuse and thought withdrawal and thought broadcasting. Approximately 33.9% of the variance in these symptoms was explained by the mediator. It also mediated the relationship between sexual abuse and persecutory delusions in SCZ.

CONCLUSIONS

Our findings suggest that childhood abuse and neglect are more common in patients with schizophrenia than their siblings and healthy controls, and have different impacts on clinical domains which we searched. The relationship between CT and positive symptoms seems to be mediated by negative cognitive schemas about self in schizophrenia.

Adaptive coding of reward in schizophrenia, its change over time and relation to apathy

Adaptive coding of reward is the process by which neurons adapt their response to the context of available compensations. Higher rewards lead to a stronger brain response, but the increase of the response depends on the range of available rewards. A steeper increase is observed in a narrow range, and a more gradual slope in a wider range. In schizophrenia, adaptive coding appears affected in different domains, and in the reward domain in particular. Here we tested adaptive coding of reward in a large group of patients with schizophrenia (N = 86) and controls (N = 66). We assessed 1) the association between adaptive coding deficits and symptoms; 2) the longitudinal stability of deficits (the same task was performed three months apart); 3) the stability of results between two experimental sites. We used fMRI and the Monetary Incentive Delay task to assess participant' adaptation to two different reward ranges: a narrow and a wide range. We used a region of interest analysis, evaluating adaptation within striatal and visual regions. Patients and controls underwent a full demographic and clinical assessment. We found reduced adaptive coding in patients, due to a decreased slope in the narrow reward range, with respect to that of control participants in striatal but not visual regions. This pattern was observed at both research sites. Upon re-test, patients increased their narrow range slopes, showing improved adaptive coding, whereas controls slightly reduced them. At re-test, patients with overly steep slopes in the narrow range also showed higher levels of negative symptoms. Our data confirm deficits in reward adaptation in schizophrenia and reveal a practice effect in patients, leading to improvement, with steeper slopes upon retest. However, in some patients, an overly steep slope may result in poor discriminability of larger rewards, due to early saturation of the brain response. Together, the loss of precision of reward representation in new (first exposure, underadaptation) and more familiar (re-test, overadaptation) situations may contribute to the multiple motivational symptoms in schizophrenia.

Craniofacial anomalies in schizophrenia-relevant GFAP.HMOX10-12m mice

Subtle craniofacial dysmorphology has been reported in schizophrenia patients. This dysmorphology includes midline facial elongation, frontonasal anomalies and a sexually dimorphic deviation from normal directional asymmetry of the face, with male patients showing reduced and female patients showing enhanced facial asymmetry relative to healthy control subjects. GFAP.HMOX10-12m transgenic mice (Mus musculus) that overexpress heme oxygenase-1 in astrocytes recapitulate many schizophrenia-relevant neurochemical, neuropathological and behavioral features. As morphogenesis of the brain, skull and face are highly interrelated, we hypothesized that GFAP.HMOX10-12m mice may exhibit craniofacial anomalies similar to those reported in persons with schizophrenia. We examined craniofacial anatomy in male GFAP.HMOX10-12m mice and wild-type control mice at the early adulthood age of 6-8 months. We used computer vision techniques for the extraction and analysis of mouse head shape parameters from systematically acquired 2D digital images, and confirmed our results with landmark-based geometric morphometrics. We performed skull bone morphometry using digital calipers to take linear distance measurements between known landmarks. Relative to controls, adult male GFAP.HMOX10-12m mice manifested craniofacial dysmorphology including elongation of the nasal bones, alteration of head shape anisotropy and reduction of directional asymmetry in facial shape features. These findings demonstrate that GFAP.HMOX10-12m mice exhibit craniofacial anomalies resembling those described in schizophrenia patients, implicating heme oxygenase-1 in their development. As a preclinical mouse model, GFAP.HMOX10-12m mice provide a novel opportunity for the study of the etiopathogenesis of craniofacial and other anomalies in schizophrenia and related disorders.

Decreased oral function in Japanese inpatients with schizophrenia

AIM

Oral function in patients with schizophrenia has not been well-characterized. To address this, we performed a cross-sectional study of oral function in Japanese inpatients with schizophrenia.

METHODS

We measured oral function, including occlusal force, tongue-lip motor function, tongue pressure, and masticatory function in 130 Japanese inpatients with schizophrenia. We then compared the frequency of clinical signs of oral hypofunction among 63 non-elderly and 67 elderly inpatients with schizophrenia, as well as data from 98 elderly control participants from a previous Japanese study.

RESULTS

The frequency of reduced occlusal force was significantly higher in the elderly inpatients (76.2%) than in the non-elderly inpatients (43.9%) and elderly controls (43.9%). The frequency of decreased tongue-lip motor function in non-elderly inpatients (96.8%) and elderly inpatients (97.0%) was significantly higher than that in elderly controls (56.1%). The frequency of decreased tongue pressure in non-elderly inpatients (66.1%) and elderly inpatients (80.7%) was significantly higher than that in elderly controls (43.9%). Finally, the frequency of decreased masticatory function was highest in elderly inpatients (76.5%), followed by non-elderly inpatients (54.8%) and elderly controls (15.3%).

CONCLUSION

Oral function was decreased in both non-elderly and elderly Japanese inpatients with schizophrenia compared with elderly controls.

Variations to plasma H2O2 levels and TAC in chronical medicated and treatment-resistant male schizophrenia patients: Correlations with psychopathology

Accumulating evidence suggests that imbalanced oxidative stress (OS) may contribute to the mechanism of schizophrenia. The aim of the present study was to evaluate the associations of OS parameters with psychopathological symptoms in male chronically medicated schizophrenia (CMS) and treatment-resistant schizophrenia (TRS) patients. Levels of hydrogen peroxide (H2O2), hydroxyl radical (·OH), peroxidase (POD), α-tocopherol (α-toc), total antioxidant capacity (TAC), matrix metalloproteinase-9 (MMP-9), and tissue inhibitor of metalloproteinases-1 (TIMP-1) were assayed in males with CMS and TRS, and matched healthy controls. Schizophrenia symptoms were assessed using the Positive and Negative Syndrome Scale (PANSS). The results demonstrated significant differences in the variables H2O2 (F = 5.068, p = 0.008), ·OH (F = 31.856, p < 0.001), POD (F = 14.043, p < 0.001), α-toc (F = 3.711, p = 0.027), TAC (F = 24.098, p < 0.001), and MMP-9 (F = 3.219, p = 0.043) between TRS and CMS patients and healthy controls. For TRS patients, H2O2 levels were correlated to the PANSS positive subscale (r = 0.386, p = 0.032) and smoking (r = -0,412, p = 0.021), while TAC was significantly negatively correlated to the PANSS total score (r = -0.578, p = 0.001) and POD and TAC levels were positively correlated to body mass index (r = 0.412 and 0.357, p = 0.021 and 0.049, respectively). For patients with CMS, ·OH levels and TAC were positively correlated to the PANSS general subscale (r = 0.308, p = 0.031) and negatively correlated to the PANSS total score (r = -0.543, p < 0.001). Furthermore, H2O2, α-toc, and ·OH may be protective factors against TRS, and POD was a risk factor. Patients with CMS and TRS exhibit an imbalance in OS, thus warranting future investigations.

