Common Taxonomy of Traits and Symptoms: Linking Schizophrenia Symptoms, Schizotypy, and Normal Personality

Abstract The associations among normal personality and many mental disorders are well established, but it remains unclear whether and how symptoms of schizophrenia and schizotypal traits align with the personality taxonomy. This study examined the joint factor structure of normal personality, schizotypy, and schizophrenia symptoms in people with psychotic disorders (n = 288) and never-psychotic adults (n = 257) in the Suffolk County Mental Health Project. First, we evaluated the structure of schizotypal (positive schizotypy, negative schizotypy, and mistrust) and normal traits. In both the psychotic-disorder and never-psychotic groups, the best-fitting model had 5 factors: neuroticism, extraversion, conscientiousness, agreeableness, and psychoticism. The schizotypy traits were placed on different dimensions: negative schizotypy went on (low) extraversion, whereas positive schizotypy and mistrust went on psychoticism. Next, we added symptoms to the model. Numerous alternatives were compared, and the 5-factor model remained best-fitting. Reality distortion (hallucinations and delusions) and disorganization symptoms were placed on psychoticism, and negative symptoms were placed on extraversion. Models that separated symptom dimensions from trait dimensions did not fit well, arguing that taxonomies of symptoms and traits are aligned. This is the first study to show that symptoms of psychosis, schizotypy, and normal personality reflect the same underlying dimensions. Specifically, (low) extraversion, negative schizotypy, and negative symptoms form one spectrum, whereas psychoticism, positive schizotypy, and positive and disorganized symptoms form another. This framework helps to understand the heterogeneity of psychosis and comorbidity patterns found in psychotic disorders. It also underscores the importance of traits to understanding these disorders.

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The effect of the environment on symptom dimensions in the first episode of psychosis: a multilevel study

Psychological Medicine ◽

10.1017/s0033291713003188 ◽

2014 ◽

Vol 44 (11) ◽

pp. 2419-2430 ◽

Cited By ~ 17

Author(s):

F. J. Oher ◽

A. Demjaha ◽

D. Jackson ◽

C. Morgan ◽

P. Dazzan ◽

...

Keyword(s):

Depressive Symptoms ◽

Population Density ◽

Negative Symptoms ◽

Psychotic Disorders ◽

Urban Environments ◽

Psychotic Symptoms ◽

First Episode ◽

Multilevel Regression ◽

Symptom Dimensions ◽

Reality Distortion

BackgroundThe extent to which different symptom dimensions vary according to epidemiological factors associated with categorical definitions of first-episode psychosis (FEP) is unknown. We hypothesized that positive psychotic symptoms, including paranoid delusions and depressive symptoms, would be more prominent in more urban environments.MethodWe collected clinical and epidemiological data on 469 people with FEP (ICD-10 F10–F33) in two centres of the Aetiology and Ethnicity in Schizophrenia and Other Psychoses (AESOP) study: Southeast London and Nottinghamshire. We used multilevel regression models to examine neighbourhood-level and between-centre differences in five symptom dimensions (reality distortion, negative symptoms, manic symptoms, depressive symptoms and disorganization) underpinning Schedules for Clinical Assessment in Neuropsychiatry (SCAN) Item Group Checklist (IGC) symptoms. Delusions of persecution and reference, along with other individual IGC symptoms, were inspected for area-level variation.ResultsReality distortion [estimated effect size (EES) 0.15, 95% confidence interval (CI) 0.06–0.24] and depressive symptoms (EES 0.21, 95% CI 0.07–0.34) were elevated in people with FEP living in more urban Southeast London but disorganized symptomatology was lower (EES –0.06, 95% CI –0.10 to –0.02), after controlling for confounders. Delusions of persecution were not associated with increased neighbourhood population density [adjusted odds ratio (aOR) 1.01, 95% CI 0.83–1.23], although an effect was observed for delusions of reference (aOR 1.41, 95% CI 1.12–1.77). Hallucinatory symptoms showed consistent elevation in more densely populated neighbourhoods (aOR 1.32, 95% CI 1.09–1.61).ConclusionsIn people experiencing FEP, elevated levels of reality distortion and depressive symptoms were observed in more urban, densely populated neighbourhoods. No clear association was observed for paranoid delusions; hallucinations were consistently associated with increased population density. These results suggest that urban environments may affect the syndromal presentation of psychotic disorders.

