Meta-analysis of Placebo Response in Randomized Clinical Trials of Antipsychotic Drugs Using PANSS Focusing on Different Approaches to the Handling of Missing Data

A multinational case-control study comparing forensic and non-forensic patients with schizophrenia spectrum disorders: the EU-VIORMED project

BACKGROUND

The relationship between schizophrenia and violence is complex. The aim of this multicentre case-control study was to examine and compare the characteristics of a group of forensic psychiatric patients with a schizophrenia spectrum disorders and a history of significant interpersonal violence to a group of patients with the same diagnosis but no lifetime history of interpersonal violence.

METHOD

Overall, 398 patients (221 forensic and 177 non-forensic patients) were recruited across five European Countries (Italy, Germany, Poland, Austria and the United Kingdom) and assessed using a multidimensional standardised process.

RESULTS

The most common primary diagnosis in both groups was schizophrenia (76.4%), but forensic patients more often met criteria for a comorbid personality disorder, almost always antisocial personality disorder (49.1 v. 0%). The forensic patients reported lower levels of disability and better social functioning. Forensic patients were more likely to have been exposed to severe violence in childhood. Education was a protective factor against future violence as well as higher levels of disability, lower social functioning and poorer performances in cognitive processing speed tasks, perhaps as proxy markers of the negative syndrome of schizophrenia. Forensic patients were typically already known to services and in treatment at the time of their index offence, but often poorly compliant.

CONCLUSIONS

This study highlights the need for general services to stratify patients under their care for established violence risk factors, to monitor patients for poor compliance and to intervene promptly in order to prevent severe violent incidents in the most clinically vulnerable.

Meta-analysis of Dropout Rates in Placebo-Controlled Randomized Clinical Trials of Atypical Antipsychotics Assessed by PANSS

BACKGROUND AND OBJECTIVES

Subject dropout rates in placebo-controlled randomized clinical trials (RCTs) of antipsychotics are high. The missing values due to dropout represent a potential source of bias in clinical trials. We aimed to identify the potential factors affecting subject dropout in atypical antipsychotics RCTs by conducting a meta-analysis.

METHODS

Placebo-controlled RCTs for atypical antipsychotics using positive and negative syndrome scale (PANSS) as a psychiatric assessment scale were selected by database search. The potential factors affecting subject dropout, such as publication year, study design, and operational factors, were analyzed by meta-regression.

RESULTS

Forty-seven placebo controlled RCTs of atypical antipsychotics of which results were published between 1993 and 2018 were identified through the database search. In the multivariate meta-regression analysis, earlier publication year, older age of subjects, and longer study duration were significantly associated with high subject dropout rates in placebo-controlled clinical trials of atypical antipsychotics.

CONCLUSION

Subject dropout rates in clinical trials of atypical antipsychotics published between 1993 and 2018 year decreased over time. Study duration should be taken into consideration when designing future studies, where short study periods yet appropriate for evaluating the efficacy of new atypical antipsychotics are preferable. Additionally, previous medications and the degree of subject satisfaction with antipsychotics might affect subject dropout rate.