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1.
Brain Behav Immun ; 117: 70-79, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38169244

RESUMEN

BACKGROUND: Choroid plexus (ChP) enlargement exists in first-episode and chronic psychosis, but whether enlargement occurs before psychosis onset is unknown. This study investigated whether ChP volume is enlarged in individuals with clinical high-risk (CHR) for psychosis and whether these changes are related to clinical, neuroanatomical, and plasma analytes. METHODS: Clinical and neuroimaging data from the North American Prodrome Longitudinal Study 2 (NAPLS2) was used for analysis. 509 participants (169 controls, 340 CHR) were recruited. Conversion status was determined after 2-years of follow-up, with 36 psychosis converters. The lateral ventricle ChP was manually segmented from baseline scans. A subsample of 31 controls and 53 CHR had plasma analyte and neuroimaging data. RESULTS: Compared to controls, CHR (d = 0.23, p = 0.017) and non-converters (d = 0.22, p = 0.03) demonstrated higher ChP volumes, but not in converters. In CHR, greater ChP volume correlated with lower cortical (r = -0.22, p < 0.001), subcortical gray matter (r = -0.21, p < 0.001), and total white matter volume (r = -0.28,p < 0.001), as well as larger lateral ventricle volume (r = 0.63,p < 0.001). Greater ChP volume correlated with makers functionally associated with the lateral ventricle ChP in CHR [CCL1 (r = -0.30, p = 0.035), ICAM1 (r = 0.33, p = 0.02)], converters [IL1ß (r = 0.66, p = 0.004)], and non-converters [BMP6 (r = -0.96, p < 0.001), CALB1 (r = -0.98, p < 0.001), ICAM1 (r = 0.80, p = 0.003), SELE (r = 0.59, p = 0.026), SHBG (r = 0.99, p < 0.001), TNFRSF10C (r = 0.78, p = 0.001)]. CONCLUSIONS: CHR and non-converters demonstrated significantly larger ChP volumes compared to controls. Enlarged ChP was associated with neuroanatomical alterations and analyte markers functionally associated with the ChP. These findings suggest that the ChP may be a key an important biomarker in CHR.


Asunto(s)
Plexo Coroideo , Trastornos Psicóticos , Humanos , Plexo Coroideo/diagnóstico por imagen , Estudios Longitudinales , Fenotipo , Trastornos Psicóticos/diagnóstico por imagen , Neuroimagen
2.
Psychol Med ; 53(7): 2946-2953, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35094733

RESUMEN

BACKGROUND: Numerous theories posit different core features to borderline personality disorder (BPD). Recent advances in network analysis provide a method of examining the relative centrality of BPD symptoms, as well as examine the replicability of findings across samples. Additionally, despite the increase in research supporting the validity of BPD in adolescents, clinicians are reluctant to diagnose BPD in adolescents. Establishing the replicability of the syndrome across adolescents and adults informs clinical practice and research. This study examined the stability of BPD symptom networks and centrality of symptoms across samples varying in age and clinical characteristics. METHODS: Cross-sectional analyses of BPD symptoms from semi-structured diagnostic interviews from the Collaborative Longitudinal Study of Personality Disorders (CLPS), the Methods to Improve Diagnostic Assessment and Service (MIDAS) study, and an adolescent clinical sample. Network attributes, including edge (partial association) strength and node (symptom) expected influence, were compared. RESULTS: The three networks were largely similar and strongly correlated. Affective instability and identity disturbance emerged as relatively central symptoms across the three samples, and relationship difficulties across adult networks. Differences in network attributes were more evident between networks varying both in age and in BPD symptom severity level. CONCLUSIONS: Findings highlight the relative importance of affective, identity, and relationship symptoms, consistent with several leading theories of BPD. The network structure of BPD symptoms appears generally replicable across multiple large samples including adolescents and adults, providing further support for the validity of the diagnosis across these developmental phases.