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Schizophrenia polygenic risk score and 20-year course of illness in psychotic disorders

Translational Psychiatry ◽

10.1038/s41398-019-0612-5 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 11

Author(s):

Katherine G. Jonas ◽

Todd Lencz ◽

Kaiqiao Li ◽

Anil K. Malhotra ◽

Greg Perlman ◽

...

Keyword(s):

Risk Score ◽

Negative Symptoms ◽

Psychotic Disorders ◽

Illness Severity ◽

Polygenic Risk Score ◽

Course Of Illness ◽

Polygenic Risk ◽

County Mental Health ◽

Health Project ◽

First Admission

AbstractUnderstanding whether and how the schizophrenia polygenic risk score (SZ PRS) predicts course of illness could improve diagnosis and prognostication in psychotic disorders. We tested whether the SZ PRS predicts symptoms, cognition, illness severity, and diagnostic changes over the 20 years following first admission. The Suffolk County Mental Health Project is an inception cohort study of first-admission patients with psychosis. Patients were assessed six times over 20 years, and 249 provided DNA. Geographically- and demographically-matched never psychotic adults were recruited at year 20, and 205 provided DNA. Symptoms were rated using the Schedule for the Assessment of Positive Symptoms and Schedule for the Assessment of Negative Symptoms. Cognition was evaluated with a comprehensive neuropsychological battery. Illness severity and diagnosis were determined by consensus of study psychiatrists. SZ PRS was significantly higher in first-admission than never psychotic groups. Within the psychosis cohort, the SZ PRS predicted more severe negative symptoms (β = 0.21), greater illness severity (β = 0.28), and worse cognition (β = −0.35), across the follow-up. The SZ PRS was the strongest predictor of diagnostic shifts from affective to non-affective psychosis over the 20 years (AUC = 0.62). The SZ PRS predicts persistent differences in cognition and negative symptoms. The SZ PRS also predicts who among those who appear to have a mood disorder with psychosis at first admission will ultimately be diagnosed with a schizophrenia spectrum disorder. These findings show potential for the SZ PRS to become a tool for diagnosis and treatment planning.

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Schizophrenia Polygenic Risk Score and 20-Year Course of Illness in Psychotic Disorders

10.1101/581579 ◽

2019 ◽

Author(s):

Katherine G. Jonas ◽

Todd Lencz ◽

Kaiqiao Li ◽

Anil K. Malhotra ◽

Greg Perlman ◽

...

Keyword(s):

Risk Score ◽

Negative Symptoms ◽

Psychotic Disorders ◽

Illness Severity ◽

Polygenic Risk Score ◽

Course Of Illness ◽

Polygenic Risk ◽

County Mental Health ◽

Health Project ◽

First Admission

AbstractUnderstanding whether and how the schizophrenia polygenic risk score (SZ PRS) predicts course of illness could improve diagnostics and prognostication in psychotic disorders. We tested whether the SZ PRS predicts symptoms, cognition, illness severity, and diagnostic changes over the 20 years following first admission. The Suffolk County Mental Health Project is an inception cohort study of first-admission patients with psychosis. Patients were assessed six times over 20 years, and 249 provided DNA. Geographically- and demographically-matched never psychotic adults were recruited at year 20, and 205 provided DNA. Symptoms were rated using the Schedule for the Assessment of Positive Symptoms and Schedule for the Assessment of Negative Symptoms. Cognition was evaluated with a comprehensive neuropsychological battery. Illness severity and diagnosis were determined by consensus of study psychiatrists. SZ PRS was significantly higher in first-admission than never psychotic groups. Within the psychosis cohort, the SZ PRS predicted more severe negative symptoms (β= 0.21), lower GAF (β= −0.28), and worse cognition (β= −0.35), across the follow-up. The SZ PRS was the strongest predictor of diagnostic shifts from affective to non-affective psychosis over the 20 years (AUC = 0.62). The SZ PRS predicts persistent differences in cognition and negative symptoms. The SZ PRS also predicts who among those who appear to have a mood disorder with psychosis at first admission will ultimately be diagnosed with a schizophrenia spectrum disorder. These findings show potential for the SZ PRS to become a powerful tool for diagnosis and treatment planning.

