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Duration of untreated psychosis (DUP) is defined as the time from the onset of psychotic symptoms until the first treatment. Studies have shown that longer DUP is associated with poorer response rates to antipsychotic medications and impaired cognition, yet the neurobiologic correlates of DUP are poorly understood. Moreover, it has been hypothesized that untreated psychosis may be neurotoxic. Here, we conducted a comprehensive review of studies that have examined the neurobiology of DUP. Specifically, we included studies that evaluated DUP using a range of neurobiologic and imaging techniques and identified 83 articles that met inclusion and exclusion criteria. Overall, 27 out of the total 83 studies (32.5%) reported a significant neurobiological correlate with DUP. These results provide evidence against the notion of psychosis as structurally or functionally neurotoxic on a global scale and suggest that specific regions of the brain, such as temporal regions, may be more vulnerable to the effects of DUP. It is also possible that current methodologies lack the resolution needed to more accurately examine the effects of DUP on the brain, such as effects on synaptic density. Newer methodologies, such as MR scanners with stronger magnets, PET imaging with newer ligands capable of measuring subcellular structures (e.g., the PET ligand [11C]UCB-J) may be better able to capture these limited neuropathologic processes. Lastly, to ensure robust and replicable results, future studies of DUP should be adequately powered and specifically designed to test for the effects of DUP on localized brain structure and function with careful attention paid to potential confounds and methodological issues.
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Disfunción Cognitiva , Trastornos Psicóticos , Humanos , Encéfalo/patología , Disfunción Cognitiva/patología , Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/patología , Lóbulo Temporal/patologíaRESUMEN
Most research to date has focused on perpetrators of mass murder incidents. Hence, there is little information on victims. We examined 973 mass murders that occurred in the United States between 1900 and 2019 resulting in 5,273 total fatalities and 4,498 nonfatal injuries for a total of 9,771 victims (on average 10 victims per incident). Approximately 64% of victims of mass murder were White individuals, 13% were Black individuals, 6% were Asian individuals, and 14% were Latinx individuals. Given the higher number of nonfatal injuries per non-firearm mass murder event (11.0 vs. 2.8, p < .001), the total number of victims was only 50% higher for mass shootings (5,855 victims) vs. non-firearm mass murder events (3,916 victims). Among the 421 incidents of mass murder in the United States since 2000, Black, Asian, and Native American individuals were overrepresented among victims of mass shootings compared with their representation in the general U.S. population, and White individuals were underrepresented (all p ≤ .002). Findings of racial/ethnic differences were similar among victims of mass murder committed with means other than firearms for Black, Asian, and White individuals. These findings highlight different areas of victimology within the context of these incidents.
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Víctimas de Crimen , Armas de Fuego , Homicidio , Heridas por Arma de Fuego , Humanos , Estados Unidos/epidemiología , Heridas por Arma de Fuego/epidemiología , Incidentes con Víctimas en Masa , Víctimas de Crimen/estadística & datos numéricos , Grupos Raciales , EtnicidadRESUMEN
Patients at clinical high-risk (CHR) for psychosis show elevations in [18F]DOPA uptake, an estimate of dopamine (DA) synthesis capacity, in the striatum predictive of conversion to schizophrenia. Intrasynaptic DA levels can be inferred from imaging the change in radiotracer binding at D2 receptors due to a pharmacological challenge. Here, we used methylphenidate, a DA reuptake inhibitor, and [11C]-(+)-PHNO, to measure synaptic DA availability in CHR both in striatal and extra-striatal brain regions. Fourteen unmedicated, nonsubstance using CHR individuals and 14 matched control subjects participated in the study. Subjects underwent two [11C]-(+)-PHNO scans, one at baseline and one following administration of a single oral dose (60 mg) of methylphenidate. [11C]-(+)-PHNO BPND, the binding potential relative to the nondisplaceable compartment, was derived using the simplified reference tissue model with cerebellum as reference tissue. The percent change in BPND between scans, ΔBPND, was computed as an index of synaptic DA availability, and group comparisons were performed with a linear mixed model. An overall trend was found for greater synaptic DA availability (∆BPND) in CHR than controls (p = 0.06). This was driven entirely by ∆BPND in ventral striatum (-34 ± 14% in CHR, -20 ± 12% in HC; p = 0.023). There were no significant group differences in any other brain region. There were no significant differences in DA transmission in any striatal region between converters and nonconverters, although this finding is limited by the small sample size (N = 2). There was a strong and negative correlation between ΔBPND in VST and severity of negative symptoms at baseline in the CHR group (r = -0.66, p < 0.01). We show abnormally increased DA availability in the VST in CHR and an inverse relationship with negative symptoms. Our results suggest a potential early role for mesolimbic dopamine overactivity in CHR. Longitudinal studies are needed to ascertain the significance of the differential topography observed here with the [18F]DOPA literature.