Asunto(s)
Trastorno de Personalidad Limítrofe , Humanos , Adulto , Adolescente , Trastorno de Personalidad Limítrofe/diagnóstico , Trastorno de Personalidad Limítrofe/psicología , Estudios Longitudinales , Estudios Transversales , Manual Diagnóstico y Estadístico de los Trastornos Mentales , Emociones
3.
Psychol Med ; 53(6): 2399-2408, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-37144963

RESUMEN

BACKGROUND: To what extent psychotic symptoms in first-episode psychosis (FEP) with a history of childhood interpersonal trauma (CIT) are less responsive to antipsychotic medication is not known. In this longitudinal study, we compare symptom trajectories and remission over the first 2 years of treatment in FEP with and without CIT and examine if differences are linked to the use of antipsychotics. METHODS: FEP (N = 191) were recruited from in- and outpatient services 1997-2000, and assessed at baseline, 3 months, 1 and 2 years. Inclusion criteria were 15-65 years, actively psychotic with a DSM-IV diagnosis of psychotic disorder and no previous adequate treatment for psychosis. Antipsychotic medication is reported as defined daily dosage (DDD). CIT (<18) was assessed with the Brief Betrayal Trauma Survey, and symptomatic remission based on scores from the Positive and Negative Syndrome Scale. RESULTS: CIT (n = 63, 33%) was not associated with symptomatic remission at 2 years follow-up (71% in remission, 14% in relapse), or time to first remission (CIT 12/ no-CIT 9 weeks, p = 0.51). Those with CIT had significantly more severe positive, depressive, and excited symptoms. FEP with physical (N = 39, 20%) or emotional abuse (N = 22, 14, 7%) had higher DDD at 1 year (p < 0.05). Mean DDD did not excerpt a significant between-group effect on symptom trajectories of positive symptoms. CONCLUSION: Results indicate that antipsychotic medication is equally beneficial in the achievement of symptomatic remission in FEP after 2 years independent of CIT. Still, FEP patients with CIT had more severe positive, depressive, and excited symptoms throughout.


Asunto(s)
Experiencias Adversas de la Infancia , Antipsicóticos , Trastornos Psicóticos , Humanos , Antipsicóticos/uso terapéutico , Estudios Longitudinales , Trastornos Psicóticos/psicología
4.
Soc Psychiatry Psychiatr Epidemiol ; 58(4): 559-568, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36348056

RESUMEN

PURPOSE: Migrant status is a known risk factor for psychosis, but the underlying causes of this vulnerability are poorly understood. Recently, studies have begun to explore whether migrant status predicts transition to psychosis in individuals at clinical high risk (CHR) for psychosis. Results, however, have been inconclusive. The present study assessed the impact of migrant status on clinical symptoms and functional outcome in individuals at CHR for psychosis who took part in the NAPLS-3 study. METHODS: Participants' migrant status was classified as native-born, first-generation, or second-generation migrant. Clinical symptoms were assessed using the Structured Interview for Psychosis-Risk Syndromes (SIPS); functional outcome was measured using the Global Functioning Scales:Social and Role (GF:S; GF:R). Assessments were conducted at baseline, 12-months, 18-months, and 24-months follow-up. Generalized linear mixed models for repeated measures were used to examine changes over time and differences between groups. RESULTS: The overall sample included 710 individuals at CHR for psychosis (54.2% males; Age: M = 18.19; SD = 4.04). A mixed model analysis was conducted, and no significant differences between groups in symptoms or functioning were observed at any time point. Over time, significant improvement in symptoms and functioning was observed within each group. Transition rates did not differ across groups. CONCLUSION: We discuss potential factors that might explain the lack of group differences. Overall, migrants are a heterogeneous population. Discerning the impact of migration from that of neighborhood ethnic density, social disadvantage or socio-economic status of different ethnic groups could help better understand vulnerability and resilience to psychosis.


