Longitudinal invariance of psychotic experiences in children and adolescents: What do the data tell us?

BACKGROUND: Psychotic experiences are common in adults, adolescents, and children. While usually self-limited, they can indicate psychosis proneness when persistent. The Community Assessment of Psychic Experiences (CAPE) measures lifetime psychotic experiences in three dimensions. The 20-item subscale addressing positive symptoms (CAPE-positive) is the most widely used. No study investigated its measurement invariance across timepoints during childhood and adolescence. This step is required to conduct reliable comparisons in longitudinal studies with different age groups. METHODS: We used data from the Brazilian High-Risk Cohort, which enrolled 2511 individuals aged 6-12 years from public schools for the baseline evaluation. A 3-year follow-up assessment evaluated 1880 participants. Subjects were rated with the CAPE-positive and we performed, at each wave, a Multigroup Confirmatory Factor Analysis testing Exploratory and Confirmatory Factor Analysis models identified in a previous systematic review, to assess longitudinal invariance. RESULTS: A three-factor solution was the best fitting model, comprising Persecutory Ideation, Bizarre Experiences and Perceptual Abnormalities. The longitudinal invariance analysis of the best-fit model was unsatisfactory, achieving only the metric level of invariance. CONCLUSIONS: Our findings suggest that the CAPE-positive scale has good model fit indices for each evaluated time point individually (children and adolescents), but it is not invariant over time. Identifying which factors affect CAPE latent structure at different time points can improve our understanding of psychosis proneness and how to measure it.

Evidence for an interrelated cluster of Hallucinatory experiences in the general population: an incidence study.

BACKGROUND: Although hallucinations have been studied in terms of prevalence and its associations with psychopathology and functional impairment, very little is known about sensory modalities other than auditory (i.e. haptic, visual and olfactory), as well the incidence of hallucinations, factors predicting incidence and subsequent course. METHODS: We examined the incidence, course and risk factors of hallucinatory experiences across different modalities in two unique prospective general population cohorts in the same country using similar methodology and with three interview waves, one over the period 1996-1999 (NEMESIS) and one over the period 2007-2015 (NEMESIS-2). RESULTS: In NEMESIS-2, the yearly incidence of self-reported visual hallucinations was highest (0.33%), followed by haptic hallucinations (0.31%), auditory hallucinations (0.26%) and olfactory hallucinations (0.23%). Rates in NEMESIS-1 were similar (respectively: 0.35%, 0.26%, 0.23%, 0.22%). The incidence of clinician-confirmed hallucinations was approximately 60% of the self-reported rate. The persistence rate of incident hallucinations was around 20-30%, increasing to 40-50% for prevalent hallucinations. Incident hallucinations in one modality were very strongly associated with occurrence in another modality (median OR = 59) and all modalities were strongly associated with delusional ideation (median OR = 21). Modalities were approximately equally strongly associated with the presence of any mental disorder (median OR = 4), functioning, indicators of help-seeking and established environmental risk factors for psychotic disorder. CONCLUSIONS: Hallucinations across different modalities are a clinically relevant feature of non-psychotic disorders and need to be studied in relation to each other and in relation to delusional ideation, as all appear to have a common underlying mechanism.

Burnout syndrome and engagement among critical care providers: a cross-sectional study. / Síndrome de burnout e engajamento em profissionais de saúde: um estudo transversal.

OBJECTIVE: To evaluate the frequency of severe burnout syndrome among critical care providers and to correlate it with work engagement. METHODS: A self-administered survey including the Maslach Burnout Inventory, Depression Anxiety and Stress Scales, and Gallup questionnaire was distributed. All analyses were stratified by setting (intensive care unit or step-down unit) and by professional group (nurses versus physicians versus physiotherapists). RESULTS: Between February 2017 and June 2017, 206 out of 325 invited professionals (63.4%) answered the questionnaires. Of these, 55 were physicians (26.7%), 88 were physiotherapists (42.7%) and 63 were nurses (30.6%). The frequency of severe burnout was 34.3% (27.9 - 41.4%), and no difference was found between professional groups or settings. The frequency of severe or very severe cases of depression, anxiety or stress was 12.9%, 11.4% and 10.5%, respectively. The median (interquartile range) score observed on the Gallup questionnaire was 41 (34 - 48), and no differences were found between professional groups or settings. There was a negative correlation between burnout and work engagement (r = -0.148; p = 0.035). CONCLUSION: There is a high frequency of severe burnout among critical care providers working in the intensive care unit and step-down unit. There was a negative correlation between burnout and work engagement.