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Factor Analysis of Negative Symptom Items in the Structured Interview for Prodromal Syndromes

Schizophrenia Bulletin ◽

10.1093/schbul/sby177 ◽

2018 ◽

Vol 45 (5) ◽

pp. 1042-1050 ◽

Cited By ~ 9

Author(s):

Matilda Azis ◽

Gregory P Strauss ◽

Elaine Walker ◽

William Revelle ◽

Richard Zinbarg ◽

...

Keyword(s):

Factor Analysis ◽

Functional Outcome ◽

Negative Symptom ◽

Negative Symptoms ◽

Psychotic Disorders ◽

The United States ◽

Structured Interview ◽

Symptom Dimensions ◽

Increased Risk ◽

Active Research

Abstract Background Negative symptoms occur early in the clinical high risk (CHR) state and indicate increased risk of conversion to psychotic disorder and poor functional outcome. However, while the negative symptom domain has shown to be parsimoniously explained by a 2-factor construct in schizophrenia, there has yet to be an established factor structure of negative symptoms in CHR. Methods 214 individuals meeting the Structured Interview for Psychosis-Risk Syndromes (SIPS) criteria for CHR were recruited through 3 active research programs in the United States. Exploratory Factor Analysis was conducted on the 6 negative symptom items of the SIPS, and factors were evaluated with respect to functional outcome and depression. Results Factor analysis indicated a 2-factor hierarchical model with 2 negative symptom dimensions reflecting volition (Occupational Functioning and Avolition) and emotion (Expression of Emotion, Experience of Emotion and Social Anhedonia). Linear Regression showed that the emotion factor was associated with poor social function, and the volition factor was associated with poor role function and depression. Conclusions Similar to factor solutions identified in adults diagnosed with psychotic disorders, results indicated that the SIPS negative symptom subscale is not a unidimensional construct. Rather, the SIPS negative subscale has 2 distinct factors that have different associations with clinical outcome and should be interpreted independently. Results have significant relevance for informing the valid assessment and conceptual interpretation of early clinical phenomenology in the psychosis prodrome.

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BDNF and S100B in psychotic disorders: evidence for an association with treatment responsiveness

Acta Neuropsychiatrica ◽

10.1017/neu.2013.59 ◽

2013 ◽

Vol 26 (4) ◽

pp. 223-229 ◽

Cited By ~ 3

Author(s):

Noortje W.A. van de Kerkhof ◽

Durk Fekkes ◽

Frank M.M.A. van der Heijden ◽

Willem M.A. Verhoeven

Keyword(s):

Negative Symptoms ◽

Psychotic Disorders ◽

Brain Plasticity ◽

Control Sample ◽

Serum Levels ◽

Response To Treatment ◽

Antipsychotic Treatment ◽

Specific Symptom ◽

Symptom Dimensions ◽

Symptom Profile

ObjectiveBrain-derived neurotrophic factor (BDNF) and S100B are involved in brain plasticity processes and their serum levels have been demonstrated to be altered in patients with psychoses. This study aimed to identify subgroups of patients with psychotic disorders across diagnostic boundaries that show a specific symptom profile or response to treatment with antipsychotics, by measuring serum levels of BDNF and S100B.MethodsThe study sample consisted of 58 patients with DSM-IV psychotic disorders. Comprehensive Assessment of Symptoms and History (CASH), Positive and Negative Syndrome Scale (PANSS) and Clinical Global Impression scale for severity and improvement (CGI-S/CGI-I) were applied at baseline and after 6 weeks of antipsychotic treatment. At both time points, serum levels of BDNF and S100B were measured and compared with a matched control sample.ResultsBaseline BDNF and S100B levels were significantly lower in patients as compared with controls and did not change significantly during treatment. Dividing the patient sample according to baseline biochemical parameters (low and high 25% and middle 50%), no differences in symptom profiles or outcome were found with respect to BDNF. However, the subgroups with low and high S100B levels had higher PANSS scores than the middle subgroup. In addition, the high subgroup still showed significantly more negative symptoms after treatment, whereas the low subgroup showed more positive symptoms compared with the other subgroups.ConclusionSerum levels of BDNF and S100B are lowered in patients with psychotic disorders across diagnostic boundaries. The differences between high and low S100B subgroups suggest a relationship between S100B, symptom dimensions and treatment response, irrespective of diagnostic categories.