Asunto(s)
Trastornos Psicóticos , Migrantes , Masculino , Humanos , Adolescente , Femenino , Estudios Longitudinales , Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/epidemiología , Factores de Riesgo , Síntomas Prodrómicos
5.
Mol Psychiatry ; 26(11): 6833-6844, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34024906

RESUMEN

Subtle alterations in white matter microstructure are observed in youth at clinical high risk (CHR) for psychosis. However, the timing of these changes and their relationships to the emergence of psychosis remain unclear. Here, we track the evolution of white matter abnormalities in a large, longitudinal cohort of CHR individuals comprising the North American Prodrome Longitudinal Study (NAPLS-3). Multi-shell diffusion magnetic resonance imaging data were collected across multiple timepoints (1-5 over 1 year) in 286 subjects (aged 12-32 years): 25 CHR individuals who transitioned to psychosis (CHR-P; 61 scans), 205 CHR subjects with unknown transition outcome after the 1-year follow-up period (CHR-U; 596 scans), and 56 healthy controls (195 scans). Linear mixed effects models were fitted to infer the impact of age and illness-onset on variation in the fractional anisotropy of cellular tissue (FAT) and the volume fraction of extracellular free water (FW). Baseline measures of white matter microstructure did not differentiate between HC, CHR-U and CHR-P individuals. However, age trajectories differed between the three groups in line with a developmental effect: CHR-P and CHR-U groups displayed higher FAT in adolescence, and 4% lower FAT by 30 years of age compared to controls. Furthermore, older CHR-P subjects (20+ years) displayed 4% higher FW in the forceps major (p < 0.05). Prospective analysis in CHR-P did not reveal a significant impact of illness onset on regional FAT or FW, suggesting that transition to psychosis is not marked by dramatic change in white matter microstructure. Instead, clinical high risk for psychosis-regardless of transition outcome-is characterized by subtle age-related white matter changes that occur in tandem with development.


Asunto(s)
Trastornos Psicóticos , Sustancia Blanca , Adolescente , Adulto , Niño , Preescolar , Cuerpo Calloso/patología , Humanos , Estudios Longitudinales , Síntomas Prodrómicos , Trastornos Psicóticos/patología , Sustancia Blanca/patología , Adulto Joven
6.
BMC Psychiatry ; 22(1): 784, 2022 12 13.
Artículo en Inglés | MEDLINE | ID: mdl-36514073

RESUMEN

OBJECTIVE: The Mini-SIPS, a condensed version of the Structured Interview for Psychosis-Risk Syndromes (SIPS), is intended to efficiently identify for clinicians the minimum information needed to support a DSM-5 Attenuated Psychosis Syndrome (APS) diagnosis. METHODS: The instrument and the DSM-5 criteria are accessible through the online training program. RESULTS: Most individuals (67.5%) in the first 212 to complete the training program indicated an intended use of the Mini-SIPS exclusively for clinical purposes. Performance on the post-training quiz was excellent for those with and without prior training in structured diagnostic interviewing. CONCLUSION: The Mini-SIPS, and accompanying training program, are offered as public-domain clinical resources to the mental health community.


Asunto(s)
Síntomas Prodrómicos , Trastornos Psicóticos , Humanos , Síndrome , Trastornos Psicóticos/diagnóstico , Manual Diagnóstico y Estadístico de los Trastornos Mentales
7.
Soc Psychiatry Psychiatr Epidemiol ; 57(7): 1379-1388, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35113189

RESUMEN

PURPOSE: Bullying is associated with a heightened risk for poor outcomes, including psychosis. This study aimed to replicate previous findings on bullying prevalence in clinical high-risk (CHR) individuals, to assess the longitudinal course of clinical and functional variables between bullied and non-bullied CHR and the association of bullying with premorbid functioning, clinical outcome, transition to psychosis and risk of violence. METHODS: The sample consisted of 691 CHR participants and 96 healthy controls. Participants reported whether they had experienced bullying and how long it had lasted. Assessments included DSM-5 diagnoses, attenuated psychotic symptoms, negative symptoms, social and role functioning, depression, stress, premorbid functioning, and risk of violence. The bullied and non-bullied CHR groups were compared at baseline and further longitudinally on clinical and functioning variables and transition to psychosis. RESULTS: Bullying was more prevalent among CHR individuals than healthy controls. Bullied CHR had a higher prevalence of PTSD and more severe depression and stress at baseline than non-bullied CHR. There was no impact of bullying on clinical and functional variables over time. Bullying was not related to final clinical status or transition to psychosis. However, bullied participants had poorer premorbid functioning and a greater risk of violence. CONCLUSION: While bullying may not impact the likelihood of CHR individuals to transition to psychosis, it may be a risk factor for development of the at-risk state and may be related to a greater risk of violence. Future studies should consider bullying perpetration among CHR individuals.