OBJETIVO: Avaliar a frequência de síndrome de burnout grave em profissionais de terapia intensiva e correlacioná-la com o engajamento com o trabalho. MÉTODOS: Foi distribuído um questionário autoaplicável que incluía o Inventário de Burnout de Maslach, a Escala de Depressão Ansiedade e Estresse e o questionário Gallup. Todas as análises foram estratificadas por local de trabalho (unidade de terapia intensiva ou unidade semi-intensiva) e por grupo profissional (enfermeiros versus médicos versus fisioterapeutas). RESULTADOS: Entre fevereiro de 2017 e junho de 2017, 206 dos 325 profissionais convidados (63,4%) responderam aos questionários. Destes, 55 eram médicos (26,7%), 88 eram fisioterapeutas (42,7%) e 63 eram enfermeiros (30,6%). A frequência de burnout grave foi de 34,3% (27,9 - 41,4%), e não se identificaram diferenças entre os grupos profissionais ou locais de trabalho. A frequência de casos graves ou muito graves de depressão, ansiedade ou estresse foi de 12,9%, 11,4% e 10,5%, respectivamente. O escore mediano (intervalo interquartil) observado pelo questionário Gallup foi 41 (34 - 48), e não se observaram diferenças entre os grupos profissionais ou locais de trabalho. Houve correlação negativa entre burnout e engajamento com o trabalho (r = -0,148; p = 0,035). CONCLUSÃO: A frequência de burnout grave foi elevada entre os profissionais de saúde que trabalham na unidade de terapia intensiva e na unidade semi-intensiva. Existe uma correlação negativa entre burnout e engajamento com o trabalho.

Síndrome de burnout e engajamento em profissionais de saúde: um estudo transversal / Burnout syndrome and engagement among critical care providers: a cross-sectional study

RESUMO Objetivo: Avaliar a frequência de síndrome de burnout grave em profissionais de terapia intensiva e correlacioná-la com o engajamento com o trabalho. Métodos: Foi distribuído um questionário autoaplicável que incluía o Inventário de Burnout de Maslach, a Escala de Depressão Ansiedade e Estresse e o questionário Gallup. Todas as análises foram estratificadas por local de trabalho (unidade de terapia intensiva ou unidade semi-intensiva) e por grupo profissional (enfermeiros versus médicos versus fisioterapeutas). Resultados: Entre fevereiro de 2017 e junho de 2017, 206 dos 325 profissionais convidados (63,4%) responderam aos questionários. Destes, 55 eram médicos (26,7%), 88 eram fisioterapeutas (42,7%) e 63 eram enfermeiros (30,6%). A frequência de burnout grave foi de 34,3% (27,9 - 41,4%), e não se identificaram diferenças entre os grupos profissionais ou locais de trabalho. A frequência de casos graves ou muito graves de depressão, ansiedade ou estresse foi de 12,9%, 11,4% e 10,5%, respectivamente. O escore mediano (intervalo interquartil) observado pelo questionário Gallup foi 41 (34 - 48), e não se observaram diferenças entre os grupos profissionais ou locais de trabalho. Houve correlação negativa entre burnout e engajamento com o trabalho (r = -0,148; p = 0,035). Conclusão: A frequência de burnout grave foi elevada entre os profissionais de saúde que trabalham na unidade de terapia intensiva e na unidade semi-intensiva. Existe uma correlação negativa entre burnout e engajamento com o trabalho.

ABSTRACT Objective: To evaluate the frequency of severe burnout syndrome among critical care providers and to correlate it with work engagement. Methods: A self-administered survey including the Maslach Burnout Inventory, Depression Anxiety and Stress Scales, and Gallup questionnaire was distributed. All analyses were stratified by setting (intensive care unit or step-down unit) and by professional group (nurses versus physicians versus physiotherapists). Results: Between February 2017 and June 2017, 206 out of 325 invited professionals (63.4%) answered the questionnaires. Of these, 55 were physicians (26.7%), 88 were physiotherapists (42.7%) and 63 were nurses (30.6%). The frequency of severe burnout was 34.3% (27.9 - 41.4%), and no difference was found between professional groups or settings. The frequency of severe or very severe cases of depression, anxiety or stress was 12.9%, 11.4% and 10.5%, respectively. The median (interquartile range) score observed on the Gallup questionnaire was 41 (34 - 48), and no differences were found between professional groups or settings. There was a negative correlation between burnout and work engagement (r = -0.148; p = 0.035). Conclusion: There is a high frequency of severe burnout among critical care providers working in the intensive care unit and step-down unit. There was a negative correlation between burnout and work engagement.