Co-administration of probiotic and vitamin D significantly improves cognitive function in schizophrenic patients: A double-blinded randomized controlled trial

AIM

Manipulation of the intestinal microbiome and supplying vitamin D can attenuate psychiatric symptoms in schizophrenic patients. The current study tried to evaluate the effects of probiotic/vitamin D supplementation on the cognitive function and disease severity of schizophrenic patients.

METHODS

In the present study, 70 patients (aged 18-65) with schizophrenia were recruited. Participants were randomly allocated to the placebo (n = 35) and intervention (probiotic supplements+400 IU vitamin D, n = 35) groups. Severity of disease and cognitive function (primary outcomes) were evaluated by Positive and Negative Syndrome Scale (PANSS) and Montreal Cognitive Assessment (MoCA) tests, respectively. Moreover, lipid profile, body mass index (BMI), gastrointestinal (GI) problems, serum C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) were evaluated as secondary outcomes.

RESULTS

A total of 69 patients completed the study. The MoCA score was increased by 1.96 units in the probiotic-containing supplement group compared to the placebo (p = 0.004). Also, the percentage of subjects with MoCA score ≥ 26 rose significantly in the intervention group (p = 0.031). Moreover, TC (p = 0.011), FBS (p = 0.009), and CRP (p < 0.001) significantly decreased in the supplement group compared to the placebo. Although the probiotic supplement reduced PANSS score by 2.82 units, the difference between the study groups was not statistically significant (p = 0.247).

CONCLUSION

Co-administration of probiotics and vitamin D has beneficial effects on the improvement of cognitive function in schizophrenic patients.

Exploring clozapine pharmacokinetics in Tunisian schizophrenic patients: A population-based modelling approach investigating the impact of genetic and non-genetic variables

Clozapine is characterized by a large within- and between-patient variability in its pharmacokinetics, attributed to non-genetic and genetic factors. A cross-sectional analysis of clozapine trough concentration (Clz C0) issued from Tunisian schizophrenic patients was collected and analysed using a nonparametric modelling approach. We assessed the impact of demographic covariates (age, weight and sex), patient's habits (smoking status, alcohol and caffeine intake) and the genetic factors (CYP1A2*1C, CYP1A2*1F and CYP2C19*2 polymorphisms) on each pharmacokinetic parameter. An external validation of this pharmacokinetic model using an independent data set was performed. Fit goodness between observed- and individual-predicted data was evaluated using the mean prediction error (% MPE), the mean absolute prediction error (% MAPE) as a measure of bias, and the root mean squared error (% RMSE) as a measure of precision. Sixty-three CLz C0 values issued from 51 schizophrenic patients were assessed in this study and divided into building and validation groups. CYP1A2*1F polymorphism and smoking status were the only covariates significantly associated with clozapine clearance. Precision parameters were as follows: 1.02%, 0.95% and 22.4%, respectively, for % MPE, % MAPE and % RMSE. We developed and validated an accurate pharmacokinetic model able to predict Clz C0 in Tunisian schizophrenic patients using the two parameters CYP1A2*1F polymorphism and smoking.

Effort-cost decision-making associated with negative symptoms in schizophrenia and bipolar disorder

Motivational deficits and reduced goal-directed behavior for external rewards have long been considered an important features of negative symptoms in patients with schizophrenia (SCZ). Negative symptoms have also a high prevalence in bipolar disorder (BP). We used a transdiagnostic approach in order to examine association between negative symptoms and effort allocation for monetary rewards. 41 patients with SCZ and 34 patients with BP were enrolled in the study along with 41 healthy controls (HC). Effort-Expenditure for Rewards Task (EEfRT) was used to measure subjects' effort allocation for monetary rewards. Generalized estimating equation models were used to analyze EEfRT choice behavior. Negative symptoms were assessed using the Brief Negative Symptom Scale (BNSS). SCZ and BP groups expended lower effort to obtain a monetary rewards compared to HC. Severity of negative symptoms was negatively correlated with EEfRT performance in both diagnostic groups. Each diagnostic group showed lower effort allocation for monetary rewards compared to HC suggesting reduced motivation for monetary rewards. In addition, our results suggest that abnormal effort-based decision-making might be a transdiagnostic factor underlying negative symptoms.

Higher-order functional brain networks and anterior cingulate glutamate + glutamine (Glx) in antipsychotic-naïve first episode psychosis patients

Human connectome studies have provided abundant data consistent with the hypothesis that functional dysconnectivity is predominant in psychosis spectrum disorders. Converging lines of evidence also suggest an interaction between dorsal anterior cingulate cortex (dACC) cortical glutamate with higher-order functional brain networks (FC) such as the default mode (DMN), dorsal attention (DAN), and executive control networks (ECN) in healthy controls (HC) and this mechanism may be impaired in psychosis. Data from 70 antipsychotic-medication naïve first-episode psychosis (FEP) and 52 HC were analyzed. 3T Proton magnetic resonance spectroscopy (1H-MRS) data were acquired from a voxel in the dACC and assessed correlations (positive FC) and anticorrelations (negative FC) of the DMN, DAN, and ECN. We then performed regressions to assess associations between glutamate + glutamine (Glx) with positive and negative FC of these same networks and compared them between groups. We found alterations in positive and negative FC in all networks (HC > FEP). A relationship between dACC Glx and positive and negative FC was found in both groups, but when comparing these relationships between groups, we found contrasting associations between these variables in FEP patients compared to HC. We demonstrated that both positive and negative FC in three higher-order resting state networks are already altered in antipsychotic-naïve FEP, underscoring the importance of also considering anticorrelations for optimal characterization of large-scale functional brain networks as these represent biological processes as well. Our data also adds to the growing body of evidence supporting the role of dACC cortical Glx as a mechanism underlying alterations in functional brain network connectivity. Overall, the implications for these findings are imperative as this particular mechanism may differ in untreated or chronic psychotic patients; therefore, understanding this mechanism prior to treatment could better inform clinicians.Clinical trial registration: Trajectories of Treatment Response as Window into the Heterogeneity of Psychosis: A Longitudinal Multimodal Imaging Study, NCT03442101 . Glutamate, Brain Connectivity and Duration of Untreated Psychosis (DUP), NCT02034253 .