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Metilfenidato , Trastornos Psicóticos , Estriado Ventral , Dopamina , Humanos , Tomografía de Emisión de Positrones , Trastornos Psicóticos/diagnóstico por imagen , Receptores de Dopamina D3/metabolismo , Estriado Ventral/diagnóstico por imagen , Estriado Ventral/metabolismoRESUMEN
Neuromelanin-sensitive MRI (NM-MRI) purports to detect the content of neuromelanin (NM), a product of dopamine metabolism that accumulates with age in dopamine neurons of the substantia nigra (SN). Interindividual variability in dopamine function may result in varying levels of NM accumulation in the SN; however, the ability of NM-MRI to measure dopamine function in nonneurodegenerative conditions has not been established. Here, we validated that NM-MRI signal intensity in postmortem midbrain specimens correlated with regional NM concentration even in the absence of neurodegeneration, a prerequisite for its use as a proxy for dopamine function. We then validated a voxelwise NM-MRI approach with sufficient anatomical sensitivity to resolve SN subregions. Using this approach and a multimodal dataset of molecular PET and fMRI data, we further showed the NM-MRI signal was related to both dopamine release in the dorsal striatum and resting blood flow within the SN. These results suggest that NM-MRI signal in the SN is a proxy for function of dopamine neurons in the nigrostriatal pathway. As a proof of concept for its clinical utility, we show that the NM-MRI signal correlated to severity of psychosis in schizophrenia and individuals at risk for schizophrenia, consistent with the well-established dysfunction of the nigrostriatal pathway in psychosis. Our results indicate that noninvasive NM-MRI is a promising tool that could have diverse research and clinical applications to investigate in vivo the role of dopamine in neuropsychiatric illness.
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Encéfalo/metabolismo , Dopamina/metabolismo , Imagen por Resonancia Magnética , Melaninas/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Femenino , Humanos , Masculino , Mesencéfalo/metabolismo , Persona de Mediana Edad , Cambios Post Mortem , Trastornos Psicóticos/diagnóstico por imagen , Reproducibilidad de los Resultados , Relación Señal-Ruido , Sustancia Negra/metabolismoRESUMEN
BACKGROUND: Early detection and intervention strategies in patients at clinical high-risk (CHR) for syndromal psychosis have the potential to contain the morbidity of schizophrenia and similar conditions. However, research criteria that have relied on severity and number of positive symptoms are limited in their specificity and risk high false-positive rates. Our objective was to examine the degree to which measures of recency of onset or intensification of positive symptoms [a.k.a., new or worsening (NOW) symptoms] contribute to predictive capacity. METHODS: We recruited 109 help-seeking individuals whose symptoms met criteria for the Progression Subtype of the Attenuated Positive Symptom Psychosis-Risk Syndrome defined by the Structured Interview for Psychosis-Risk Syndromes and followed every three months for two years or onset of syndromal psychosis. RESULTS: Forty-one (40.6%) of 101 participants meeting CHR criteria developed a syndromal psychotic disorder [mostly (80.5%) schizophrenia] with half converting within 142 days (interquartile range: 69-410 days). Patients with more NOW symptoms were more likely to convert (converters: 3.63 ± 0.89; non-converters: 2.90 ± 1.27; p = 0.001). Patients with stable attenuated positive symptoms were less likely to convert than those with NOW symptoms. New, but not worsening, symptoms, in isolation, also predicted conversion. CONCLUSIONS: Results suggest that the severity and number of attenuated positive symptoms are less predictive of conversion to syndromal psychosis than the timing of their emergence and intensification. These findings also suggest that the earliest phase of psychotic illness involves a rapid, dynamic process, beginning before the syndromal first episode, with potentially substantial implications for CHR research and understanding the neurobiology of psychosis.