Differences Between Self-Reported Psychotic Experiences, Clinically Relevant Psychotic Experiences, and Attenuated Psychotic Symptoms in the General Population.

Purpose: Psychotic experiences in childhood (such as hearing voices or being suspicious) represent an important phenotype for early intervention. However, these experiences can be defined in several ways: self-reported psychotic experiences (SRPE) rely exclusively on the child's report, clinically validated psychotic experiences (CRPE) are based on clinical assessment, and attenuated psychotic symptoms (APS) represents a categorization to do with clinical relevance in relation to severity. Very few studies have investigated how these distinctions impact clinical and other domains. The present study aims to compare SRPE, CRPE, and APS among children and adolescents. Methods: This study is part of the Brazilian High-Risk Cohort Study for Psychiatric Disorders, in which 2,241 individuals aged 6-14 years provided self-ratings of 20 psychotic experiences using the Community Assessment of Psychic Experiences (CAPE). A trained psychologist conducted an interview to validate or reject reported experiences and to rate the presence of APS and affective flattening. In parallel, parents provided information about child mental health to an independent interviewer. We tested the association of mutually exclusive categories of non-validated SRPE (nSRPE), clinically validated PE below the threshold for APS (nCRPE), and APS (nSRPE = 33%, nCRPE = 11%, APS = 6%), with parents' information about the child's positive attributes and levels of psychopathology and psychologist assessment of blunted affect. Results: Most associations were qualitatively similar, and there was a dose-response in the strength of associations across categories, such that APS > nCRPE > nSRPE. Experiences in all three categories were associated with female sex. nSRPE were associated with overall levels of psychopathology, but to a lesser degree than nCRPE and APS. APS and nCRPE were associated with less positive attributes, with APS more so than nCRPE. Only APS was associated with affective flattening. Conclusions: In children and adolescents, SRPE, CRPE, and APS all index liability for psychopathology, but as clinician rated relevance increases, associations get stronger and become evident across more domains.

Obsessive-compulsive symptoms in children with first degree relatives diagnosed with obsessive-compulsive disorder

Objective: A first-degree relative affected by obsessive-compulsive disorder (OCD) and obsessive-compulsive symptoms (OCS) in childhood is an important risk factor for developing the disorder in adulthood. The relationship between a family history of OCD and the presence of OCS and its correlates in childhood is not well established. Methods: A total of 66 children whose parents or siblings have been diagnosed with OCD were assessed for the presence of OCS and clinical correlates. Results: Three children (4.5%) were reported to have received an OCD diagnosis and another 26 (39.4%) were identified as having OCS. Children with OCS had higher rates of coercive behavior and came from families with lower socioeconomic status. Contamination/cleaning dimension symptoms in the proband were associated with OCS in the assessed children. Conclusion: OCS are frequent among family members of individuals with OCD and are associated with socioeconomic status, coercive behaviors and proband contamination/cleaning symptoms. Future longitudinal studies should test the risk of developing OCD in association with these characteristics.

Obsessive-compulsive symptoms in children with first degree relatives diagnosed with obsessive-compulsive disorder.

OBJECTIVE: A first-degree relative affected by obsessive-compulsive disorder (OCD) and obsessive-compulsive symptoms (OCS) in childhood is an important risk factor for developing the disorder in adulthood. The relationship between a family history of OCD and the presence of OCS and its correlates in childhood is not well established. METHODS: A total of 66 children whose parents or siblings have been diagnosed with OCD were assessed for the presence of OCS and clinical correlates. RESULTS: Three children (4.5%) were reported to have received an OCD diagnosis and another 26 (39.4%) were identified as having OCS. Children with OCS had higher rates of coercive behavior and came from families with lower socioeconomic status. Contamination/cleaning dimension symptoms in the proband were associated with OCS in the assessed children. CONCLUSION: OCS are frequent among family members of individuals with OCD and are associated with socioeconomic status, coercive behaviors and proband contamination/cleaning symptoms. Future longitudinal studies should test the risk of developing OCD in association with these characteristics.

The association between psychotic experiences and traumatic life events: the role of the intention to harm.

