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Biomedical subjects

V Peralta

Publications and source records attributed to V Peralta.

At least 55 records · Page 3Linked to original sources
PubMed1995

Psychopathological dimensions in schizophrenia.

To test underlying latent syndromes within schizophrenic syndromes assessed by the Positive and Negative Syndrome Scale (PANSS), a sample of 100 DSM-III-R schizophrenia patients was obtained through a semistructured interview for schizophrenia. Confirmatory factor analysis was used to evaluate the underlying symptomatological dimensions. The positive and negative construct was not confirmed by this study. The three- and four-dimension models obtained higher goodness of fit than the one- or two-dimension models. Models composed of three or four dimensions shared positive and negative syndromes, in addition to "disorder of relating" and/or "disorganization" dimensions. The disorder of relating dimension of PANSS was composed of emotional withdrawal and passive/apathetic social withdrawal. The disorganization dimension comprised two symptoms of PANSS (conceptual disorganization and poor attention) and an item not included in the PANSS: inappropriate affect. It is suggested that a schedule for the assessment of this item be added to the PANSS.

Adolescent↗
PubMed1995

Negative symptoms in schizophrenia: a confirmatory factor analysis of competing models.

OBJECTIVE: The aim of the study was to examine different models of the factor structure of negative symptoms in schizophrenia through the use of a confirmatory factor analysis procedure. METHOD: The cohort comprised 253 inpatients diagnosed with schizophrenia according to DSM-III-R criteria. Negative symptoms were evaluated with the Scale for the Assessment of Negative Symptoms (SANS). Seven alternative models of negative symptoms were compared by means of confirmatory factor analysis. RESULTS: The unidimensional model fit the data modestly. More complex multifactorial models fit the data better than simpler models. Both five-dimension models corresponding to the original SANS structure fit the data quite well; the model excluding inappropriate affect from the SANS was the best adjusted. CONCLUSIONS: Multidimensional models fit the data better than the unidimensional model. The data provide evidence for the factorial validity of the SANS and the characterization of the SANS subscales as true underlying dimensions of observable negative symptoms.

Adult↗
PubMed1995

Is poor insight in psychotic disorders associated with poor performance on the Wisconsin Card Sorting Test?

OBJECTIVE: The purpose of this study was to test whether poor insight in patients with psychotic disorders is correlated with their performance on the Wisconsin Card Sorting Test. METHOD: The subjects included 52 psychotic patients (35 of whom had schizophrenia) given diagnoses according to DSM-III-R criteria. Their scores on the Wisconsin Card Sorting Test (number of categories and perseverative responses) were compared with those on three items measuring poor insight: lack of feeling ill, lack of insight, and uncooperativeness. RESULTS: None of the six correlations between scores on the two measures of the neuropsychological test and the three items measuring insight was significant. CONCLUSIONS: In spite of its limitations, this study suggests that poor insight may not be associated with poor performance on the Wisconsin Card Sorting Test.

Adult↗
PubMed1994

An empirical analysis of latent structures underlying schizophrenic symptoms: a four-syndrome model.

Various models of schizophrenia have postulated two syndromes (i.e., positive and negative), although other exploratory factor analyses have suggested a disorganization syndrome. We conducted a confirmatory factor analysis (CFA) on Schedule for the Assessment of Positive Symptoms (SAPS) and Schedule for the Assessment of Negative Symptoms (SANS) items and subscales to assess the latent structure of symptoms reflecting underlying pathological processes. The sample included 253 DSM-IIIR schizophrenic inpatients. Fourteen different models with one, two, three, or four syndromes were compared using CFA for "goodness of fit." The three-syndrome models displayed better fitness than any of the one- or two-syndrome models. All of the three-syndrome models shared the positive and negative dimensions; the third dimension in these three-syndrome models was either the disorganization or Strauss' relational dimensions. In the reported data, a four-syndrome model, including positive, disorganization, negative, and relational dimensions, showed excellent fitness. Despite its limitations, this study suggests the need to explore the validity of a four-syndrome model. The positive-negative model fits poorly with the data.

Adolescent↗
PubMed1994

Psychometric properties of the positive and negative syndrome scale (PANSS) in schizophrenia.

We analyzed the psychometric properties of the Positive and Negative Syndrome Scale (PANSS) in a sample of 100 DSM-III-R schizophrenic patients. Our findings coincided with the results of Kay's group in the following points: (1) the PANSS scores were normally distributed; (2) the positive and negative scales showed good interrater reliability; (3) positive and negative syndromes are independent constructs; (4) the positive and negative scales held a high concurrent validity in relation to the Scale for the Assessment of Positive Symptoms and the Scale for the Assessment of Negative Symptoms; and (5) although positive and negative syndromes showed factorial validity, they were not sufficient to account for the whole of the schizophrenic symptoms. Unlike Kay's group, we found a modest internal consistency of the positive scale, indicating that it is composed of several independent components. The data suggest that the distinction between positive and negative symptoms is an oversimplification, and that schizophrenic symptoms can be better conceptualized as composed of, at least three dimensional syndromes: positive, disorganized, and negative.

