Psychopathology in never-treated schizophrenia

COSMIN systematic review and meta-analysis of the measurement properties of the Positive and Negative Syndrome Scale (PANSS)

Background

The Positive and Negative Syndrome Scale (PANSS) is the most widely used tool for assessing the symptoms of schizophrenia. Despite its widespread use, the psychometric properties of the PANSS have not been systematically reviewed. This study fills that gap in the scientific literature.

Methods

We utilized the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guideline for systematic reviews and meta-analytical procedures to assess the psychometric properties of the PANSS in its original three-subscale form as well as the quality level of the evidence available. On this basis we formulated recommendations for future research and use. A study protocol was registered under 10.17605/OSF.IO/5EGMD. The search period was until February 21, 2024.

Findings

We included 119 publications. According to COSMIN, the PANSS demonstrated sufficient reliability, construct validity, and responsiveness; but had significant shortcomings in content validity and structural validity. The original three-factor model showed poor structural validity, leading to its COSMIN classification as "not recommendable". The subscales showed overall acceptable measurement properties. However, the lack of structural validity of the three-subscale model renders its subscales less useful. Moreover, the PANSS negative subscale does not cover all domains of the National Institute of Mental Health consensus. Due to the length of the instrument (30-50 min), it is barely useable in clinical practice.

Interpretation

Although the PANSS is the standard scale for schizophrenia symptom severity, its shortcomings regarding fundamental psychometric domains and practical applicability warrant the development of new scales for which appropriate methods should be applied from the start.

Funding

There was no specific funding source for this research.

COSMIN review of the PANSS Marder factor solution and other factor models in people with schizophrenia

The Positive and Negative Syndrome Scale (PANSS) is widely used to assess schizophrenia symptoms. Initially designed with three subscales, Marder et al.´s 5-factor-Model (M5M) first proposed in 1997 has been frequently used in treatment trials, but it has never been systematically reviewed for its measurement properties. We utilized the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) guideline for systematic reviews and meta-analytical procedures to assess the psychometric properties of the M5M-PANSS. COSMIN comprises several steps: literature search, risk-of-bias assessments, assessing the updated criteria for good measurement properties, feasibility aspects and grading the quality of the evidence. We further assessed the goodness of fit of other PANSS factor models. We included 95 publications. The M5M-PANSS showed good construct validity, but "insufficient" structural validity. Evidence of other COSMIN domains is largely lacking. Among the multiple (73) factor solutions examined with confirmatory methods, several other 5-factor solutions had better model fit. According to COSMIN rules the M5M should not be recommended for use. Other five-factor models such as the one proposed by Wallwork et al.1 warrant further evaluation. Nevertheless, the factor composition of the M5M and these other models was relatively similar, so previously published results should not be disregarded.

Mismatch Negativity and P3a Impairment through Different Phases of Schizophrenia and Their Association with Real-Life Functioning

Impairment in functioning since the onset of psychosis and further deterioration over time is a key aspect of subjects with schizophrenia (SCZ). Mismatch negativity (MMN) and P3a, indices of early attention processing that are often impaired in schizophrenia, might represent optimal electrophysiological candidate biomarkers of illness progression and poor outcome. However, contrasting findings are reported about the relationships between MMN-P3a and functioning. The study aimed to investigate in SCZ the influence of illness duration on MMN-P3a and the relationship of MMN-P3a with functioning. Pitch (p) and duration (d) MMN-P3a were investigated in 117 SCZ and 61 healthy controls (HCs). SCZ were divided into four illness duration groups: ≤ 5, 6 to 13, 14 to 18, and 19 to 32 years. p-MMN and d-MMN amplitude was reduced in SCZ compared to HCs, independently from illness duration, psychopathology, and neurocognitive deficits. p-MMN reduction was associated with lower "Work skills". The p-P3a amplitude was reduced in the SCZ group with longest illness duration compared to HCs. No relationship between P3a and functioning was found. Our results suggested that MMN amplitude reduction might represent a biomarker of poor functioning in SCZ.