New role of platelets in schizophrenia: predicting drug response

Background

Elevated platelet count (PLTc) is associated with first-episode schizophrenia and adverse outcomes in individuals with precursory psychosis. However, the impact of antipsychotic medications on PLTc and its association with symptom improvement remain unclear.

Aims

We aimed to investigate changes in PLTc levels following antipsychotic treatment and assess whether PLTc can predict antipsychotic responses and metabolic changes after accounting for other related variables.

Methods

A total of 2985 patients with schizophrenia were randomised into seven groups. Each group received one of seven antipsychotic treatments and was assessed at 2, 4 and 6 weeks. Clinical symptoms were evaluated using the positive and negative syndrome scale (PANSS). Additionally, we measured blood cell counts and metabolic parameters, such as blood lipids. Repeated measures analysis of variance was used to examine the effect of antipsychotics on PLTc changes, while structural equation modelling was used to assess the predictive value of PLTc on PANSS changes.

Results

PLTc significantly increased in patients treated with aripiprazole (F=6.00, p=0.003), ziprasidone (F=7.10, p<0.001) and haloperidol (F=3.59, p=0.029). It exhibited a positive association with white blood cell count and metabolic indicators. Higher baseline PLTc was observed in non-responders, particularly in those defined by the PANSS-negative subscale. In the structural equation model, PLTc, white blood cell count and a latent metabolic variable predicted the rate of change in the PANSS-negative subscale scores. Moreover, higher baseline PLTc was observed in individuals with less metabolic change, although this association was no longer significant after accounting for baseline metabolic values.

Conclusions

Platelet parameters, specifically PLTc, are influenced by antipsychotic treatment and could potentially elevate the risk of venous thromboembolism in patients with schizophrenia. Elevated PLTc levels and associated factors may impede symptom improvement by promoting inflammation. Given PLTc's easy measurement and clinical relevance, it warrants increased attention from psychiatrists.

Trial registration number

ChiCTR-TRC-10000934.

Transplantation of gut microbiota derived from patients with schizophrenia induces schizophrenia-like behaviors and dysregulated brain transcript response in mice

Schizophrenia (SCZ), as a neurodevelopmental disorder and devastating disease, affects approximately 1% of the world population. Although numerous studies have attempted to elucidate the causes of SCZ occurrence, it is not clearly understood. Recently, the emerging roles of the gut microbiota in a range of brain disorders, including SCZ, have attracted much attention. While the molecular mechanism of gut microbiota in regulating the pathogenesis of SCZ is still lacking. Here, we first confirmed the difference of gut microbiome between SCZ patients and healthy controls, and then, we performed fecal microbiota transplantation (FMT) to clarify the roles of SCZ patients-derived microbiota in a specific pathogen free (SPF) mice model. 16 S rDNA sequencing confirmed that a significant difference of gut microbiome was present between two groups of FMT mice, which has a similar trend with the above human gut microbiome. Furthermore, we found that transplantation of fecal microbiota from SCZ patients into SPF mice was sufficient to induce schizophrenia-like (SCZ-like) symptoms, such as deficits in sociability and hyperactivity. Furthermore, the brains of mice colonized with SCZ microbiota displayed dysregulated transcript response and alternative splicing of SCZ-relevant genes. Moreover, 10 key genes were identified to be correlated with SCZ by an integrative transcriptome data analysis. Finally, 4 key genes were identified to be correlated with the 12 differential genera between two groups of FMT mice. Our results thus demonstrated that the gut microbiome might modify the transcriptomic profile in the brain, thereby modulating social behavior, and our present study can help better understand the link between gut microbiota and SCZ pathogenesis through the gut-brain axis.

Early auditory processing abnormalities alter individual learning trajectories and sensitivity to computerized cognitive training in schizophrenia

BACKGROUND

Auditory system plasticity is a promising target for neuromodulation, cognitive rehabilitation and therapeutic development in schizophrenia (SZ). Auditory-based targeted cognitive training (TCT) is a 'bottom up' intervention designed to enhance the speed and accuracy of auditory information processing, which has been shown to improve neurocognition in certain SZ patients. However, the dynamics of TCT learning as a function of training exercises and their impact on neurocognitive functioning and therapeutic outcomes are unknown.

METHODS

Forty subjects (SZ, n = 21; healthy subjects (HS), n = 19) underwent comprehensive clinical, cognitive, and auditory assessments, including measurements of auditory processing speed (APS) at baseline and after 1-h of TCT. SZ patients additionally completed 30-hours of TCT and repeated assessments ~10-12 weeks later.

RESULTS

SZ patients were deficient in APS at baseline (d = 0.96, p < 0.005) relative to HS. After 1-h of TCT, analyses revealed significant main effects of diagnosis (d = 1.75, p = 0.002) and time (d = 1.04, p < 0.001), and a diagnosis × time interaction (d = 0.85, p = 0.02) on APS. APS learning effects were robust after 1-h in SZ patients (d = 1.47, p < 0.001) and persisted throughout the 30-h of training. Baseline APS was associated with verbal learning gains after 30-h of TCT (r = 0.51, p = 0.02) in SZ.

CONCLUSIONS

TCT learning metrics may have prognostic utility and aid in the prospective identification of individuals likely to benefit from TCT. Future experimental medicine studies may advance predictive algorithms that enhance TCT-related clinical, cognitive and functional outcomes.

