Journal of psychiatric research
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In the present study we investigated HPA axis activity in depressed patients treated with partial sleep deprivation (PSD) in order to identify endocrinological characteristics related to PSD responsiveness. Thirty-three drug-free patients (14 men, 19 women) suffering from major depression according to DSM-IV criteria were treated with PSD. Response to PSD was defined as a reduction of at least 30% according to the 6-item version of the Hamilton Depression Scale (6-HAMD). ⋯ Furthermore, a significant negative correlation between postdexamethasone cortisol levels and reduction in 6-HAMD scores after PSD could be established. However, there was no relationship between the cortisol stimulation following CRH challenge and response to PSD. Although the combined DEX/CRH challenge test is a more sensitive marker for HPA axis dysregulation in depression than the standard DST, the negative feedback of the HPA system reflected by the DST status is apparently more closely associated with response to partial sleep deprivation in major depressive disorder.
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Randomized Controlled Trial Clinical Trial
Intent-to-treat analysis for longitudinal clinical trials: coping with the challenge of missing values.
Drop-out is a common phenomenon in clinical trials of drug treatments involving longitudinal assessments for a fixed duration of follow-up. For these trials intent-to-treat (IT) analysis is usually preferred because time effects are seen in practice. The IT analysis mandates that all subjects randomized to a treatment arm should be included in the analysis. ⋯ The model used imputed doses from a plausible treatment scenario after drop-out and a 'propensity-adjusted' model where the imputations for the drop-outs were obtained from the adhering subjects with the same probability to remain on study (propensity) given the observed trajectory prior to withdrawal. Issues related to bias and efficiency of the estimates obtained by different analyses are discussed. We recommend a more widespread use of imputation models for the IT analysis.
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Clinical Trial
Validity of the Composite International Diagnostic Interview (CIDI) psychosis module in a psychiatric setting.
This study aimed to test the procedural validity of the psychosis module of the Composite International Diagnostic Interview (CIDI) by comparing it with diagnostic checklists completed by experienced clinicians. Seventy-five subjects were interviewed using the interviewer-administered version of the CIDI. Their clinician(s) then completed diagnostic checklists for DSMIV and ICD10 diagnoses of schizophrenia. ⋯ The CIDI showed good agreement with clinician checklist diagnoses when the criteria were based on questions asked of the subjects. When the interviewer was required to make judgement of behaviours, the agreement between the CIDI and the clinician checklists was lower, resulting in overall poor agreement between the CIDI and the clinician checklists. Suggestions for improving the validity of the psychosis module of the CIDI are made.
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For the past 20 years the most enduring explanation for schizophrenia has been the dopamine hypothesis, which proposes that the dopaminergic system is overactive in this widespread disease. Classically, the D2 receptor formed the core of the dopamine hypothesis since there was considerable evidence for elevations of D2 receptor levels in the brains of schizophrenic patients, and because these receptors served as the primary target in mediating antipsychotic effects of most neuroleptics. However, the dopamine D4 receptor has recently received particular attention in this context. ⋯ Nevertheless, investigations surrounding this receptor has been far from futile. The observations which support the idea that D4 might serve as a target for clozapine have significantly modified and extended our understanding of mechanisms underlying atypical antipsychotic treatment of schizophrenia, as well as the dopamine hypothesis for schizophrenia. Further characterization of this receptor may prove to be crucial in designing highly effective antipsychotic drugs with minimal contraindications.