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Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/psicología , Esquizofrenia/diagnóstico , Psicología del Esquizofrénico , Adolescente , Adulto , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Síntomas Prodrómicos , Escalas de Valoración Psiquiátrica , Factores de Riesgo , Síndrome , Adulto JovenRESUMEN
BACKGROUND: Mass shootings account for a small fraction of annual worldwide murders, yet disproportionately affect society and influence policy. Evidence suggesting a link between mass shootings and severe mental illness (i.e. involving psychosis) is often misrepresented, generating stigma. Thus, the actual prevalence constitutes a key public health concern. METHODS: We examined global personal-cause mass murders from 1900 to 2019, amassed by review of 14 785 murders publicly described in English in print or online, and collected information regarding perpetrator, demographics, legal history, drug use and alcohol misuse, and history of symptoms of psychiatric or neurologic illness using standardized methods. We distinguished whether firearms were or were not used, and, if so, the type (non-automatic v. semi- or fully-automatic). RESULTS: We identified 1315 mass murders, 65% of which involved firearms. Lifetime psychotic symptoms were noted among 11% of perpetrators, consistent with previous reports, including 18% of mass murderers who did not use firearms and 8% of those who did (χ2 = 28.0, p < 0.01). US-based mass shooters were more likely to have legal histories, use recreational drugs or misuse alcohol, or have histories of non-psychotic psychiatric or neurologic symptoms. US-based mass shooters with symptoms of any psychiatric or neurologic illness more frequently used semi-or fully-automatic firearms. CONCLUSIONS: These results suggest that policies aimed at preventing mass shootings by focusing on serious mental illness, characterized by psychotic symptoms, may have limited impact. Policies such as those targeting firearm access, recreational drug use and alcohol misuse, legal history, and non-psychotic psychopathology might yield more substantial results.
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BACKGROUND: The authors developed a practical and clinically useful model to predict the risk of psychosis that utilizes clinical characteristics empirically demonstrated to be strong predictors of conversion to psychosis in clinical high-risk (CHR) individuals. The model is based upon the Structured Interview for Psychosis Risk Syndromes (SIPS) and accompanying clinical interview, and yields scores indicating one's risk of conversion. METHODS: Baseline data, including demographic and clinical characteristics measured by the SIPS, were obtained on 199 CHR individuals seeking evaluation in the early detection and intervention for mental disorders program at the New York State Psychiatric Institute at Columbia University Medical Center. Each patient was followed for up to 2 years or until they developed a syndromal DSM-4 disorder. A LASSO logistic fitting procedure was used to construct a model for conversion specifically to a psychotic disorder. RESULTS: At 2 years, 64 patients (32.2%) converted to a psychotic disorder. The top five variables with relatively large standardized effect sizes included SIPS subscales of visual perceptual abnormalities, dysphoric mood, unusual thought content, disorganized communication, and violent ideation. The concordance index (c-index) was 0.73, indicating a moderately strong ability to discriminate between converters and non-converters. CONCLUSIONS: The prediction model performed well in classifying converters and non-converters and revealed SIPS measures that are relatively strong predictors of conversion, comparable with the risk calculator published by NAPLS (c-index = 0.71), but requiring only a structured clinical interview. Future work will seek to externally validate the model and enhance its performance with the incorporation of relevant biomarkers.
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Reglas de Decisión Clínica , Entrevista Psicológica , Trastornos Psicóticos/diagnóstico , Medición de Riesgo/estadística & datos numéricos , Adolescente , Adulto , Femenino , Humanos , Masculino , New York , Trastornos Psicóticos/psicología , Adulto JovenRESUMEN
The Structured Interview for Psychosis-Risk Syndromes (SIPS) contains criteria for the Attenuated Positive Symptom Syndrome (APSS), a period of subthreshold positive symptoms that predates full-blown psychosis. Motor abnormalities are often associated with these symptoms but have not been adequately studied. We assessed a diverse sample of 192 APSS participants (27.1% female; 47.9% white; mean age = 20.03 years) for motor dysfunction (SIPS G.3. score) at baseline and conversion to psychosis every 3 months for up to 2 years. Fifty-nine (30.7%) participants converted to psychosis. Baseline G.3. score was significantly higher among converters than nonconverters (mean difference = 0.66; t[95.929] = 2.579, p < 0.05). No significant differences in baseline G.3. were found between demographic groups or those with differential medication use. These results point to the use of G.3. as a potential predictor of psychosis among APSS individuals and potentially implicate the shared biological underpinnings of motor dysfunction in the APSS and full-blown psychotic illnesses.