Adverse Events Reporting in Digital Interventions Evaluations for Psychosis: A Systematic Literature Search and Individual Level Content Analysis of Adverse Event Reports

BACKGROUND

Digital health interventions (DHIs) have significant potential to upscale treatment access to people experiencing psychosis but raise questions around patient safety. Adverse event (AE) monitoring is used to identify, record, and manage safety issues in clinical trials, but little is known about the specific content and context contained within extant AE reports. This study aimed to assess current AE reporting in DHIs.

STUDY DESIGN

A systematic literature search was conducted by the iCharts network (representing academic, clinical, and experts by experience) to identify trials of DHIs in psychosis. Authors were invited to share AE reports recorded in their trials. A content analysis was conducted on the shared reports.

STUDY RESULTS

We identified 593 AE reports from 18 DHI evaluations, yielding 19 codes. Only 29 AEs (4.9% of total) were preidentified by those who shared AEs as being related to the intervention or trial procedures. While overall results support the safety of DHIs, DHIs were linked to mood problems and psychosis exacerbation in a few cases. Additionally, 27% of studies did not report information on relatedness for all or at least some AEs; 9.6% of AE reports were coded as unclear because it could not be determined what had happened to participants.

CONCLUSIONS

The results support the safety of DHIs, but AEs must be routinely monitored and evaluated according to best practice. Individual-level analyses of AEs have merit to understand safety in this emerging field. Recommendations for best practice reporting in future studies are provided.

Glymphatic System Dysfunction Underlying Schizophrenia Is Associated With Cognitive Impairment

BACKGROUND AND HYPOTHESIS

Despite the well-documented structural and functional brain changes in schizophrenia, the potential role of glymphatic dysfunction remains largely unexplored. This study investigates the glymphatic system's function in schizophrenia, utilizing diffusion tensor imaging (DTI) to analyze water diffusion along the perivascular space (ALPS), and examines its correlation with clinical symptoms.

STUDY DESIGN

A cohort consisting of 43 people with schizophrenia and 108 healthy controls was examined. We quantified water diffusion metrics along the x-, y-, and z-axis in both projection and association fibers to derive the DTI-ALPS index, a proxy for glymphatic activity. The differences in the ALPS index between groups were analyzed using a 2-way ANCOVA controlling for age and sex, while partial correlations assessed the association between the ALPS index and clinical variables.

STUDY RESULTS

People with schizophrenia showed a significantly reduced DTI-ALPS index across the whole brain and within both hemispheres (F = 9.001, P = .011; F = 10.024, P = .011; F = 5.927, P = .044; false discovery rate corrected), indicating potential glymphatic dysfunction in schizophrenia. The group by cognitive performance interaction effects on the ALPS index were not observed. Moreover, a lower ALPS index was associated with poorer cognitive performance on specific neuropsychological tests in people with schizophrenia.

CONCLUSION

Our study highlights a lower ALPS index in schizophrenia, correlated with more pronounced cognitive impairments. This suggests that glymphatic dysfunction may contribute to the pathophysiology of schizophrenia, offering new insights into its underlying mechanisms.

Evaluation of quality of life in patients with schizophrenia: An inpatient social welfare institution-based cross-sectional study

Schizophrenia is a chronic mental illness with a poor quality of life (QoL). The main aim of this study was to measure the QoL and factors that affect the QoL of patients with schizophrenia placed in a social welfare institution. This cross-sectional study included 287 patients with schizophrenia who were treated in a long-stay social care institution in which QoL was assessed using five different instruments: the World Health Organization Quality of Life scale, the EuroQoL Five-Dimension-Five-Level scale (including the visual analog scale), the Quality of Life Enjoyment and Satisfaction Questionnaire - Short Form, and the Brief Psychiatric Rating Scale. To determine the impact of patients' characteristics on score values, multiple linear regression using backward elimination was employed. Due to non-normality in the distribution of the dependent variables, a Box-Cox power transformation was applied to each dependent variable prior to conducting multiple linear regression analysis. Results revealed that patients with schizophrenia have lower QoL. Our study revealed that age, level of education, type of accommodation, type of pavilion, age of onset of the disease, number of prescribed antipsychotics, number of psychiatric comorbidities, duration of therapy, and the number of daily doses of antipsychotics are dominant contributors to the QoL in patients with schizophrenia who were treated in social welfare institution.

The Ethiopian Cognitive Assessment battery in Schizophrenia (ECAS): a validation study

Cognitive impairment is common in people with schizophrenia (PWS). To detect the presence and its consequences, cognitive measures with sound psychometric properties are needed. However, these are lacking especially in low-income countries. Hence, we developed the Ethiopian Cognitive Assessment battery in Schizophrenia (ECAS). In this study, we evaluated the psychometric properties of the ECAS in a cross-sectional study involving 350 PWS. Confirmatory factor analysis demonstrated a one-factor solution. ECAS score correlated significantly but weakly with a disability measure (r = -0.13, p = 0.02) and symptom dimensions of PANSS (r between -0.12 and -0.29, p < 0.05), except for positive symptoms (r = -0.10, p > 0.05). Years of education (β = 0.12, 95% CI (0.09, 0.14), p < 0.001), male sex (β = 0.22, 95% CI (0.05, 0.39)), age β = -0.02, 95% CI (-0.03, -0.01), and medication side effects (β = -0.03, 95% CI (-0.06, -0.01), p = 0.021) were significantly associated with the composite score of ECAS. The Item Response Theory analysis showed that the tool best functions among participants with moderate cognitive impairment (difficulty coefficient between -1.12 and 0.27). The Differential Item Functioning analyses showed that education had a positive contribution on Digit Symbol Substitution Test (MH OR = 2.64, 95% CI (1.34, 5.20)). The results showed that ECAS is valid in assessing cognition in PWS in low-resource settings.

