Podcasts about negative syndrome scale panss

The aim of this study was to develop a pharmacokinetic-pharmacodynamic (PKPD) model that quantifies the efficacy of haloperidol, accounting for the placebo effect, the variability in exposure-response, and the dropouts. Subsequently, the developed model was utilized to characterize an effective dosing strategy for using haloperidol as a comparator drug in future antipsychotic drug trials. The time course of plasma haloperidol concentrations from 122 subjects and the Positive and Negative Syndrome Scale (PANSS) scores from 473 subjects were used in this analysis. A nonlinear mixed-effects modeling approach was utilized to describe the time course of PK and PANSS scores. Bootstrapping and simulation-based methods were used for the model evaluation. A 2-compartment model adequately described the haloperidol PK profiles. The Weibull and E-max models were able to describe the time course of the placebo and the drug effects, respectively. An exponential model was used to account for dropouts. Joint modeling of the PKPD model with dropout model indicated that the probability of patients dropping out is associated with the observed high PANSS score. The model evaluation results confirmed that the precision and accuracy of parameter estimates are acceptable. Based on the PKPD analysis, the recommended oral dose of haloperidol to achieve a 30% reduction in PANSS score from baseline is 5.6 mg/d, and the corresponding steady-state effective plasma haloperidol exposure is 2.7 ng/mL. In conclusion, the developed model describes the time course of PANSS scores adequately, and a recommendation of haloperidol dose was derived for future antipsychotic drug trials.

The modern debate about schizophrenia began over 100 years ago, with Kraepelin’s description of “dementia praecox”. Despite this, central aspects of the disease remain mysterious and the disease itself is still associated with a high probability of an enduring limitation of the patient’s quality of life. While several conceptions of schizophrenia exist and are still under discussion, at least a provisional consensus regarding a valid measure of schizophrenia seems to have been reached: The Positive and Negative Syndrome Scale (PANSS) quantifies the current state of a person with schizophrenia by combining 30 different schizophrenia-associated symptoms into a single scale value. Even though the scale is widely used and is the measure of choice in many clinical trials, its psychometric properties are still the reason for serious confusion. In many research papers, one important fact about the PANSS is overlooked: it is an interval scale and, therefore, straightforward calculations of proportions are not appropriate. In other words, calculating simple percentage changes is incorrect and a prior scale correction is required. These kinds of calculations often appear in conjunction with responder analyses, as the definition of response is usually based on a predefined cut-off in terms of percent scale change. Two of the presented papers of this thesis are dealing with this urgent problem: using real data as well as simulated data sets, it is shown that ignoring the scale level of the PANSS can, in many cases, even lead to false test decisions concerning an examined treatment effect. Furthermore, an analysis of the problem’s urgency with regard to academic discussions, performed by way of a systematic study of literature in the highest-ranked journals dealing with schizophrenia, showed that incorrect calculations are widespread in the literature and that there is a strong need for a general clarification. As incorrectly calculated percent changes might be a reason for the published low cut-offs of response, as e.g. 20% or 30% cut-offs, the third included article in this thesis analyzes the association of correctly calculated percent changes in the PANSS with a generally measured therapy response. An equipercentile linking of percent PANSS changes and the improvement item of the Clinical Global Impression Scale (CGI) confirmed the choice of a considerably higher response cut-off of 50%. The combined conclusion of the three included articles is the emphasis on the need for a general methodological consensus in schizophrenia research. Valid and replicable research is only possible on the basis of generally accepted methods that rely on the correct application of scale theory in these studies.

Background: The aim of this study was to compare two measures of depression in patients with schizophrenia and schizophrenia spectrum disorder, including patients with delusional and schizoaffective disorder, to conclude implications for their application. Sampling and Methods: A total of 278 patients were assessed using the Calgary Depression Scale for Schizophrenia (CDSS) and the Hamilton Depression Rating Scale (HAMD-17). The Positive and Negative Syndrome Scale (PANSS) was also applied. At admission and discharge, a principal component analysis was performed with each depression scale. The two depression rating scales were furthermore compared using correlation and regression analyses. Results: Three factors were revealed for the CDSS and HAMD-17 factor component analysis. A very similar item loading was found for the CDSS at admission and discharge, whereas results of the loadings of the HAMD-17 items were less stable. The first two factors of the CDSS revealed correlations with positive, negative and general psychopathology. In contrast, multiple significant correlations were found for the HAMD-17 factors and the PANSS sub-scores. Multiple regression analyses demonstrated that the HAMD-17 accounted more for the positive and negative symptom domains than the CDSS. Conclusions:The present results suggest that compared to the HAMD-17, the CDSS is a more specific instrument to measure depressive symptoms in schizophrenia and schizophrenia spectrum disorder, especially in acutely ill patients. Copyright (c) 2012 S. Karger AG, Basel

Following the current hypothesis that acute schizophrenic psychotic illness is associated with a triatal ‘hyperdopaminergic state’, presynaptic integrity and dopamine transporter (DAT) density in first-episode, neuroleptic-naive schizophrenic patients was measured by single-photonemission- tomography (SPECT) and compared with that in healthy control subjects. A new SPECT-ligand for assessment of the striatal DAT, the Technetium-99m-labelled tropane TRODAT-1 ([99mTc]TRODAT-1), was used. Ten inpatients suffering from a first acute schizophrenic episode and 10 age- and sex-matched healthy control subjects underwent SPECT with [99mTc]TRODAT-1. On the day of SPECT, psychopathological ratings were performed with the Brief Psychiatric Rating Scale (BPRS), the Positive and Negative Syndrome Scale (PANSS) and Schedule for Assessment of Negative Symptoms (SANS). Patients had not previously received any neuroleptic or antidepressant medication. Mean specific TRODAT-1 binding in the striatum did not differ significantly between the patient and the age- and sex-matched control group (1.25 vs. 1.28). Variance was significantly higher in the patient group. The data obtained with the new ligand in first-episode, drug-naive schizophrenic patients are in line with the PET results from the group of Laakso et al. in a comparable patient sample. [99mTc]TRODAT-1 seems to be a valuable new SPECTligand in the evaluation of the presynaptic site of the striatal dopaminergic synapse in schizophrenia.