Adolescent↗
PubMed1994

Schizophrenic syndromes associated with treatment response.

1. The influence of clinical syndromes (determined by factor analysis) on treatment response was explored in a sample of schizophrenics treated by clinician choice. Patients were obtained from 115 consecutive admissions to an acute inpatient unit and were diagnosed by DSM-III-R criteria. Patients were thoroughly assessed during the first five days of hospitalization using SANS-SAPS, TLC and SEB. Factor analyses of these scales were carried out to explore the existence of syndromes made up of groups of symptoms. All patients were treated with neuroleptics and 70% with biperiden (to exclude akinesia). The response to treatment was measured by the CGI efficacy index. 2. Inappropriate affect, asociality, negative formal thought disturbances and bizarre behavior syndromes showed significant correlation with poor response to treatment. Affective flattening did not display consistent significant correlations with the response to treatment. Visual hallucinations (an infrequent syndrome) and manic thought disorder (a non-specific syndrome) showed significant correlations with better response to neuroleptics. 3. In a stepwise multiple regression model to predict treatment response, asociality and inappropriate affect were the most important predictors. In a discriminant analysis dividing patients between responders and non-responders, the syndromes predicting poor response were more important that those predicting good response.

Adolescent↗
PubMed1994

Lack of insight in schizophrenia.

A neuropsychological etiology has been suggested for lack of insight in schizophrenia patients, mainly based on frontal, right parietal, right hemisphere, or diffuse cerebral dysfunctions. The aim of this study ws to investigate the neuropsychological pathogeny of lack of insight in schizophrenia patients. We examined a sample of 40 DSM-III-R schizophrenia inpatients admitted because of a recrudescence of symptoms. Schizophrenic symptoms were evaluated through the Scale for the Assessment of Positive Symptoms and the Scale for the Assessment of Negative Symptoms. Neurologic explorations included an assessment of frontal neurologic signs, abnormal involuntary movements, and soft neurologic signs. Lack of insight was assessed through three items from the Manual for the Assessment and Documentation of Psychopathology (AMDP). A global index from these three items (lack of feeling ill, lack of insight, and uncooperativeness) was obtained. A neuropsychological battery composed of tests involving many functional areas of the brain was used. No correlation between bad performance and lack of insight was found on any test. On the contrary, lack of insight was associated with better performance on immediate verbal, immediate visual, and delayed visual memory tasks. Moreover, the three components of lack of insight were extracted as an independent factor when they were included together with the positive and negative symptoms, neurologic abnormalities (frontal and soft neurologic signs, and abnormal movements), and a global measure of cognitive performance. The results of the study do not support the neuropsychological hypothesis of lack of insight.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1994

Neuroleptic dose and schizophrenic symptoms. A survey of prescribing practices.

A study was conducted to survey the prescribing practices of neuroleptic doses in 100 consecutively hospitalized DSM-III-R schizophrenic patients. The relationship between doses and clinical and symptomatological variables was subsequently analyzed. Patients were evaluated through the Positive and Negative Syndrome Scale (PANSS). The peak mean dose in chlorpromazine equivalents was 1290 (range 250-7200). Haloperidol was the most commonly employed neuroleptic (67 patients). Neuroleptic doses were correlated with excitement, suspiciousness, hostility, uncooperativeness and poor impulse control. The neuroleptic doses administered in our hospital were similar to those found in other survey reports but higher than those recommended by the controlled dose-response studies. The correlation found between neuroleptic doses and symptoms of disruptive behavior suggests that we employed high-dose practices to treat the disruptive symptoms of schizophrenia. We concluded that it is useful to distinguish between the neuroleptic doses required to control the psychotic episode and those to treat the disruptive behavior.

Acute Disease↗
PubMed1993

Does formal thought disorder differ among patients with schizophrenic, schizophreniform and manic schizoaffective disorders?

The aim of this study was to examine whether specific forms of formal thought disorder distinguish schizophrenia from schizophreniform and schizoaffective psychoses. The sample was composed of 82 consecutively admitted patients with schizophrenic symptoms. Of these, 28 had a diagnosis of schizophrenia by RDC and DSM-IIIR criteria, 28 a diagnosis of schizophrenia by RDC but not DSM-IIIR (consequently they were labeled schizophreniform), and 26 a diagnosis of manic schizoaffective disorder by RDC criteria. They were assessed by a semi-structured interview for schizophrenia, by scales for positive and negative symptoms (SAPS and SANS) and by prognostic indicators. The assessment of thought disorder was carried out by using the Thought, Language and Communication scale (TLC). The schizophrenic patients showed higher global scores on formal thought disorder, and some of its subtypes were 'most specific' to schizophrenia (poverty of speech, poverty of content of speech, illogicality, tangentiality and perseveration). Schizophrenics had more loose associations than schizophreniforms. Manic schizoaffectives had higher scores on positive versus negative formal thought disorder than schizophreniforms. We suggested that the assessment of disordered thinking by the TLC may facilitate the differential diagnosis of psychotic disorders during the acute phase of the illness.