Further clarification of cognitive processes of prospective memory in schizophrenia by comparing eye-tracking and ecologically-valid measurements

The aim of this study is to compare ecologically-valid measure (the Cambridge Prospective Memory Test, CAMPROMPT) and laboratory measure (eye-tracking paradigm) in assessing prospective memory (PM) in individuals with schizophrenia spectrum disorders (SSDs). In addition, eye-tracking indices are used to examine the relationship between PM and other cognitive domains in SSDs patients. Initially, the study sample was formed by 32 SSDs patients and 32 healthy control subjects (HCs) who were matched in sociodemographic profile and the performance on CAMPROMPT. An eye-tracking paradigm was employed to examine the differences in PM accuracy and key cognitive processes (e.g., cue monitoring) between the two groups. Additional 31 patients were then recruited to investigate the relationship between PM cue monitoring, other cognitive functions, and the severity of clinical symptoms within the SSDs group. The monitoring of PM cue was reflected in total fixation time and total fixation counts for distractor words. Cognitive functions were assessed using the Chinese version of the MATRICS Consensus Cognitive Battery (MCCB). The Positive and Negative Syndrome Scale (PANSS) was applied to assess psychopathology. SSDs patients exhibited fewer total fixation counts for distractor words and lower PM accuracy compared to HCs, even though they were priori matched on CAMPROMPT. Correlation analysis within the SSDs group (63 cases) indicated a negative correlation between PM accuracy and PANSS total score, and a positive correlation with working memory and attention/vigilance. Regression analysis within the SSDs group revealed that higher visual learning and lower PANSS total scores independently predicted more total fixation counts on distractor words. Impairment in cue monitoring is a critical factor in the PM deficits in SSDs. The eye-tracking laboratory paradigm has advantages over the ecologically-valid measurement in identifying the failure of cue detection, making it a more sensitive tool for PM deficits in patients with SSDs.

Distinct Volume Alterations of Thalamic Nuclei Across the Schizophrenia Spectrum

BACKGROUND AND HYPOTHESIS

Abnormal thalamic nuclei volumes and their link to cognitive impairments have been observed in schizophrenia. However, whether and how this finding extends to the schizophrenia spectrum is unknown. We hypothesized a distinct pattern of aberrant thalamic nuclei volume across the spectrum and examined its potential associations with cognitive symptoms.

STUDY DESIGN

We performed a FreeSurfer-based volumetry of T1-weighted brain MRIs from 137 healthy controls, 66 at-risk mental state (ARMS) subjects, 89 first-episode psychosis (FEP) individuals, and 126 patients with schizophrenia to estimate thalamic nuclei volumes of six nuclei groups (anterior, lateral, ventral, intralaminar, medial, and pulvinar). We used linear regression models, controlling for sex, age, and estimated total intracranial volume, both to compare thalamic nuclei volumes across groups and to investigate their associations with positive, negative, and cognitive symptoms.

STUDY RESULTS

We observed significant volume alterations in medial and lateral thalamic nuclei. Medial nuclei displayed consistently reduced volumes across the spectrum compared to controls, while lower lateral nuclei volumes were only observed in schizophrenia. Whereas positive and negative symptoms were not associated with reduced nuclei volumes across all groups, higher cognitive scores were linked to lower volumes of medial nuclei in ARMS. In FEP, cognition was not linked to nuclei volumes. In schizophrenia, lower cognitive performance was associated with lower medial volumes.

CONCLUSIONS

Results demonstrate distinct thalamic nuclei volume reductions across the schizophrenia spectrum, with lower medial nuclei volumes linked to cognitive deficits in ARMS and schizophrenia. Data suggest a distinctive trajectory of thalamic nuclei abnormalities along the course of schizophrenia.

Correlation Between Cortical Thickness Abnormalities of the Olfactory Sulcus and Olfactory Identification Disorder and Persistent Auditory Verbal Hallucinations in Chinese Patients With Chronic Schizophrenia

BACKGROUND AND HYPOTHESIS

Persistent auditory verbal hallucinations (pAVHs) and olfactory identification impairment are common in schizophrenia (SCZ), but the neuroimaging mechanisms underlying both pAVHs and olfactory identification impairment are unclear. This study aimed to investigate whether pAVHs and olfactory identification impairment in SCZ patients are associated with changes in cortical thickness.

STUDY DESIGN

In this study, cortical thickness was investigated in 78 SCZ patients with pAVHs (pAVH group), 58 SCZ patients without AVHs (non-AVH group), and 83 healthy controls (HC group) using 3T magnetic resonance imaging. The severity of pAVHs was assessed by the Auditory Hallucination Rating Scale. Olfactory identification deficits were assessed using the Odor Stick Identification Test for Japanese (OSIT-J). In addition, the relationship between the severity of pAVHs and olfactory identification disorder and cortical thickness abnormalities was determined.

STUDY RESULTS

Significant reductions in cortical thickness were observed in the right medial orbital sulcus (olfactory sulcus) and right orbital sulcus (H-shaped sulcus) in the pAVH group compared to both the non-AVH and HC groups (P < .003, Bonferroni correction). Furthermore, the severity of pAVHs was found to be negatively correlated with the reduction in cortical thickness in the olfactory sulcus and H-shaped sulcus. Additionally, a decrease in cortical thickness in the olfactory sulcus showed a positive correlation with the OSIT-J scores (P < .05, false discovery rate correction).

CONCLUSIONS

Cortical thickness abnormalities in the olfactory sulcus may be a common neuroimaging mechanism for pAVHs and olfactory identification deficits in SCZ patients.

EEG analysis in patients with schizophrenia based on microstate semantic modeling method

Introduction

Microstate analysis enables the characterization of quasi-stable scalp potential fields on a sub-second timescale, preserving the temporal dynamics of EEG and spatial information of scalp potential distributions. Owing to its capacity to provide comprehensive pathological insights, it has been widely applied in the investigation of schizophrenia (SCZ). Nevertheless, previous research has primarily concentrated on differences in individual microstate temporal characteristics, neglecting potential distinctions in microstate semantic sequences and not fully considering the issue of the universality of microstate templates between SCZ patients and healthy individuals.

Methods

This study introduced a microstate semantic modeling analysis method aimed at schizophrenia recognition. Firstly, microstate templates corresponding to both SCZ patients and healthy individuals were extracted from resting-state EEG data. The introduction of a dual-template strategy makes a difference in the quality of microstate sequences. Quality features of microstate sequences were then extracted from four dimensions: Correlation, Explanation, Residual, and Dispersion. Subsequently, the concept of microstate semantic features was proposed, decomposing the microstate sequence into continuous sub-sequences. Specific semantic sub-sequences were identified by comparing the time parameters of sub-sequences.

Results

The SCZ recognition test was performed on the public dataset for both the quality features and semantic features of microstate sequences, yielding an impressive accuracy of 97.2%. Furthermore, cross-subject experimental validation was conducted, demonstrating that the method proposed in this paper achieves a recognition rate of 96.4% between different subjects.

Discussion

This research offers valuable insights for the clinical diagnosis of schizophrenia. In the future, further studies will seek to augment the sample size to enhance the effectiveness and reliability of this method.