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Trastornos Motores/complicaciones , Trastornos Psicóticos/etiología , Antipsicóticos/uso terapéutico , Femenino , Humanos , Entrevista Psicológica , Masculino , Síntomas Prodrómicos , Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/tratamiento farmacológico , Trastornos Psicóticos/psicología , Factores de Riesgo , Adulto JovenRESUMEN
OBJECTIVE: The rate of worldwide mass shootings increased almost 400% over the last 40 years. About 30% are followed by the perpetrator's fatal or nonfatal suicide attempt. METHOD: We examined the rate of fatal and nonfatal attempts among 528 mass shooters over the last 40 years and their relationship to detected mental illness to better understand this specific context of suicide. We collected information on U.S.-based, personal-cause mass murders that involved one or more firearms, from online sources. RESULTS: A greater proportion of mass shooters from 2000 to 2019 took or attempted to take their own lives (40.5%) compared with those from 1980 to 1999 (23.2%, p < 0.001). More than double the proportion of perpetrators who made a fatal or nonfatal suicide attempt had a history of non-psychotic psychiatric/neurologic symptoms (38.9%), compared with perpetrators who did not make a fatal or nonfatal suicide attempt (18.1%; p < 0.001). Among mass shooters who made fatal or nonfatal suicide attempts, 77 of 175 (44%) did not have any recorded psychiatric, neurologic, or substance use condition. Of the 98 mass shooters who made fatal or non-fatal suicide attempts and had a psychiatric, substance use, or neurologic condition, 41 had depressive disorders. CONCLUSION: It is possible that a lack of information about the perpetrators' mental health or suicidal ideation led to an underestimation of their prevalence. These data suggest that suicide associated with mass shootings may represent a specific context for suicide, and approaches such as psychological autopsy can help to ascertain when psychiatric illness mediates the relationship between mass shootings and suicide.
We examined 528 mass shootings.A greater proportion of mass shooters from 2000-2019 made a fatal or nonfatal suicide attempt (123/304, 40.5%) compared with mass shooters from 1980-1999 (52/224, 23.2%), χ2 = 17.3, p<.001.More than double the proportion of perpetrators who made a fatal or nonfatal suicide attempt had a history of non-psychotic psychiatric/neurologic symptoms (38.9%), compared with those who did not (18.1%; p < 0.001).Among mass shooters who made a fatal or nonfatal suicide attempt, 77 of 175 (44%) did not have any recorded psychiatric, neurologic, or substance use condition. However, it is possible that a lack of information about the perpetrators' mental health or suicidal ideation led to an underestimation of their prevalence.These results suggest that perpetrators may have considered suicide a potential outcome of such an event, and/or that the perpetrators' high levels of aggression and anger, accompanied by an impaired capacity for restraint, resulted in homicide followed by suicidal behavior.Psychological autopsies can clarify the role of psychiatric illness and more extreme aggressive traits in homicide-suicide instances of mass shootings.