BACKGROUND: Previous work showed traumatic life events (TLE) with intention to harm, like bullying and abuse, to be more strongly associated with psychotic experiences (PE) than other types of trauma, like accidents. However, this association is subject to reporting bias and can be confounded by demographic characteristics and by differences in dose of exposure across different trauma categories. We studied the association between TLE with and without intention to harm and PE, taking into account potential confounders and biases. METHODS: A total of 2245 children and adolescents aged 6-14 years were interviewed by psychologists. The interview included the presence of 20 PE (both self-report and psychologist evaluation). In addition, parents provided information on child exposure to trauma, mental health and PE. RESULTS: Results showed no significant association between TLE without intention to harm only and PE for the three methods of assessment of PE (self-report, parent report and psychologist rating). On the other hand, there was a positive association between PE and TLE in groups exposed to traumatic experiences with intention to harm (with intention to harm only and with and without intention to harm). Results remained significant after controlling for demographic and clinical confounders, but this positive association was no longer significant after adjusting for the number of TLE. CONCLUSIONS: TLE with intention to harm display a stronger association with PE than TLE without intention to harm, and this difference is likely reducible to a greater level of traumatic exposure associated with TLE with intention to harm.

Diagnosing social anxiety in Parkinson's disease: characteristics and frequencies according to two diagnostic criteria

Abstract Background: Studies found inconsistent frequencies of social anxiety disorder (SAD) in Parkinson's disease (PD) (9.7%-50%). Previous reports did not test the impact of applying DSM-IV restrictive criteria that recommends the exclusion of secondary cases when diagnosing SAD in PD. Objective: Our aim is to estimate the frequency of social anxiety according to DSM-IV criteria and according to an inclusive broader approach. Methods: One hundred and ten PD patients were assessed for the presence of SAD using SCID-I, diagnosis of social anxiety were determined according to two different criteria: following and not following DSM-IV recommendation for exclusion of cases though to be secondary to a general medical condition. Results: SAD was present in 34 (31%) of patients, but 17 (15.5%) were secondary to a general medical condition. Patients with SAD were significantly younger, had earlier disease onset, had more severe PD symptoms, and were more frequently depressed. There was no difference in demographic and clinical features between primary and secondary SAD. Discussion: We conclude that the use of different diagnostic criteria may have a massive impact in the estimation of frequency of SAD in PD.

Children with Poor Reading Skills at the Word Level Show Reduced Fractional Anisotropy in White Matter Tracts of Both Hemispheres.

Diffusion tensor imaging (DTI) studies showed that microstructural alterations are correlated to reading skills. In this study, we aim to investigate white matter microstructure of a group of Portuguese speakers with poor reading level, using different parameters of DTI. To perform this analysis, we selected children ranging from 8 to 12 years of age, poor readers (n = 17) and good readers (n = 23), evaluated in the word-level ability based on a Latent Class Analysis (LCA) of Academic Performance Test (TDE). Poor readers exhibited significant fractional anisotropy (FA) reductions in many tracts of both hemispheres, but small and restricted clusters of increased radial diffusivity (RD) in the left hemisphere. Spatial coherence of fibers might be the main source of differences, as changes in FA were not similarly accompanied in terms of extension by changes in RD. Widespread structural alterations in the white matter could prevent good reading ability at word level, which is consistent with recent studies demonstrating the involvement of multiple cortical regions and white matter tracts in reading disabilities.

An integrative approach to investigate the respective roles of single-nucleotide variants and copy-number variants in Attention-Deficit/Hyperactivity Disorder.

Many studies have attempted to investigate the genetic susceptibility of Attention-Deficit/Hyperactivity Disorder (ADHD), but without much success. The present study aimed to analyze both single-nucleotide and copy-number variants contributing to the genetic architecture of ADHD. We generated exome data from 30 Brazilian trios with sporadic ADHD. We also analyzed a Brazilian sample of 503 children/adolescent controls from a High Risk Cohort Study for the Development of Childhood Psychiatric Disorders, and also previously published results of five CNV studies and one GWAS meta-analysis of ADHD involving children/adolescents. The results from the Brazilian trios showed that cases with de novo SNVs tend not to have de novo CNVs and vice-versa. Although the sample size is small, we could also see that various comorbidities are more frequent in cases with only inherited variants. Moreover, using only genes expressed in brain, we constructed two "in silico" protein-protein interaction networks, one with genes from any analysis, and other with genes with hits in two analyses. Topological and functional analyses of genes in this network uncovered genes related to synapse, cell adhesion, glutamatergic and serotoninergic pathways, both confirming findings of previous studies and capturing new genes and genetic variants in these pathways.