Asunto(s)
Acoso Escolar , Trastornos Psicóticos , Estudios de Cohortes , Humanos , Síntomas Prodrómicos , Trastornos Psicóticos/complicaciones , Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/epidemiología , Factores de Riesgo
8.
Soc Psychiatry Psychiatr Epidemiol ; 56(6): 943-952, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33399885

RESUMEN

PURPOSE: Migrant status is one of the most replicated and robust risk factors for developing a psychotic disorder. This study aimed to determine whether migrant status in people identified as Ultra-High Risk for Psychosis (UHR) was associated with risk of transitioning to a full-threshold psychotic disorder. METHODS: Hazard ratios for the risk of transition were calculated from five large UHR cohorts (n = 2166) and were used to conduct a meta-analysis using the generic inverse-variance method using a random-effects model. RESULTS: 2166 UHR young people, with a mean age of 19.1 years (SD ± 4.5) were included, of whom 221 (10.7%) were first-generation migrants. A total of 357 young people transitioned to psychosis over a median follow-up time of 417 days (I.Q.R.147-756 days), representing 17.0% of the cohort. The risk of transition to a full-threshold disorder was not increased for first-generation migrants, (HR = 1.08, 95% CI 0.62-1.89); however, there was a high level of heterogeneity between studies The hazard ratio for second-generation migrants to transition to a full-threshold psychotic disorder compared to the remainder of the native-born population was 1.03 (95% CI 0.70-1.51). CONCLUSIONS: This meta-analysis did not find a statistically significant association between migrant status and an increased risk for transition to a full-threshold psychotic disorder; however, several methodological issues could explain this finding. Further research should focus on examining the risk of specific migrant groups and also ensuring that migrant populations are adequately represented within UHR clinics.


Asunto(s)
Trastornos Psicóticos , Migrantes , Adolescente , Adulto , Estudios de Cohortes , Humanos , Modelos de Riesgos Proporcionales , Escalas de Valoración Psiquiátrica , Trastornos Psicóticos/epidemiología , Factores de Riesgo , Adulto Joven
9.
Cereb Cortex ; 29(3): 1263-1279, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29522112

RESUMEN

While graph theoretical modeling has dramatically advanced our understanding of complex brain systems, the feasibility of aggregating connectomic data in large imaging consortia remains unclear. Here, using a battery of cognitive, emotional and resting fMRI paradigms, we investigated the generalizability of functional connectomic measures across sites and sessions. Our results revealed overall fair to excellent reliability for a majority of measures during both rest and tasks, in particular for those quantifying connectivity strength, network segregation and network integration. Processing schemes such as node definition and global signal regression (GSR) significantly affected resulting reliability, with higher reliability detected for the Power atlas (vs. AAL atlas) and data without GSR. While network diagnostics for default-mode and sensori-motor systems were consistently reliable independently of paradigm, those for higher-order cognitive systems were reliable predominantly when challenged by task. In addition, based on our present sample and after accounting for observed reliability, satisfactory statistical power can be achieved in multisite research with sample size of approximately 250 when the effect size is moderate or larger. Our findings provide empirical evidence for the generalizability of brain functional graphs in large consortia, and encourage the aggregation of connectomic measures using multisite and multisession data.


Asunto(s)
Encéfalo/fisiología , Conectoma , Emociones/fisiología , Imagen por Resonancia Magnética , Memoria/fisiología , Adulto , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Masculino , Memoria Episódica , Memoria a Corto Plazo/fisiología , Recuerdo Mental/fisiología , Vías Nerviosas/fisiología , Pruebas Neuropsicológicas , Adulto Joven
10.
Dev Psychopathol ; 32(1): 343-356, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-30846020

RESUMEN

Childhood adversity is associated with poor mental and physical health outcomes across the life span. Alterations in the hypothalamic-pituitary-adrenal axis are considered a key mechanism underlying these associations, although findings have been mixed. These inconsistencies suggest that other aspects of stress processing may underlie variations in this these associations, and that differences in adversity type, sex, and age may be relevant. The current study investigated the relationship between childhood adversity, stress perception, and morning cortisol, and examined whether differences in adversity type (generalized vs. threat and deprivation), sex, and age had distinct effects on these associations. Salivary cortisol samples, daily hassle stress ratings, and retrospective measures of childhood adversity were collected from a large sample of youth at risk for serious mental illness including psychoses (n = 605, mean age = 19.3). Results indicated that childhood adversity was associated with increased stress perception, which subsequently predicted higher morning cortisol levels; however, these associations were specific to threat exposures in females. These findings highlight the role of stress perception in stress vulnerability following childhood adversity and highlight potential sex differences in the impact of threat exposures.