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Importance: The link between psychosis and dopaminergic dysfunction is established, but no generalizable biomarkers with clear potential for clinical adoption exist. Objective: To replicate previous findings relating neuromelanin-sensitive magnetic resonance imaging (NM-MRI), a proxy measure of dopamine function, to psychosis severity in antipsychotic-free individuals in the psychosis spectrum and to evaluate the out-of-sample predictive ability of NM-MRI for psychosis severity. Design, Setting, and Participants: This cross-sectional study recruited participants from 2019 to 2023 in the New York City area (main samples) and Mexico City area (external validation sample). The main samples consisted of 42 antipsychotic-free patients with schizophrenia, 53 antipsychotic-free individuals at clinical high risk for psychosis (CHR), and 52 matched healthy controls. An external validation sample consisted of 16 antipsychotic-naive patients with schizophrenia. Main Outcomes and Measures: NM-MRI contrast within a subregion of the substantia nigra previously linked to psychosis severity (a priori psychosis region of interest [ROI]) and psychosis severity measured using the Positive and Negative Syndrome Scale (PANSS) in schizophrenia and the Structured Interview for Psychosis-Risk Syndromes (SIPS) in CHR. The cross-validated performance of linear support vector regression to predict psychosis severity across schizophrenia and CHR was assessed, and a final trained model was tested on the external validation sample. Results: Of the 163 included participants, 76 (46.6%) were female, and the mean (SD) age was 29.2 (10.4) years. In the schizophrenia sample, higher PANSS positive total scores correlated with higher mean NM-MRI contrast in the psychosis ROI (t37 = 2.24, P = .03; partial r = 0.35; 95% CI, 0.05 to 0.55). In the CHR sample, no significant association was found between higher SIPS positive total score and NM-MRI contrast in the psychosis ROI (t48 = -0.55, P = .68; partial r = -0.08; 95% CI, -0.36 to 0.23). The 10-fold cross-validated prediction accuracy of psychosis severity was above chance in held-out test data (mean r = 0.305, P = .01; mean root-mean-square error [RMSE] = 1.001, P = .005). External validation prediction accuracy was also above chance (r = 0.422, P = .046; RMSE = 0.882, P = .047). Conclusions and Relevance: This study provided a direct ROI-based replication of the in-sample association between NM-MRI contrast and psychosis severity in antipsychotic-free patients with schizophrenia. In turn, it failed to replicate such association in CHR individuals. Most critically, cross-validated machine-learning analyses provided a proof-of-concept demonstration that NM-MRI patterns can be used to predict psychosis severity in new data, suggesting potential for developing clinically useful tools.
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Antipsicóticos , Melaninas , Trastornos Psicóticos , Humanos , Femenino , Adulto , Masculino , Antipsicóticos/uso terapéutico , Estudios Transversales , Trastornos Psicóticos/tratamiento farmacológico , Imagen por Resonancia Magnética , DopaminaRESUMEN
While mass murders involving academic settings, especially using firearms, are of grave, growing public concern, identifying consistent patterns to aid prevention has proved challenging. Although some characteristics, such as male sex, have been routinely associated with these events, another hypothesized risk factor, severe mental illness, has been less reliably predictive. We isolated cases of mass murder perpetrated at least in part at schools, colleges, and universities from the Columbia Mass Murder Database (CMDD) and categorized them by location (within or outside of the US), and whether firearms were used. Demographic similarities and differences between groups were analyzed statistically wherever possible. We examined 82 incidents of mass murder, by any means, involving academic settings. Nearly half of all incidents (47.6%), and most involving firearms (63.2%), were U.S.-based, whereas those not involving firearms largely occurred elsewhere (88.0%). Consistent with previous reports, perpetrators of mass shootings involving academic settings are primarily Caucasian (66.7%) and male (100%). Severe mental illness (i.e., psychosis) was absent in the majority of perpetrators (firearms: 80.7%; nonfirearms: 68.0%). About half (45.6%) of mass school shootings ended with the perpetrator's suicide. When present, psychotic symptoms are more associated with mass murders in academic settings involving means other than firearms. The question of whether perpetrators of such incidents may perceive their actions as a kind of final act might enhance policy development and/or how law enforcement intervenes.
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Armas de Fuego , Incidentes con Víctimas en Masa , Humanos , Masculino , Universidades , Homicidio , Instituciones AcadémicasRESUMEN
BACKGROUND: Local gyrification index (lGI), indicative of the degree of cortical folding is a proxy marker for early cortical neurodevelopmental abnormalities. We studied the difference in lGI between those who do and do not convert to psychosis (non-converters) in a clinical high-risk (CHR) cohort, and whether lGI predicts conversion to psychosis. METHODS: Seventy-two CHR participants with attenuated positive symptom syndrome were followed up for two years. The difference in baseline whole-brain lGI was examined on the T1-weighted MRIs between, i)CHR (N = 72) and healthy controls (N = 19), ii)Converters to psychosis (N = 24) and non-converters (N = 48), adjusting for age and sex, on Freesurfer-6.0. The significant cluster obtained in the converters versus non-converters comparison was registered as a region of interest to individual images of all 72 participants and lGI values were extracted from this region. A cox proportional hazards model was applied with these values to study whether lGI predicts conversion to psychosis. RESULTS: lGI was not different between CHR and healthy controls. lGI was increased in converters in the right-sided inferior parietal and lateral occipital areas (corrected cluster-wise-p-value = 0.009, cohen's f = 0.42) compared to non-converters, which significantly increased the risk of onset of psychosis (p = 0.029, hazard ratio = 1.471). CONCLUSIONS: Increased gyrification in the right-sided inferior parietal and lateral occipital area differentiates converters to psychosis in CHR, significantly increasing the risk of conversion to psychosis. This measure may reflect underlying traits in parts of the brain that develop earliest in-utero (parietal and occipital), conferring a heightened vulnerability to convert to syndromal psychosis subsequently.