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The Suffolk County Mental Health Project: demographic, pre-morbid and clinical correlates of 6-month outcome

Psychological Medicine ◽

10.1017/s0033291700035285 ◽

1996 ◽

Vol 26 (5) ◽

pp. 953-962 ◽

Cited By ~ 33

Author(s):

E. J. Bromet ◽

L. Jandorf ◽

S. Fennig ◽

J. Lavelle ◽

B. Kovasznay ◽

...

Keyword(s):

Mental Health ◽

New York ◽

Negative Symptoms ◽

Suffolk County ◽

Prognostic Indicators ◽

Background Characteristics ◽

County Mental Health ◽

Health Project ◽

Initial Hospitalization

SynopsisThe diagnostic specificity and predictive utility of the classical prognostic indicators in schizophrenia were examined in psychotic patients enrolled in the Suffolk County Mental Health Project. First-admission psychotic patients with schizophrenia (N= 96), major depression (N= 42), and bipolar disorder (N= 64) drawn from 10 facilities in Suffolk County, New York, were assessed during their initial hospitalization and at 6–month follow-up. Longitudinal consensus diagnoses were determined after the 6-month interview. The diagnostic groups shared similar background characteristics, but schizophrenics had poorer pre-morbid adjustment, longer periods of psychosis before hospitalization and more negative symptoms initially. Except for rehospitalization, schizophrenics had the worst and bipolars the best functioning at follow-up. Among the classical prognostic indicators, the best predictor of 6-month outcome for each diagnostic group was premorbid functioning.

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Service Use and Outcomes of First-Admission Patients With Psychotic Disorders in the Suffolk County Mental Health Project

American Journal of Psychiatry ◽

10.1176/appi.ajp.162.7.1291 ◽

2005 ◽

Vol 162 (7) ◽

pp. 1291-1298 ◽

Cited By ~ 16

Author(s):

Ramin Mojtabai ◽

Daniel Herman ◽

Ezra S. Susser ◽

Nancy Sohler ◽

Thomas J. Craig ◽

...

Keyword(s):

Mental Health ◽

Service Use ◽

Psychotic Disorders ◽

Suffolk County ◽

County Mental Health ◽

Health Project ◽

First Admission

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Dynamic interplay between life events and course of psychotic disorders: 10-year longitudinal study following first admission

Psychological Medicine ◽

10.1017/s0033291720003992 ◽

2020 ◽

pp. 1-8

Author(s):

Kayla R. Donaldson ◽

Katherine G. Jonas ◽

Yuan Tian ◽

Emmett M. Larsen ◽

Daniel N. Klein ◽

...

Keyword(s):

Life Events ◽

Negative Symptoms ◽

Psychotic Disorders ◽

Negative Events ◽

First Onset ◽

Specific Symptoms ◽

The Impact ◽

The Relationship ◽

Reality Distortion ◽

First Admission

Abstract Background Life events (LEs) are a risk factor for first onset and relapse of psychotic disorders. However, the impact of LEs on specific symptoms – namely reality distortion, disorganization, negative symptoms, depression, and mania – remains unclear. Moreover, the differential effects of negative v. positive LEs are poorly understood. Methods The present study utilizes an epidemiologic cohort of patients (N = 428) ascertained at first-admission for psychosis and followed for a decade thereafter. Symptoms were assessed at 6-, 24-, 48-, and 120-month follow-ups. Results We examined symptom change within-person and found that negative events in the previous 6 months predicted an increase in reality distortion (β = 0.07), disorganized (β = 0.07), manic (β = 0.08), and depressive symptoms (β = 0.06), and a decrease in negative symptoms (β = −0.08). Conversely, positive LEs predicted fewer reality distortion (β = −0.04), disorganized (β = −0.04), and negative (β = −0.13) symptoms, and were unrelated to mood symptoms. A between-person approach to the same hypotheses confirmed that negative LEs predicted change in all symptoms, while positive LEs predicted change only in negative symptoms. In contrast, symptoms rarely predicted future LEs. Conclusions These findings confirm that LEs have an effect on symptoms, and thus contribute to the burden of psychotic disorders. That LEs increase positive symptoms and decrease negative symptoms suggest at least two different mechanisms underlying the relationship between LEs and symptoms. Our findings underscore the need for increased symptom monitoring following negative LEs, as symptoms may worsen during that time.

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