Obsessive-compulsive symptoms are associated with psychiatric comorbidities, behavioral and clinical problems: a population-based study of Brazilian school children.

Pediatric-onset obsessive-compulsive disorder (OCD) is underdiagnosed, and many affected children are untreated. The present study seeks to evaluate the presence and the clinical impact of OCD and obsessive-compulsive symptoms (OCS) in a large sample of school-age children. In Phase I, we performed an initial screening using the Family History Screen (FHS). In Phase II, we identified an "at-risk" sample, as well as a randomly selected group of children. A total of 2,512 children (6-12 years old) were assessed using the FHS, the Development and Well-Being Assessment (DAWBA), the Strengths and Difficulties Questionnaire (SDQ), and the Child Behavior Checklist (CBCL). Data analyses included descriptive and multivariate analytical techniques. 2,512 children (mean age: 8.86 ± 1.84 years; 55.0% male) were categorized into one of the three diagnostic groups: OCD (n = 77), OCS (n = 488), and unaffected controls (n = 1,947). There were no significant socio-demographic differences (age, gender, socioeconomic status) across groups. The OCS group resembled the OCD on overall impairment, including school problems and delinquent behaviors. However, the OCD group did have significantly higher rates of several comorbid psychiatric disorders, including separation anxiety, generalized anxiety, and major depressive disorder, than OCS or unaffected controls. Moreover, the OCD group also scored higher than the SDQ, as well as on each of CBCL items rated by the parent. Our findings suggest that there is a psychopathological continuum between OCS and OCD in school-aged children. The presence of OCS is associated with functional impairment, which needs further investigation in longitudinal studies.

Obsessive-compulsive symptom dimensions in a population-based, cross-sectional sample of school-aged children.

BACKGROUND: Obsessive-compulsive disorder can be expressed as four potentially overlapping obsessive-compulsive symptom (OCS) dimensions (OCSD) ("symmetry/ordering", "contamination/cleaning", "aggressive/sexual/religious" and "collecting/hoarding"). In clinical samples, some dimensions are more familial and associated with increased psychiatric comorbidity and malfunctioning. However, data concerning OCS and OCSD are scarce in non-clinical samples, particularly among children. The present study aims to estimate: (1) the prevalence and sex/age distribution of OCS/OCSD in a community-based sample of schoolchildren; (2) the association between OCS and additional clinical factors; and (3) the degree of familial aggregation of OCS/OCSD. METHODS: OCS and OCSD were evaluated in 9937 Brazilian school-children (6-12 years-old) and their biological relatives using the Family History Screen. Data analyses included gradient estimated equations and post-hoc tests. RESULTS: We included data on 9937 index-children, 3305 siblings (13-18 years-old), and 16,218 parents. Biological mothers were the informants in 87.6% of the interviews. OCS were present in 14.7% of the index-children; 15.6% of their siblings; 34.6% of their mothers and 12.1% of their fathers. The prevalence of OCS and each of the OCSD gradually increased from ages 6 to 12 years. Overall, OCS in children were associated with the presence of other psychiatric symptoms, as well as behavioral/school impairment. OCS and each of the four OCSD aggregated significantly within families. CONCLUSIONS: OCS are prevalent and associated with psychiatric symptoms and clinical impairment among school-aged children. OCSD aggregate within families in a dimension-specific fashion. These findings suggest a natural continuum between OCS and OCD with regard to their dimensional character.

High risk cohort study for psychiatric disorders in childhood: rationale, design, methods and preliminary results.

The objective of this study is to present the rationale, methods, design and preliminary results from the High Risk Cohort Study for the Development of Childhood Psychiatric Disorders. We describe the sample selection and the components of each phases of the study, its instruments, tasks and procedures. Preliminary results are limited to the baseline phase and encompass: (i) the efficacy of the oversampling procedure used to increase the frequency of both child and family psychopathology; (ii) interrater reliability and (iii) the role of differential participation rate. A total of 9937 children from 57 schools participated in the screening procedures. From those 2512 (random = 958; high risk = 1554) were further evaluated with diagnostic instruments. The prevalence of any child mental disorder in the random strata and high-risk strata was 19.9% and 29.7%. The oversampling procedure was successful in selecting a sample with higher family rates of any mental disorders according to diagnostic instruments. Interrater reliability (kappa) for the main diagnostic instrument range from 0.72 (hyperkinetic disorders) to 0.84 (emotional disorders). The screening instrument was successful in selecting a sub-sample with "high risk" for developing mental disorders. This study may help advance the field of child psychiatry and ultimately provide useful clinical information.