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Imagen por Resonancia Magnética , Trastornos Psicóticos , Humanos , Trastornos Psicóticos/diagnóstico por imagen , Lóbulo Occipital/diagnóstico por imagen , Encéfalo , Síndrome , Corteza CerebralRESUMEN
Background: Schizophrenia (SCZ) is marked by working memory (WM) deficits, which predict poor functional outcome. While most functional magnetic resonance imaging studies of WM in SCZ have focused on the dorsolateral prefrontal cortex (PFC), some recent work suggests that the medial PFC (mPFC) may play a role. We investigated whether task-evoked mPFC deactivation is associated with WM performance and whether it mediates deficits in SCZ. In addition, we investigated associations between mPFC deactivation and cortical dopamine release. Methods: Patients with SCZ (n = 41) and healthy control participants (HCs) (n = 40) performed a visual object n-back task during functional magnetic resonance imaging. Dopamine release capacity in mPFC was quantified with [11C]FLB457 in a subset of participants (9 SCZ, 14 HCs) using an amphetamine challenge. Correlations between task-evoked deactivation and performance were assessed in mPFC and dorsolateral PFC masks and were further examined for relationships with diagnosis and dopamine release. Results: mPFC deactivation was associated with WM task performance, but dorsolateral PFC activation was not. Deactivation in the mPFC was reduced in patients with SCZ relative to HCs and mediated the relationship between diagnosis and WM performance. In addition, mPFC deactivation was significantly and inversely associated with dopamine release capacity across groups and in HCs alone, but not in patients. Conclusions: Reduced WM task-evoked mPFC deactivation is a mediator of, and potential substrate for, WM impairment in SCZ, although our study design does not rule out the possibility that these findings could relate to cognition in general rather than WM specifically. We further present preliminary evidence of an inverse association between deactivation during WM tasks and dopamine release capacity in the mPFC.
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Mass murder, particularly mass shootings, constitutes a major, growing public health concern. Specific motivations for these acts are not well understood, often overattributed to severe mental illness. Identifying diverse factors motivating mass murders may facilitate prevention. We examined 1,725 global mass murders from 1900-2019, publicly described in English in print or online. We empirically categorized each into one of ten categories reflecting reported primary motivating factors, which were analyzed across mass murderers generally, as well as between U.S- and non-U.S.-based mass-shooters. Psychosis or disorganization related to mental illness were infrequently motivational factors (166; 9.6%), and were significantly more associated with mass murder committed using methods other than firearms. The vast majority (998, 57.86%) of incidents were impulsive and emotionally-driven, following adverse life circumstances. Most mass murderers prompted by emotional upset were found to be driven by despair or extreme sadness over life events (161, 16.13% within the category); romantic rejection or loss, or severe jealousy (204, 20.44% within the category); some specific non-romantic grudge (212, 21.24% within the category); or explosive, overwhelming rage following a dispute (266, 26.65% within the category). Results suggest that policies seeking to prevent mass murder should focus on criminal history, as well as subacute emotional disturbances not associated with severe mental illness in individuals with poor coping skills who have recently experienced negative life events.