Meta-analysis of the positive and Negative Syndrome Scale (PANSS) factor structure

A meta-analysis of the results of 45 factor analyses (n = 22,812) of the Positive and Negative Syndrome Scale (PANSS) was conducted. Meta-analyses of the PANSS was conducted using both a co-occurrence similarity matrix and reproduced correlations. Both methods produced similar results. Five factors (Positive Symptoms, Negative Symptoms, Disorganization, Affect and Resistance) emerged clearly across both analyses. The factors and the items defining them were Positive Symptoms (P1 Delusions, G9 Unusual thought content, P3 Hallucinatory behavior, P6 Suspiciousness and persecution, P5 Grandiosity), Negative Symptoms (N2 Emotional withdrawal, N1 Blunted affect, N4 Passive apathetic social withdrawal, N6 Lack of spontaneity, N3 Poor rapport, G7 Motor retardation, G16 Active social avoidance), Disorganization often termed Cognitive (P2 Conceptual disorganization, G11 Poor attention, N5 Difficulty in abstract thinking, G13 Disturbance of volition, N7 Stereotyped thinking, G5 Mannerisms/posturing, G15 Preoccupation, G10 Disorientation), Affect often termed Depression-Anxiety (G2 Anxiety, G6 Depression, G3 Guilt feelings, G4 Tension, G1 Somatic concern) and a small fifth factor that might be characterized as Resistance or Excitement/Activity (P7 Hostility, G14 Poor impulse control, P4 Excitement, G8 Uncooperativeness). Items G1, G4, G10, P5, G5, G15 may not be core items for the PANSS factors and G12 lack of judgment is not a core item. Results of the PANSS meta-analyses were relatively similar to those for meta-analysis of both the BPRS and BPRS-E all of which contain the original 18 BPRS items. The PANSS is distinguished by a much larger number of items to clearly define and measure Negative Symptoms as well as a sufficient number of items to much more clearly identify a Disorganization factor than the BPRS or BPRS-E.

Different outcomes of never-treated and treated patients with schizophrenia: 14-year follow-up study in rural China

BACKGROUND

The long-term outcome of never-treated patients with schizophrenia is unclear.

AIMS

To compare the 14-year outcomes of never-treated and treated patients with schizophrenia and to establish predictors for never being treated.

METHOD

All participants with schizophrenia (n = 510) in Xinjin, Chengdu, China were identified in an epidemiological investigation of 123 572 people and followed up from 1994 to 2008.

RESULTS

The results showed that there were 30.6%, 25.0% and 20.4% of patients who received no antipsychotic medication in 1994, 2004 and 2008 respectively. Compared with treated patients, those who were never treated in 2008 were significantly older, had significantly fewer family members, had higher rates of homelessness, death from other causes, being unmarried, living alone, being without a caregiver and poor family attitudes. Partial and complete remission in treated patients (57.3%) was significantly higher than that in the never-treated group (29.8%). Predictors of being in the never-treated group in 2008 encompassed baseline never-treated status, being without a caregiver and poor mental health status in 1994.

CONCLUSIONS

Many patients with schizophrenia still do not receive antipsychotic medication in rural areas of China. The 14-year follow-up showed that outcomes for the untreated group were worse. Community-based mental healthcare, health insurance and family intervention are crucial for earlier diagnosis, treatment and rehabilitation in the community.

Cognition and the five-factor model of the positive and negative syndrome scale in schizophrenia

Different exploratory and confirmatory factorial analyses of the Positive and Negative Syndrome Scale (PANSS) have found a number of factors other than the original positive, negative, and general psychopathology. Based on a review of previous studies and using confirmatory factor analyses (CFA), Wallwork et al. (Schizophr Res 2012; 137: 246-250) have recently proposed a consensus five-factor structure of the PANSS. This solution includes a cognitive factor which could be a useful measure of cognition in schizophrenia. Our objectives were 1) to study the psychometric properties (factorial structure and reliability) of this consensus five-factor model of the PANSS, and 2) to study the relationship between executive performance assessed using the Wisconsin Card Sorting Test (WCST) and the proposed PANSS consensus cognitive factor (composed by items P2-N5-G11). This cross-sectional study included a final sample of 201 Spanish outpatients diagnosed with schizophrenia. For our first objective, CFA was performed and Cronbach's alphas of the five factors were calculated; for the second objective, sequential linear regression analyses were used. The results of the CFA showed acceptable fit indices (NNFI=0.94, CFI=0.95, RMSEA=0.08). Cronbach's alphas of the five factors were adequate. Regression analyses showed that this five-factor model of the PANSS explained more of the WCST variance than the classical three-factor model. Moreover, higher cognitive factor scores were associated with worse WCST performance. These results supporting its factorial structure and reliability provide robustness to this consensus PANSS five-factor model, and indicate some usefulness of the cognitive factor in the clinical assessment of schizophrenic patients.