Depression increases in patients with Parkinson?s disease according to the increasing severity of the cognitive impairment.

OBJECTIVE: To test the hypothesis that severity of cognitive impairment modifies the association between depression and Parkinson's disease (PD). METHOD: One-phase population-based door-to-door surveys. This is a secondary analysis of 1,451 people aged 65 years and older with cognitive impairment living in defined catchment areas. Depression was estimated according to ICD-10, self-reported PD, disability according to WHODAS-II and cognitive status according to the CSI-D. RESULTS: The mean age of the sample was 79.3 years old and most (69%) were women. Of the total sample, 16.1% had depression and it was significantly higher among participants with PD. There was an increase on the ORs of the association between depression and PD with decreased scores in the cognitive test (Adjusted OR from 0.98 to 8.04). CONCLUSION: The association between depression and PD increases with the severity of the cognitive impairment.

Depression increases in patients with Parkinson?s disease according to the increasing severity of the cognitive impairment / Em pacientes com doença de Parkinson, a depressão aumenta de acordo com o aumento da gravidade do comprometimento cognitivo

Objective : To test the hypothesis that severity of cognitive impairment modifies the association between depression and Parkinson’s disease (PD). Method : One-phase population-based door-to-door surveys. This is a secondary analysis of 1,451 people aged 65 years and older with cognitive impairment living in defined catchment areas. Depression was estimated according to ICD-10, self-reported PD, disability according to WHODAS-II and cognitive status according to the CSI-D. Results : The mean age of the sample was 79.3 years old and most (69%) were women. Of the total sample, 16.1% had depression and it was significantly higher among participants with PD. There was an increase on the ORs of the association between depression and PD with decreased scores in the cognitive test (Adjusted OR from 0.98 to 8.04). Conclusion : The association between depression and PD increases with the severity of the cognitive impairment. .

Objetivo : Testar a hipótese que a gravidade do prejuízo cognitivo modifica a associação entre depressão e doença de Parkinson (DP). Método : Estudo populacional através da análise secundária de 1.451 pessoas com idade maior ou igual a 65 anos com prejuízo cognitivo que residiam em áreas de abrangência definidas. A depressão foi estimada de acordo com a CID-10, auto-relato de DP, incapacidade conforme a WHODAS-II e nível cognitvo de acordo com a CSI-D. Resultado : A média de idade foi 79,3 anos, predominaram as mulheres (69%). Do total de indivíduos, 16,1% tinham depressão, significantemente maior entre os participantes com DP. Houve aumento gradativo na OR relativa à associação entre depressão e DP com a diminuição do escore no teste cognitivo (OR ajustado variou de 0,98 a 8,04). Conclusão : A associação entre depressão e DP parece aumentar com a gravidade do prejuízo cognitivo. .

Manic symptoms in youth: dimensions, latent classes, and associations with parental psychopathology.

OBJECTIVE: The purpose of the study was to define the latent structure of parent-reported manic symptoms and their association with functional impairment and familial risk in a community sample of Brazilian children. METHOD: We screened for manic symptoms in a community sample of 2,512 children 6 to 12 years of age. Parents of children with "episodes of going abnormally high" completed a detailed mania section (n = 479; 19.1%). Confirmatory factor analysis (CFA) tested a solution with "Under-Control (UC)" and "Exuberant (EX)" dimensions, investigating the severity (threshold) and factor loading of each symptom. We also used latent class analysis (LCA) to evaluate the latent categorical structure of manic symptoms. Associations of these latent constructs with psychiatric comorbidity, psychosocial impairment, and family history of psychopathology were tested. RESULTS: The 2-dimensional model fit the data well. Only the UC dimension was associated with psychiatric morbidity, psychosocial impairment, and a family history of mania, depression, or suicide attempts. Both UC and EX items discriminated subjects with "episodes of going abnormally high," but EX items lay at the mild end of the severity spectrum, whereas UC items lay at the severe end. The LCA yielded a small group of children with high levels of manic symptoms and a distinct profile of psychiatric comorbidity and impairment ("high-symptom group"). CONCLUSION: In a large, community-based sample, we found a 2-dimensional latent structure for parent-reported manic symptoms in youth, and demonstrated familial associations between the UC dimension and affective disorders. Both UC and EX items are clinically useful, but their contributions vary with symptom severity.