Asunto(s)
Sistema Hipotálamo-Hipofisario/fisiopatología , Trastornos Mentales/fisiopatología , Sistema Hipófiso-Suprarrenal/fisiopatología , Estrés Psicológico/fisiopatología , Adolescente , Adulto , Factores de Edad , Niño , Femenino , Humanos , Hidrocortisona/análisis , Masculino , Estudios Retrospectivos , Saliva/química , Caracteres Sexuales , Factores Sexuales , Adulto Joven
11.
Psychol Med ; 49(10): 1670-1677, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30176955

RESUMEN

BACKGROUND: Much of the interest in youth at clinical high risk (CHR) of psychosis has been in understanding conversion. Recent literature has suggested that less than 25% of those who meet established criteria for being at CHR of psychosis go on to develop a psychotic illness. However, little is known about the outcome of those who do not make the transition to psychosis. The aim of this paper was to examine clinical symptoms and functioning in the second North American Prodrome Longitudinal Study (NAPLS 2) of those individuals whose by the end of 2 years in the study had not developed psychosis. METHODS: In NAPLS-2 278 CHR participants completed 2-year follow-ups and had not made the transition to psychosis. At 2-years the sample was divided into three groups - those whose symptoms were in remission, those who were still symptomatic and those whose symptoms had become more severe. RESULTS: There was no difference between those who remitted early in the study compared with those who remitted at one or 2 years. At 2-years, those in remission had fewer symptoms and improved functioning compared with the two symptomatic groups. However, all three groups had poorer social functioning and cognition than healthy controls. CONCLUSIONS: A detailed examination of the clinical and functional outcomes of those who did not make the transition to psychosis did not contribute to predicting who may make the transition or who may have an earlier remission of attenuated psychotic symptoms.


Asunto(s)
Progresión de la Enfermedad , Síntomas Prodrómicos , Trastornos Psicóticos/epidemiología , Adolescente , Adulto , Femenino , Humanos , Estudios Longitudinales , Masculino , América del Norte/epidemiología , Remisión Espontánea , Riesgo , Adulto Joven
12.
Brain Behav Immun ; 76: 268-274, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30496778

RESUMEN

Negative symptoms are common in individuals at clinical high-risk (CHR) for psychosis and are associated with worse functional outcomes. Inflammation may be one mechanism underlying negative symptoms. Inflammatory markers are altered in individuals at CHR and are associated with negative symptoms in patients with schizophrenia. We thus hypothesized that baseline inflammatory markers would predict the development of negative symptoms in individuals at CHR for psychosis. Thirty seven individuals from the North American Prodromal Longitudinal Study who met CHR criteria were included in the study. Inflammatory cytokines, including interferon (IFN)-λ, Interleukin (IL)-1ß, IL-1 receptor antagonist (IL-1RA), IL-4, IL-6, IL-8, IL-10, and tumor necrosis factor (TNF) were measured at baseline. Negative symptoms as measured by the Scale of Prodromal Symptoms, were measured at baseline and six and twelve months. Associations between inflammatory markers and the trajectory of negative symptoms (slope) over the first year of follow-up, were assessed using linear regression models controlling for age, sex, race and depressive symptom severity (as assessed by the Calgary Depression Scale for Schizophrenia). Baseline TNF (beta = 0.361, p = 0.007) and IL-6 (beta = -0.306, p = 0.026) predicted negative symptoms slopes, along with depressive symptom severity at baseline (beta = -0.596, p = 0.000). These findings demonstrate that inflammatory cytokines may underlie the development of negative symptoms in some individuals at CHR for psychosis. TNF predicted the development of negative symptoms independent of baseline depression. Given the heterogeneity of the CHR population, the comorbidity of negative symptoms and depression in this population, and the particular challenges in treating negative symptoms, immune markers could represent potential biomarkers that underlie the development of negative symptoms, representing a potential treatment target.