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BACKGROUND: Patients with schizophrenia show reduced NMDA glutamate receptor-dependent auditory plasticity, which is rate limiting for auditory cognitive remediation (AudRem). We evaluate the utility of behavioral and neurophysiological pharmacodynamic target engagement biomarkers, using a d-serine+AudRem combination. METHODS: Forty-five participants with schizophrenia or schizoaffective disorder were randomized to 3 once-weekly AudRem visits + double-blind d-serine (80, 100, or 120 mg/kg) or placebo in 3 dose cohorts of 12 d-serine and 3 placebo-treated participants each. In AudRem, participants indicated which paired tone was higher in pitch. The primary outcome was plasticity improvement, operationalized as change in pitch threshold between AudRem tones [(test tone Hz - reference tone Hz)/reference tone Hz] between the initial plateau pitch threshold (mean of trials 20-30 of treatment visit 1) to pitch threshold at the end of visit(s). Target engagement was assessed by electroencephalography outcomes, including mismatch negativity (pitch primary). RESULTS: There was a significant overall treatment effect for plasticity improvement (p = .014). Plasticity improvement was largest within the 80 and 100 mg/kg groups (p < .001, d > 0.67), while 120 mg/kg and placebo-treated participants showed nonsignificant within-group changes. Plasticity improvement was seen after a single treatment and was sustained on subsequent treatments. Target engagement was demonstrated by significantly larger mismatch negativity (p = .049, d = 1.0) for the 100 mg/kg dose versus placebo. CONCLUSIONS: Our results demonstrate sufficient proof of principle for continued development of both the d-serine+AudRem combination and our target engagement methodology. The ultimate utility is dependent on the results of an ongoing larger, longer study of the combination for clinically relevant outcomes.
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Antipsicóticos , Esquizofrenia , Humanos , Esquizofrenia/tratamiento farmacológico , Serina , Receptores de N-Metil-D-Aspartato , N-Metilaspartato/farmacología , N-Metilaspartato/uso terapéutico , Agonistas de Aminoácidos Excitadores/farmacología , Agonistas de Aminoácidos Excitadores/uso terapéutico , Ácido Glutámico/farmacología , Método Doble Ciego , Plasticidad Neuronal , Antipsicóticos/uso terapéuticoRESUMEN
Self-stigma has been associated with reduced accuracy of face emotion recognition in individuals at clinical high risk for psychosis (CHR). Stigma may also relate to slowing of performance during cognitive tasks for which a negative stereotype is relevant. This study aimed to investigate the association of mental illness stigma with face emotion recognition among CHR individuals. Participants were 143 CHR individuals identified using the Structured Interview for Psychosis-Risk Syndromes (SIPS). Face emotion recognition was assessed using the Penn Emotion Recognition Task (ER-40). Stigma was assessed using discrimination, stereotype awareness, and stereotype agreement subscales of the Mental Health Attitudes Interview for CHR. We tested associations of ER-40 accuracy and response times with these stigma variables, including the role of clinical and demographic factors. Racial/ethnic minoritized participants had higher attenuated positive symptoms than non-minoritized participants. Longer ER-40 response times were correlated with greater stereotype agreement (r=.17, p=.045) and discrimination (r=.22, p=.012). A regression model predicting ER-40 response times revealed an interaction of stereotype agreement with minoritized status (p=.008), with slower response times for minoritized participants as stereotype agreement increased. Greater disorganized symptoms and male gender also predicted longer response times. ER-40 accuracy was not associated with stigma. Overall, minoritized CHR individuals with greater internalized stigma took longer to identify face emotions. Future research is needed to assess whether slower response times are specific to social cues, and if internalized stigma interferes with performance in real-world social situations. Reducing stigma may be an important target for interventions that aim to improve social skills.
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The phenotype of schizophrenia, regardless of etiology, represents the most studied psychotic disorder with respect to neurobiology and distinct phases of illness. The early phase of illness represents a unique opportunity to provide effective and individualized interventions that can alter illness trajectories. Developmental age and illness stage, including temporal variation in neurobiology, can be targeted to develop phase-specific clinical assessment, biomarkers, and interventions. We review an earlier model whereby an initial glutamate signaling deficit progresses through different phases of allostatic adaptation, moving from potentially reversible functional abnormalities associated with early psychosis and working memory dysfunction, and ending with difficult-to-reverse structural changes after chronic illness. We integrate this model with evidence of dopaminergic abnormalities, including cortical D1 dysfunction, which develop during adolescence. We discuss how this model and a focus on a potential critical window of intervention in the early stages of schizophrenia impact the approach to research design and clinical care. This impact includes stage-specific considerations for symptom assessment as well as genetic, cognitive, and neurophysiological biomarkers. We examine how phase-specific biomarkers of illness phase and brain development can be incorporated into current strategies for large-scale research and clinical programs implementing coordinated specialty care. We highlight working memory and D1 dysfunction as early treatment targets that can substantially affect functional outcome.