Effects of duration of untreated psychosis on long-term outcome of people hospitalized with first episode schizophrenia

Duration of untreated psychosis (DUP) has emerged as a reliable predictor of outcome but continues to remain under scientific scrutiny. The present study examines the effect of differential periods of DUP on long-term outcome of first episode schizophrenia at Mumbai, India. This research was a prospective, 10-year follow-up naturalistic study. Hospitalized patients of first episode schizophrenia were selected and followed up. Results showed that the mean DUP was higher for a group which showed clinical recovery on Clinical Global Impression Scale [14.0 months (SD=8.0) in recovered and 10.8 months (SD=5.7) in non-recovered group (P=0.091)]. DUP was not found to be significantly associated with any of the end point parameters of good clinical or social outcome. Thus, this study found that DUP alone does not determine outcome status confirming the role of psychopathological heterogeneity.

Differences in mortality and suicidal behaviour between treated and never-treated people with schizophrenia in rural China

BACKGROUND

Many people with schizophrenia remain untreated in the community. Long-term mortality and suicidal behaviour among never-treated individuals with schizophrenia in the community are unknown.

AIMS

To explore 10-year mortality and suicidal behaviour among never-treated individuals with schizophrenia.

METHOD

We used data from a 10-year prospective follow-up study (1994-2004) among people with schizophrenia in Xinjin County, Chengdu, China.

RESULTS

The mortality rate for never-treated individuals with schizophrenia was 2761 per 100 000 person-years during follow-up. There were no significant differences of rates of suicide and all-cause mortality between never-treated and treated individuals. The standardised mortality ratio (SMR) for never-treated people was 10.4 (95% CI 7.2-15.2) and for treated individuals 6.5 (95% CI 5.2-8.5). Compared with treated people, never-treated individuals were more likely to be older, poorer, have a longer duration of illness, marked symptoms and fewer family members.

CONCLUSIONS

The never-treated individuals have similar mortality to and a higher proportion of marked symptoms than treated people, which may reflect the poor outcome of the individuals without treatment. The higher rates of mortality, homelessness and never being treated among people with schizophrenia in low- and middle-income nations might challenge presumed wisdom about schizophrenia outcomes in these countries.

Schizophrenia, "just the facts" 4. Clinical features and conceptualization

Although dementia praecox or schizophrenia has been considered a unique disease entity for the past century, its definitions and boundaries have continued to vary over this period. At any given time, the changing concept of schizophrenia has been influenced by available diagnostic tools and treatments, related conditions from which it most needs to be distinguished, extant knowledge and scientific paradigms. There is significant heterogeneity in the etiopathology, symptomatology, and course of schizophrenia. It is characterized by an admixture of positive, negative, cognitive, mood, and motor symptoms whose severity varies across patients and through the course of the illness. Positive symptoms usually first begin in adolescence or early adulthood, but are often preceded by varying degrees of negative and cognitive symptomatology. Schizophrenia tends to be a chronic and relapsing disorder with generally incomplete remissions, variable degrees of functional impairment and social disability, frequent comorbid substance abuse, and decreased longevity. Although schizophrenia may not represent a single disease with a unitary etiology or pathogenetic process, alternative approaches have thus far been unsuccessful in better defining this syndrome or its component entities. The symptomatologic, course, and etio-pathological heterogeneity can usefully be addressed by a dimensional approach to psychopathology, a clinical staging approach to illness course, and by elucidating endophenotypes and markers of illness progression, respectively. This will allow an approach to the deconstruction of schizophrenia into its multiple component parts and strategies to reconfigure these components in a more meaningful manner. Possible implications for DSM-V and ICD-11 definitions of schizophrenia are discussed.