Asunto(s)
Trastornos Psicóticos/epidemiología , Trastornos Psicóticos/inmunología , Adolescente , Afecto/fisiología , Biomarcadores/sangre , Comorbilidad , Citocinas/análisis , Citocinas/sangre , Depresión/diagnóstico , Progresión de la Enfermedad , Femenino , Humanos , Inflamación/metabolismo , Inflamación/fisiopatología , Interleucina-6/sangre , Interleucina-6/metabolismo , Estudios Longitudinales , Linfotoxina-alfa/metabolismo , Masculino , Síntomas Prodrómicos , Escalas de Valoración Psiquiátrica , Factores de Riesgo , Esquizofrenia/diagnóstico , Esquizofrenia/inmunología , Esquizofrenia/fisiopatología , Adulto Joven
13.
Dev Psychopathol ; 30(1): 39-47, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28420458

RESUMEN

The developmental course of daily functioning prior to first psychosis-onset remains poorly understood. This study explored age-related periods of change in social and role functioning. The longitudinal study included youth (aged 12-23, mean follow-up years = 1.19) at clinical high risk (CHR) for psychosis (converters [CHR-C], n = 83; nonconverters [CHR-NC], n = 275) and a healthy control group (n = 164). Mixed-model analyses were performed to determine age-related differences in social and role functioning. We limited our analyses to functioning before psychosis conversion; thus, data of CHR-C participants gathered after psychosis onset were excluded. In controls, social and role functioning improved over time. From at least age 12, functioning in CHR was poorer than in controls, and this lag persisted over time. Between ages 15 and 18, social functioning in CHR-C stagnated and diverged from that of CHR-NC, who continued to improve (p = .001). Subsequently, CHR-C lagged behind in improvement between ages 21 and 23, further distinguishing them from CHR-NC (p < .001). A similar period of stagnation was apparent for role functioning, but to a lesser extent (p = .007). The results remained consistent when we accounted for the time to conversion. Our findings suggest that CHR-C start lagging behind CHR-NC in social and role functioning in adolescence, followed by a period of further stagnation in adulthood.


Asunto(s)
Trastornos Psicóticos/psicología , Ajuste Social , Adolescente , Niño , Femenino , Humanos , Estudios Longitudinales , Masculino , Adulto Joven
14.
J Clin Child Adolesc Psychol ; 47(1): 69-78, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-27705009

RESUMEN

Early intervention for psychotic disorders, a growing international priority, typically targets help-seeking populations with emerging psychotic ("positive") symptoms. We assessed the nature of and degree to which treatment of individuals at high risk for psychosis preceded or followed the onset of positive symptoms. The North American Prodrome Longitudinal Study-2 collected psychosocial treatment histories for 745 (98%) of 764 high-risk participants (M age = 18.9, 57% male, 57.5% Caucasian, 19.1% Hispanic) recruited from 8 North American communities. Similar to prior findings, 82% of participants reported psychosocial treatment prior to baseline assessment, albeit with significant variability across sites (71%-96%). Participants first received treatment a median of 1.7 years prior to the onset of a recognizable psychosis-risk syndrome. Only one fourth sought initial treatment in the year following syndrome onset. Although mean sample age differed significantly by site, age at initial treatment (M = 14.1, SD = 5.0) did not. High rates of early treatment prior to syndrome onset make sense in light of known developmental precursors to psychotic disorders but are inconsistent with the low rates of treatment retrospectively reported by first-episode psychosis samples. Findings suggest that psychosis risk studies and clinics may need to more actively recruit and engage symptomatic but non-help-seeking individuals and that community clinicians be better trained to recognize both positive and nonspecific indicators of emerging psychosis. Improved treatments for nonspecific symptoms, as well as the characteristic attenuated positive symptoms, are needed.