Efficacy of Rivastigmine Augmentation on Positive and Negative Symptoms, General Psychopathology, and Quality of Life in Patients with Chronic Schizophrenia: A Randomized Controlled Trial

The study aimed to assess Rivastigmine augmentation on positive and negative symptoms (PNSs), general psychopathology, and quality of life in patients with chronic Schizophrenia. A double-blind, parallel-design, randomized, placebo-controlled trial of 60 schizophrenia patients was conducted. Intervention group received rivastigmine 3 mg/day + Treatment as Usual (TAU) and the control group: TAU + placebo. Negative and positive symptoms, general psychopathology; and quality of life were measured using Positive and Negative Symptom Scale (PANSS) and Manchester Short Assessment of Quality of Life (MANSA). T-test, ANOVA, and the general univariate linear model tests were used for the analyses. Out of 60 participants, 52 (86.6%) were male. At baseline, no significant relationship was found for demographic and clinical characteristics between intervention and control groups. Between-group analysis indicated that all outcome measures PNSs, general psychopathology symptoms, and QoL score in rivastigmine group was significantly improved (p = 0.001). According to within-group analysis, a significant association was found between Rivastigmine and placebo groups in PNSs (p < 0.05). Rivastigmine augmentation improved PNSs and psychopathology in schizophrenia patients. However, no significant association found for improving the life quality after 8 weeks treatment.

Family psychoeducation in schizophrenia and schizophrenia related disorder, treatment compliance, and suicidal risk reduction: questions about their relationship from a naturalistic observation

Introduction

The Profamille V3.2 multi-family psycho-educational program directed at caregivers of relatives with schizophrenia or schizophrenia related disorder has been shown to decrease the annual prevalence of suicide attempts. It has been reported that psychoeducation of families can sometimes improve compliance with treatment. This study investigates whether the Profamille program improves compliance and thus reduces the risk of suicide among patients.

Method

This is a retrospective study of 179 groups of family caregivers, encompassing 1946 participants enrolled in Module 1 of the Profamille program and followed up one year after completion of the module. Evaluations were conducted using questionnaires filled out by family caregivers at three distinct times: prior to beginning the program, upon its completion, and again one year following its conclusion. The annual prevalence of suicide attempts was measured both before the program began and one year after its conclusion, while compliance to treatment was evaluated at the start and end of the program.

Result

After the Profamille program, the annual prevalence of suicide attempts fell by a factor of 2 (p-value = 0.00002) and patient compliance improved (p-value <0.000001). This reduction in suicide attempts was observed independently of improved compliance. Compliance seems to have an additional effect, but only after participation in the program.

Conclusion

The Profamille program reduces patients' risk of suicide even when patients are not taking the treatment. When family psychoeducation is not proposed in schizophrenia or schizophrenia related disorder, this can represent a loss of chance for patients.

Use of antipsychotic medication, benzodiazepines, and psychiatric hospitalization in cannabis-related versus cannabis-unrelated schizophrenia - a nationwide, register-based cohort study

BACKGROUND

Evidence suggests that cannabis may be a causal factor for development of schizophrenia. We aimed to investigate whether use of antipsychotic medication, benzodiazepines, and psychiatric service use differs among patients with schizophrenia depending on whether psychosis was precipitated by a diagnosis of cannabis use disorder (CUD).

METHODS

We utilized the nationwide Danish registries to identify all individuals with an incident diagnosis of schizophrenia from 1995 to 2016. We also collected information on whether first CUD diagnosis preceded schizophrenia and thus defined a group of potentially cannabis-related schizophrenia. We compared the cannabis-related schizophrenia group both with all non-cannabis-related patients with schizophrenia and with non-cannabis-related patients with schizophrenia that were propensity-score matched to cases using a range of potentially confounding variables.

RESULTS

We included 35 714 people with incident schizophrenia, including 4116 (11.5%) that were cannabis-related. In the unmatched-comparison analyses, there were no clear differences over time in use of antipsychotics and benzodiazepines related to whether the diagnosis of schizophrenia was cannabis-related. After propensity-score matching, use of antipsychotics and benzodiazepines was significantly lower among cannabis-related cases of schizophrenia. In the unmatched comparison, the cannabis-related group had significantly more days admitted than the non-cannabis-related group. This was markedly attenuated after propensity-score matching.

CONCLUSIONS

Our findings indicate the importance of considering cannabis-related cases of schizophrenia as a potentially distinct disorder in terms of prognosis. It is unclear, however, if these differences are due to different biological types of schizophrenia being compared or if they rather indicate behavioral differences such as reduced adherence and treatment-seeking.

A vagal influence on schizophrenia? A nationwide retrospective cohort of vagotomized individuals

Background and Objectives

Emerging preclinical evidence suggests that vagal signals contribute to the development of schizophrenia-related abnormalities in brain and behavior. Whether vagal communication in general, and its impairment in particular, is a risk factor for schizophrenia in humans remains, however, unclear. Vagotomy, the surgical lesion of the vagus nerve, was routinely performed as a treatment for peptic ulcer before modern treatment options were available. Hence, the primary aim of this study was to investigate whether vagotomy modulates the subsequent risk of developing schizophrenia. Moreover, given the existence of diverse vagotomy techniques (i.e., "truncal" or "selective"), our secondary goal was to test whether the extent of denervation modulates the risk of schizophrenia.

Methods

Using a nationwide retrospective matched cohort design, we identified 8,315 vagotomized individuals from the Swedish National Patient Register during the period 1970-2020 and 40,855 non-vagotomized individuals matching for age, sex and type of peptic ulcer. The risk of being diagnosed with schizophrenia and associated psychoses (ICD10 codes F20-29) was analyzed using Cox proportional hazards regression models, including death as competing risk.

Results

When considering all types of vagotomy together, vagotomy was not significantly associated with schizophrenia (HR: 0.91 [0.72; 1.16]). However, truncal vagotomy (which denervates all subdiaphragmatic organs) significantly increased the risk of developing schizophrenia by 69% (HR: 1.69 [1.08; 2.64]), whereas selective vagotomy (which only denervates the stomach) showed no significant association (HR: 0.80 [0.61; 1.04]).