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AIM: The experiences of culturally diverse individuals at clinical high-risk for psychosis (CHR) is not well studied. Exploratory research needs to examine whether differences exist between racial/ethnic groups within the CHR population. Understanding experiences of Latinx patients is of importance, as the Latinx population represents the most rapidly growing paediatric population in the United States and they face significant barriers to mental health treatment. Because Latinx persons experience high rates of mental illness-based stigma and discrimination in their communities, they may face additional stigma-based barriers to CHR treatment. METHOD: Twenty-six participants (15 Latinx, 11 non-Latinx white/NLW) who met CHR criteria based on the Structured Interview for Psychosis-Risk Syndromes (SIPS) were interviewed regarding stigma associated with CHR identification and symptoms. Using a consensus-based open-coding thematic analysis approach, data were analysed for stigma, discrimination, and coping responses. RESULTS: Instances of internalization of stereotypes appeared to be more salient to NLW participants than Latinx participants, and Latinx participants reported seemingly more anticipated rejection from stereotypes than NLW participants. Experiences of discrimination also appeared to be more salient to Latinx participants than NLW participants. Moreover, Latinx participants reported evidently greater instances of discrimination across anticipated, individual, and structural discrimination. Finally, while covering strategies appeared to be more salient to NLW's, Latinx clients more often described using secrecy as well as a greater range of coping responses, including empowerment. CONCLUSION: While the experience of anticipated rejection appeared to be more salient to Latinx CHR participants and they seemingly report more secrecy than NLW, they also engaged in empowerment-related coping strategies. Future research should continue to explore the roles of cultural values in influencing coping strategies among CHR individuals.
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Trastornos Psicóticos , Estigma Social , Adaptación Psicológica , Niño , Etnicidad , Humanos , Trastornos Psicóticos/psicología , Estados UnidosRESUMEN
Objective: Some adverse cannabis effects are greater in individuals on the psychosis spectrum compared to healthy individuals. We have previously reported that smoked cannabis acutely worsened psychotic- like states and reduced cognitive performance selectively in cannabis users at clinical high-risk (CHR) for psychosis. The objective of the present study was to further investigate the acute effects of cannabis on cognition and reward processing in CHR cannabis users. Methods: Six CHR cannabis users and six psychiatrically-healthy cannabis users comparable in intellectual, demographic, and cannabis use characteristics (including nontreatment-seeking status), participated in the study. Objective and subjective measures of cognition and cannabis reward, were completed before and after smoking half of an active (5.5% Δ9tetrahydrocannabinol [Δ9-THC]) or half of a placebo (0.0% Δ9-THC) cannabis cigarette, under randomized/double-blind conditions. Repeated measures ANOVA tested main effects of drug condition (active vs. placebo) and/or the drug condition × time (baseline vs. post-administration) interactions; groups were analyzed separately due to the small sample size. Results: CHR participants exhibited evidence of decreased objective response inhibition and aversive intoxication following active cannabis, relative to placebo. Psychomotor speed and cannabis-related attentional bias were also affected by cannabis intoxication. No such effects were observed in psychiatrically-healthy cannabis users. Conclusion: These findings provide further preliminary evidence of a deleterious cognitive and reward- related response to cannabis in individuals with preexisting risk for psychosis.
RESUMEN
BACKGROUND: The differential effects of so-called 'first- and second generation' antipsychotic medications, when given in the first episode, on the long-term outcome of schizophrenia remain to be elucidated. AIMS: We compared the 9-year outcomes of individuals initially randomised to clozapine or chlorpromazine. METHOD: One-hundred and sixty individuals with treatment-naive, first episode schizophrenia or schizophreniform disorder in a mental health centre in Beijing, China were randomised to clozapine or chlorpromazine treatment for up to 2 years,followed by up to an additional 7 years of naturalistic treatment. The primary outcome was remission status for individuals in each group. RESULTS: Individuals in both groups spent essentially equal amounts of time in each clinical state over the follow-up time period(remission, 78%; intermediate, 8%; relapse, 14%). There were no significant differences on other measures of illness severity. The clozapine group was more likely than the chlorpromazine group to remain on the medication to which they were originally assigned (26% v. 10%, P = 0.01). There were no significant differences between the two groups on other secondary efficacy outcomes. CONCLUSIONS: These findings support the comparability in effectiveness between antipsychotic medications but with slightly greater tolerability of clozapine in the treatment of first-episode psychosis.