Asunto(s)
Trastornos Psicóticos/terapia , Adolescente , Adulto , Estudios de Cohortes , Femenino , Humanos , Estudios Longitudinales , Masculino , América del Norte/epidemiología , Trastornos Psicóticos/diagnóstico , Estudios Retrospectivos , Adulto Joven
15.
Neuroimage ; 146: 959-970, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-27746386

RESUMEN

Recent years have witnessed an increasing number of multisite MRI functional connectivity (fcMRI) studies. While multisite studies provide an efficient way to accelerate data collection and increase sample sizes, especially for rare clinical populations, any effects of site or MRI scanner could ultimately limit power and weaken results. Little data exists on the stability of functional connectivity measurements across sites and sessions. In this study, we assess the influence of site and session on resting state functional connectivity measurements in a healthy cohort of traveling subjects (8 subjects scanned twice at each of 8 sites) scanned as part of the North American Prodrome Longitudinal Study (NAPLS). Reliability was investigated in three types of connectivity analyses: (1) seed-based connectivity with posterior cingulate cortex (PCC), right motor cortex (RMC), and left thalamus (LT) as seeds; (2) the intrinsic connectivity distribution (ICD), a voxel-wise connectivity measure; and (3) matrix connectivity, a whole-brain, atlas-based approach to assessing connectivity between nodes. Contributions to variability in connectivity due to subject, site, and day-of-scan were quantified and used to assess between-session (test-retest) reliability in accordance with Generalizability Theory. Overall, no major site, scanner manufacturer, or day-of-scan effects were found for the univariate connectivity analyses; instead, subject effects dominated relative to the other measured factors. However, summaries of voxel-wise connectivity were found to be sensitive to site and scanner manufacturer effects. For all connectivity measures, although subject variance was three times the site variance, the residual represented 60-80% of the variance, indicating that connectivity differed greatly from scan to scan independent of any of the measured factors (i.e., subject, site, and day-of-scan). Thus, for a single 5min scan, reliability across connectivity measures was poor (ICC=0.07-0.17), but increased with increasing scan duration (ICC=0.21-0.36 at 25min). The limited effects of site and scanner manufacturer support the use of multisite studies, such as NAPLS, as a viable means of collecting data on rare populations and increasing power in univariate functional connectivity studies. However, the results indicate that aggregation of fcMRI data across longer scan durations is necessary to increase the reliability of connectivity estimates at the single-subject level.


Asunto(s)
Mapeo Encefálico/métodos , Encéfalo/fisiología , Imagen por Resonancia Magnética/métodos , Adulto , Femenino , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética/instrumentación , Masculino , Estudios Multicéntricos como Asunto , Vías Nerviosas/fisiología , Reproducibilidad de los Resultados , Adulto Joven
16.
Br J Psychiatry ; 208(6): 507-9, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27251688

RESUMEN

Mental health research funding priorities in high-income countries must balance longer-term investment in identifying neurobiological mechanisms of disease with shorter-term funding of novel prevention and treatment strategies to alleviate the current burden of mental illness. Prioritising one area of science over others risks reduced returns on the entire scientific portfolio.


Asunto(s)
Investigación Biomédica/economía , Salud Mental/economía , Humanos
17.
Soc Psychiatry Psychiatr Epidemiol ; 51(4): 497-503, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26851943

RESUMEN

PURPOSE: There is evidence to suggest that both early traumatic experiences and perceived discrimination are associated with later onset of psychosis. Less is known about the impact these two factors may have on conversion to psychosis in those who are at clinical high risk (CHR) of developing psychosis. The purpose of this study was to determine if trauma and perceived discrimination were predictors of conversion to psychosis. METHODS: The sample consisted of 764 individuals who were at CHR of developing psychosis and 280 healthy controls. All participants were assessed on past trauma, bullying and perceived discrimination. RESULTS: Individuals at CHR reported significantly more trauma, bullying and perceived discrimination than healthy controls. Only perceived discrimination was a predictor of later conversion to psychosis. CONCLUSIONS: Given that CHR individuals are reporting increased rates of trauma and perceived discrimination, these should be routinely assessed, with the possibility of offering interventions aimed at ameliorating the impact of past traumas as well as improving self-esteem and coping strategies in an attempt to reduce perceived discrimination.