Discussion

Our results provide epidemiological support for the hypothesis that impairments in vagal functions could increase the risk of schizophrenia. Notably, the finding that truncal but not selective vagotomy is associated with an increased risk of schizophrenia raises the possibility that the activity of subdiaphragmatic non-gastric vagal branches may be of particular relevance for the development of schizophrenia.

Assessing regional intracortical myelination in schizophrenia spectrum and bipolar disorders using the optimized T1w/T2w-ratio

BACKGROUND

Dysmyelination could be part of the pathophysiology of schizophrenia spectrum (SCZ) and bipolar disorders (BPD), yet few studies have examined myelination of the cerebral cortex. The ratio of T1- and T2-weighted magnetic resonance images (MRI) correlates with intracortical myelin. We investigated the T1w/T2w-ratio and its age trajectories in patients and healthy controls (CTR) and explored associations with antipsychotic medication use and psychotic symptoms.

METHODS

Patients with SCZ (n = 64; mean age = 30.4 years, s.d. = 9.8), BPD (n = 91; mean age 31.0 years, s.d. = 10.2), and CTR (n = 155; mean age = 31.9 years, s.d. = 9.1) who participated in the TOP study (NORMENT, University of Oslo, Norway) were clinically assessed and scanned using a General Electric 3 T MRI system. T1w/T2w-ratio images were computed using an optimized pipeline with intensity normalization and field inhomogeneity correction. Vertex-wise regression models were used to compare groups and examine group × age interactions. In regions showing significant differences, we explored associations with antipsychotic medication use and psychotic symptoms.

RESULTS

No main effect of diagnosis was found. However, age slopes of the T1w/T2w-ratio differed significantly between SCZ and CTR, predominantly in frontal and temporal lobe regions: Lower T1w/T2w-ratio values with higher age were found in CTR, but not in SCZ. Follow-up analyses revealed a more positive age slope in patients who were using antipsychotics and patients using higher chlorpromazine-equivalent doses.

CONCLUSIONS

While we found no evidence of reduced intracortical myelin in SCZ or BPD relative to CTR, different regional age trajectories in SCZ may suggest a promyelinating effect of antipsychotic medication.

Problem gambling in psychotic disorders: A systematic review and meta-analysis of prevalence

INTRODUCTION

Problem gambling (PBG) is more common in people with mental health disorders, including substance use, bipolar, and personality disorders, than in the general population. Although individuals with psychotic disorders might be expected to be more vulnerable to PBG, fewer studies have focused on this comorbidity. The aim of this review was to estimate the prevalence of PBG in people with psychotic disorders.

METHODS

Medline (Ovid), EMBASE, PsycINFO (Ovid), CINAHL, CENTRAL, Web of science, and ProQuest were searched on November 1, 2023, without language restrictions. Observational and experimental studies including individuals with psychotic disorders and reporting the prevalence of PBG were included. Risk of bias was assessed using the Joanna Briggs Institute critical appraisal for systematic reviews of prevalence data. The pooled prevalence of PBG was calculated using a fixed effects generalized linear mixed model and presented through forest plots.

RESULTS

Of 1271 records screened, 12 studies (n = 3443) were included. The overall prevalence of PBG was 8.7% (95% CI = 7.8%-9.7%, I2 = 69%). A lower prevalence was found in studies with a low risk of bias (5.6%; 95% CI = 4.4%-7.0%) compared with studies with a moderate risk of bias (10.4%; 95% CI = 9.2%-11.7%). Different methods used to assess PBG also contributed to the heterogeneity found.

CONCLUSION

This meta-analysis found substantial heterogeneity, partly due to the risk of bias of the included studies and a lack of uniformity in PBG assessment. Although more research is needed to identify those at increased risk for PBG, its relatively high prevalence warrants routine screening for gambling in clinical practice.

Shared genetic basis and causality between schizophrenia and inflammatory bowel disease: evidence from a comprehensive genetic analysis

BACKGROUND

The comorbidity between schizophrenia (SCZ) and inflammatory bowel disease (IBD) observed in epidemiological studies is partially attributed to genetic overlap, but the magnitude of shared genetic components and the causality relationship between them remains unclear.

METHODS

By leveraging large-scale genome-wide association study (GWAS) summary statistics for SCZ, IBD, ulcerative colitis (UC), and Crohn's disease (CD), we conducted a comprehensive genetic pleiotropic analysis to uncover shared loci, genes, or biological processes between SCZ and each of IBD, UC, and CD, independently. Univariable and multivariable Mendelian randomization (MR) analyses were applied to assess the causality across these two disorders.

RESULTS

SCZ genetically correlated with IBD (rg = 0.14, p = 3.65 × 10−9), UC (rg = 0.15, p = 4.88 × 10−8), and CD (rg = 0.12, p = 2.27 × 10−6), all surpassed the Bonferroni correction. Cross-trait meta-analysis identified 64, 52, and 66 significantly independent loci associated with SCZ and IBD, UC, and CD, respectively. Follow-up gene-based analysis found 11 novel pleiotropic genes (KAT5, RABEP1, ELP5, CSNK1G1, etc) in all joint phenotypes. Co-expression and pathway enrichment analysis illustrated those novel genes were mainly involved in core immune-related signal transduction and cerebral disorder-related pathways. In univariable MR, genetic predisposition to SCZ was associated with an increased risk of IBD (OR 1.11, 95% CI 1.07–1.15, p = 1.85 × 10−6). Multivariable MR indicated a causal effect of genetic liability to SCZ on IBD risk independent of Actinobacteria (OR 1.11, 95% CI 1.06–1.16, p = 1.34 × 10−6) or BMI (OR 1.11, 95% CI 1.04–1.18, p = 1.84 × 10−3).

CONCLUSIONS

We confirmed a shared genetic basis, pleiotropic loci/genes, and causal relationship between SCZ and IBD, providing novel insights into the biological mechanism and therapeutic targets underlying these two disorders.

Food insecurity in adults with severe mental illness: A systematic review with meta-analysis

INTRODUCTION

Food insecurity in adults living with Severe Mental Illness (SMI) is an underresearched area worldwide.

AIM

This systematic review and meta-analysis aimed to identify and collate evidence on food insecurity in adults with SMI, in high- and upper-middle income countries.

METHOD

A comprehensive electronic search was completed up to August 2022. Random effects meta-analysis was undertaken to determine the prevalence and the odds ratio for food insecurity in adults with SMI. Narrative synthesis explored the data further.

