Controversies surrounding the diagnosis of schizophrenia and other psychoses.
ABSTRACT The diagnosis of schizophrenia and other psychotic disorders in current psychiatric classifications identifies individuals who are severely ill but who have few clinical characteristics in common. The usual picture of psychotic patients is a mixture of mood and psychotic symptoms. Fortunately, clinicians do not base their therapeutic strategies exclusively on diagnosis, but also on symptom predominance. Thus, clinicians' treatments have been dimensional in nature for years, although, until recently, their psychiatric classifications had been mainly categorical. The main principle in psychosis classification has been the Kraepelinian dichotomy, despite its lack of enduring empirical validation. Without doubt, current psychiatric classifications have made great strides in reliability and clinical utility, although these advantages have not been enough to compensate for their shortcomings concerning validity. It has recently been suggested that the Kraepelinian dichotomy may be hindering progress in neurobiological research within psychosis. Mounting evidence is now fuelling a paradigm shift in the ongoing process of review of psychiatric classifications toward the introduction of complementary dimensional indicators of psychiatric categorical diagnoses. This new approach will allow us to understand psychosis as prototypical extremes of a severity continuum. The gradients of this continuum may begin with subtle expressions in the general population, continue with milder forms in relatives of psychotic patients and subclinical cases and finally reach the prototypical forms of psychosis at the other extreme. Future complementary dimensional indicators will require sound instruments capable of reflecting a multidimensional assessment of psychopathological symptoms, polydiagnostic interviews and the assessment of a wide range of nonsymptomatic domains. These new methods of assessment merging created by the shift toward a dimensional paradigm will be applied in the forthcoming new diagnostic criteria and may allow for a phenome-wide scanning for psychosis.
- SourceAvailable from: Manuel J Cuesta[Show abstract] [Hide abstract]
ABSTRACT: It was recently hypothesized by Lake (Schizophrenia Bulletin 2008; 34: 109-117) that Formal Thought Disorder (FTD) can be accounted for by a single disorder that is currently diagnosed as bipolar disorder. This study aimed to analyze the underlying dimensions of FTD and to examine to what extent FTD factors can be accounted for by clinical distractibility, attentional impairment, severity of mania, and familial liability of bipolar disorder and schizophrenia. Methods: Six hundred and sixty inpatients were assessed using a semistructured interview, and FTDs were assessed with the Thought, Language, and Communication scale. "Inattentiveness during Mental Status Testing" item of the Scale for the Assessment of Negative Symptoms scale and a composite mania score were used. The Family History-Research Diagnostic Criteria was used. FTD is a multidimensional construct comprised at least 5 dimensions: disorganization, verbosity, poverty of speech, idiosyncratic thinking, and blocking. Clinical distractibility loadings split in 2 factors, disorganization and blocking, but it did not load on the mania-related (verbosity) factor. Attentional disturbance was significantly associated with each FTD factor except for idiosyncratic thinking, and these associations were largely independent from the severity of mania. The associations of FTDs with mania and attentional disturbances were independent from each other. FTD factors were not significantly associated with familial liability to bipolar or to schizophrenia. Disorganization was the main FTD component. Distractibility was a core feature of FTD factors but it was not specifically accounted for by mania-related attentional impairment. The hypothesis of mutual interdependence between mania and attentional disturbance leading to FTDs could not be confirmed.Schizophrenia Bulletin 08/2011; 37(6):1136-46. · 8.80 Impact Factor
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ABSTRACT: Considering the widespread use of the Positive and Negative Syndrome Scale (PANSS) and its factors around the world in clinical trials, it is clearly necessary to perform a transcultural validation of the factor structure of the PANSS. The purpose of the present study was to examine the PANSS factor structure in a Korean sample of subjects with schizophrenia. A total of 150 outpatients were assessed using the PANSS and other clinical rating scales. Principal component analyses revealed five factors, i.e., negative, cognitive/disorganization, positive, excitement, and depression/anxiety dimensions, which accounted for 64.1% of the total variance. All five factors showed good internal consistency, suggesting that the reliability of the factors extracted was adequate. Significant correlations were found between the five components of the PANSS and the corresponding clinical rating scales. The results of the present study indicate that the five-factor model best fit the data from our patients and that it was validated transculturally. The factor structures should be further validated using various neurobiological methods to ultimately help in clarifying the heterogeneity and pathogenesis of symptomatology in schizophrenia.Psychiatry Research 02/2012; 197(3):285-9. · 2.68 Impact Factor
- Epidemiology and Psychiatric Sciences 09/2013; · 3.36 Impact Factor