Asunto(s)
Acoso Escolar , Trauma Psicológico/epidemiología , Trastornos Psicóticos/epidemiología , Discriminación Social/psicología , Adolescente , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Riesgo , Adulto Joven
18.
Behav Cogn Psychother ; 44(2): 203-13, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25896713

RESUMEN

BACKGROUND: Schema Theory proposes that the development of maladaptive schemas are based on a combination of memories, emotions and cognitions regarding oneself and one's relationship to others. A cognitive model of psychosis suggests that schemas are crucial to the development and persistence of psychosis. Little is known about the impact that schemas may have on those considered to be at clinical high risk (CHR) of developing psychosis. AIMS: To investigate schemas over time in a large sample of CHR individuals and healthy controls. METHOD: Sample included 765 CHR participants and 280 healthy controls. Schemas were assessed at baseline, 6 and 12 months using the Brief Core Schema Scale (BCSS). Baseline schemas were compared to 2-year clinical outcome. RESULTS: CHR participants evidenced stable and more maladaptive schemas over time compared to controls. Schemas at initial contact did not vary amongst the different clinical outcome groups at 2 years although all CHR outcome groups evidenced significantly worse schemas than healthy controls. Although there were no differences on baseline schemas between those who later transitioned to psychosis compared to those who did not, those who transitioned to psychosis had more maladaptive negative self-schemas at the time of transition. Associations between negative schemas were positively correlated with earlier abuse and bullying. CONCLUSIONS: These findings demonstrate a need for interventions that aim to improve maladaptive schemas among the CHR population. Therapies targeting self-esteem, as well as schema therapy may be important work for future studies.


Asunto(s)
Cultura , Trastornos Psicóticos/psicología , Adaptación Psicológica , Adolescente , Estudios de Casos y Controles , Cognición , Femenino , Humanos , Estudios Longitudinales , Masculino , Pruebas Neuropsicológicas , Síntomas Prodrómicos , Factores de Riesgo , Autoimagen , Encuestas y Cuestionarios , Adulto Joven
19.
Hum Brain Mapp ; 36(7): 2558-79, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25821147

RESUMEN

Multisite neuroimaging studies can facilitate the investigation of brain-related changes in many contexts, including patient groups that are relatively rare in the general population. Though multisite studies have characterized the reliability of brain activation during working memory and motor functional magnetic resonance imaging tasks, emotion processing tasks, pertinent to many clinical populations, remain less explored. A traveling participants study was conducted with eight healthy volunteers scanned twice on consecutive days at each of the eight North American Longitudinal Prodrome Study sites. Tests derived from generalizability theory showed excellent reliability in the amygdala ( Eρ2 = 0.82), inferior frontal gyrus (IFG; Eρ2 = 0.83), anterior cingulate cortex (ACC; Eρ2 = 0.76), insula ( Eρ2 = 0.85), and fusiform gyrus ( Eρ2 = 0.91) for maximum activation and fair to excellent reliability in the amygdala ( Eρ2 = 0.44), IFG ( Eρ2 = 0.48), ACC ( Eρ2 = 0.55), insula ( Eρ2 = 0.42), and fusiform gyrus ( Eρ2 = 0.83) for mean activation across sites and test days. For the amygdala, habituation ( Eρ2 = 0.71) was more stable than mean activation. In a second investigation, data from 111 healthy individuals across sites were aggregated in a voxelwise, quantitative meta-analysis. When compared with a mixed effects model controlling for site, both approaches identified robust activation in regions consistent with expected results based on prior single-site research. Overall, regions central to emotion processing showed strong reliability in the traveling participants study and robust activation in the aggregation study. These results support the reliability of blood oxygen level-dependent signal in emotion processing areas across different sites and scanners and may inform future efforts to increase efficiency and enhance knowledge of rare conditions in the population through multisite neuroimaging paradigms.


Asunto(s)
Amígdala del Cerebelo/fisiología , Corteza Cerebral/fisiología , Emociones/fisiología , Imagen por Resonancia Magnética/normas , Estudios Multicéntricos como Asunto/normas , Adolescente , Adulto , Niño , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Adulto Joven
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