RESULTS

Sixteen publications were included (13 in the meta-analysis). The prevalence estimate of food insecurity in adults with SMI was 41% (95% CI: 29% to 53%, I2  = 99.9%, n = 13). Adults with SMI were 3.31 (95% CI: 2.03 to 5.41) times more likely to experience food insecurity than comparators without SMI (z = 6.29, p < .001, I2  = 98.9%, n = 6). Food insecurity appears to be a risk factor for developing SMI.

DISCUSSION

This review suggests adults with SMI living in high- or upper-middle income countries are more likely to experience food insecurity than the general population and that this relationship may be inverse.

IMPLICATIONS FOR PRACTICE

Mental health practitioners should be aware of food insecurity and support individuals with SMI to access sufficient food.

The interaction of RELN-DNMT genes involving in neurotrophin signaling pathway contributes to schizophrenia susceptibility

OBJECTIVE

Schizophrenia belongs to a severe mental illness with complicated clinical presentations, an ill-defined pathogenesis, and no known cause. Many genetic studies imply that polygenic interaction is important in the development of schizophrenia. The main mechanism of the RELN-BDNF-CREB-DNMT signaling pathway in neurodevelopment involves RELN, brain-derived neurotrophic factor (BDNF), transcription factor cyclic adenosine monophosphate response element binding protein (CREB), DNA methyltransferase 1 (DNMT1), as well as DNA methyltransferase 3B (DNMT3B). An early case-control research on 15 polymorphisms in the RELN, CREB, BDNF, DNMT1, and DNMT3B genes was done. A single gene variation has little effect on the pathogenesis of schizophrenia, but the combination of intergenic variation loci has a bigger impact because schizophrenia is a complex polygenic disorder. The objective of the current study sought to explore the impact of genetic interactions between RELN, BDNF, CREB, DNMT1, and DNMT3B on schizophrenia in order to further highlight the genetic factors influencing the risk of schizophrenia.

METHODS

Taking the case-control study design, with the Diagnostic and Statistical Manual of Mental Disorders-Fifth Edition (DSM-5) to be the evaluation norm, 134 individuals suffering from schizophrenia hospitalized in the Third People's Hospital of Zhongshan City within January 2018 to April 2020 (case group) were selected, and 64 healthy individuals (control group) from the same geographical area had been chosen as well. MassArray identified DNMT1 gene single nucleotide polymorphisms (rs2114724 and rs2228611) and DNMT3B gene SNPs (rs2424932, rs1569686, rs6119954, and rs2424908). Using the generalized multifactor dimensionality reduction (GMDR), the RELN-BDNF-CREB-DNMT pathway's gene interactions were examined for their impact on schizophrenia.

RESULTS

GMDR analysis showed that the three-order interaction model RELN (rs2073559, rs2229864)-DNMT3B (rs2424908) was the optimal model (p = 0.001), with the consistency of cross-validation of 10/10 and the test accuracy of 0.8711.

CONCLUSION

The interaction between the RELN (rs2073559, rs2229864)-DNMT3B (rs2424908) may be related to schizophrenia, and large sample sizes should be verified in different population.

Eight-month intensive meditation-based intervention improves refractory hallucinations and delusions and quality of life in male inpatients with schizophrenia: a randomized controlled trial

AIM

This study investigated the impact of an 8-month daily-guided intensive meditation-based intervention (iMI) on persistent hallucinations/delusions and health-related quality of life (QoL) in male inpatients with schizophrenia with treatment-refractory hallucinations and delusions (TRHDs).

METHODS

A randomized controlled trial assigned 64 male inpatients with schizophrenia and TRHD equally to an 8-month iMI plus general rehabilitation program (GRP) or GRP alone. Assessments were conducted at baseline and the third and eighth months using the Positive and Negative Syndrome Scale (PANSS), 36-Item Short Form-36 (SF-36), and Five Facet Mindfulness Questionnaire (FFMQ). Primary outcomes measured PANSS reduction rates for total score, positive symptoms, and hallucinations/delusions items. Secondary outcomes assessed PANSS, SF-36, and FFMQ scores for psychotic symptoms, health-related QoL, and mindfulness skills, respectively.

RESULTS

In the primary outcome, iMI significantly improved the reduction rates of PANSS total score, positive symptoms, and hallucination/delusion items compared with GRP at both the third and eighth months. Treatment response rates (≥25% reduction) for these measures significantly increased in the iMI group at the eighth month. Concerning secondary outcomes, iMI significantly reduced PANSS total score and hallucination/delusion items, while increasing scores in physical activity and mindfulness skills at both the third and eighth months compared with GRP. These effects were more pronounced with an 8-month intervention compared with a 3-month intervention.

CONCLUSIONS

An iMI benefits patients with TRHDs by reducing persistent hallucinations/delusions and enhancing health-related QoL. Longer iMI duration yields superior treatment outcomes.

Brain-based sex differences in schizophrenia: A systematic review of fMRI studies

Schizophrenia is a chronic psychiatric disorder with characteristic symptoms of delusions, hallucinations, lack of motivation, and paucity of thought. Recent evidence suggests that the symptoms of schizophrenia, negative symptoms in particular, vary widely between the sexes and that symptom onset is earlier in males. A better understanding of sex-based differences in functional magnetic resonance imaging (fMRI) studies of schizophrenia may provide a key to understanding sex-based symptom differences. This study aimed to summarize sex-based functional magnetic resonance imaging (fMRI) differences in brain activity of patients with schizophrenia. We searched PubMed and Scopus to find fMRI studies that assessed sex-based differences in the brain activity of patients with schizophrenia. We excluded studies that did not evaluate brain activity using fMRI, did not evaluate sex differences, and were nonhuman or in vitro studies. We found 12 studies that met the inclusion criteria for the current systematic review. Compared to females with schizophrenia, males with schizophrenia showed more blood oxygen level-dependent (BOLD) activation in the cerebellum, the temporal gyrus, and the right precuneus cortex. Male patients also had greater occurrence of low-frequency fluctuations in cerebral blood flow in frontal and parietal lobes and the insular cortex, while female patients had greater occurrence of low-frequency fluctuations in the hippocampus, parahippocampus, and lentiform nucleus. The current study summarizes fMRI studies that evaluated sex-based fMRI brain differences in schizophrenia that may help to shed light on the underlying pathophysiology and further understanding of sex-based differences in the clinical presentation and course of the disorder.