Adolescent↗
PubMed1993

Delusions and hallucinations in schizophrenic patients.

The Scale for Assessment of Positive Symptoms was used to measure delusions and hallucinations in 115 DSM-III-R schizophrenics. Our factorial analysis of the hallucinations and delusions resulted in three factors with appropriate internal consistency and frequency: a Schneiderian delusional syndrome, an auditory hallucination syndrome, and a paranoid syndrome that tend to be present in schizophrenics with later onset. These results should be cautiously interpreted due to their cross-sectional nature and to the size of the sample which does not ensure the stability of the factors.

Acute Disease↗
PubMed1993

Negative symptoms and emotional blunting in schizophrenic patients.

BACKGROUND: Emotional blunting and negative symptoms were explored as interchangeable concepts in evaluating schizophrenic patients. METHOD: We evaluated 115 consecutively admitted patients who had DSM-III-R schizophrenia. We performed a principal component analysis of Abrams and Taylor's Scale for Emotional Blunting (SEB) and Andreasen's Scale for the Assessment of Negative Symptoms (SANS) and correlated the subscales derived by factor analyses with demographic and clinical variables. RESULTS: Both scales contained subscales corresponding to poverty of affect and speech and inappropriate affect. The SEB also included an indifference subscale, whereas the SANS included avolition-anhedonia, asociality, and blocking subscales. Poor premorbid functioning was most strongly associated with poverty of affect and speech. Inappropriate affect and anhedonia-avolition-asociality were moderately correlated with poor response to treatment. CONCLUSION: Negative symptoms and emotional blunting are similar concepts, but they are not interchangeable. Flatness and inappropriateness appear to be different affective dimensions with different clinical correlations. Inappropriate affect, inattention, and blocking should not be considered negative symptoms.

Adult↗
PubMed1992

Influence of cannabis abuse on schizophrenic psychopathology.

A study was carried out on a group of 95 schizophrenic patients (DSM-III-R criteria) under the age of 35, 23 of whom were cannabis abusers in the past year. The objective of the study was to evaluate the effect of cannabis on positive and negative schizophrenic symptoms, evaluated using Andreasen's Scales for the Assessment of Positive and Negative Symptoms (SAPS and SANS). There were no statistically significant differences between the groups on the SAPS; the group of cannabis abusers had higher scores except for the delusions subscale. On the SANS nonabusers scored higher, with a significant difference on the alogia subscale. The results suggest that the consumption of cannabis by schizophrenic patients could attenuate negative symptoms, which would support the self-medication hypothesis of cannabis abuse.

Adolescent↗
PubMed1992

A polydiagnostic approach to self-perceived cognitive disorders in schizophrenia.

The relationship between the self-perceived cognitive disorders (SPCD) assessed using the Frankfurt Complaint Questionnaire (FCQ) and 21 definitions of schizophrenia was studied in a sample of 118 consecutively admitted patients. The FCQ total score was significantly associated (p < 0.05) with the presence of Schneider's, Yusin's and Present State Examination criteria of schizophrenia. A significant association, in this case negative, was also found between the FCQ total score and the presence of the DSM-III-R criteria of schizophrenia. The results suggest that the SPCDs are more associated with Schneider-related criteria than with chronic or deficit models of schizophrenia. It was also found that the female sex as well as the presence of insight were significantly associated with a greater number of SPCDs.

Adult↗
PubMed1992

Are there more than two syndromes in schizophrenia? A critique of the positive-negative dichotomy.

A sample of 115 DSM-III-R schizophrenics was studied by means of the SANS and SAPS. A factor analysis from the nine subscales and two symptoms (inappropriate affect and poverty of content) and a review of the previous factor analyses suggest that schizophrenic symptoms cannot be appropriately classified into positive and negative syndromes. The low internal consistency of the SAPS suggests that the positive symptoms are not a homogeneous syndrome. Our results fit better with Liddle's model of three syndromes (negative, delusion-hallucination and disorganisation syndromes). It is argued that we are far from a valid classification of schizophrenic symptoms and the positive-negative dichotomy appears to be an oversimplification.

Adolescent↗
PubMed1991

Premorbid personality and positive and negative symptoms in schizophrenia.

The relationship between premorbid personality and schizophrenic symptoms assessed by the Scales for the Assessment of Positive and Negative Symptoms was explored in 115 DSM-III-R schizophrenics. The frequencies of normal, schizoid-schizotypal and other DSM-III-R personality disorders were 44%, 39% and 17%. Affective flattening and alogia were significantly more frequently present and severe in the schizoid-schizotypal group than in the rest of the patients. There were no differences in positive symptoms. It is suggested that, in some cases, negative symptoms are merely the persistence or exacerbation of schizoid traits present prior to the emergence of schizophrenic symptoms. These results should be cautiously interpreted because the premorbid personality was diagnosed in a retrospective way and the negative symptoms were assessed cross-sectionally.

Adult↗