Psychosis Research Today is a free monthly online journal that collates and summarizes the latest research about Psychosis, including details on clinical depression, schizophrenia, bipolar disorder.

Does the dexamethasone suppression test reliably discriminate between psychotic and nonpsychotic major depression?: an exploratory analysis of potential confounds.

Gaudiano BA, Epstein-Lubow G, Miller IW

Department of Psychiatry and Human Behavior, The Warren Alpert Medical School of Brown University, Providence, Rhode Island, USA. Brandon_Gaudiano@brown.edu

Previous research has shown that psychotic major depression (PMD) is often associated with higher rates of nonsuppression on the dexamethasone suppression test (DST) compared with nonpsychotic major depression (NMD), suggesting the potential importance of cortisol hypersecretion in the psychotic subtype of the disorder. However, these patient groups also are known to differ from one another on a variety of other clinical variables, and there are numerous factors independent of diagnostic status known to affect the DST. Thus, we investigated possible confounds that could help account for the apparent DST abnormalities in PMD sometimes reported in past research. Hospitalized patients with PMD (n = 11) and NMD (n = 58) were compared on the DST and other clinical variables. As expected, PMD patients showed significantly higher rates of DST nonsuppression (55% vs. 24%; p = 0.04). However, PMD patients also had significantly higher levels of anxiety severity (p = 0.01). The higher rates of nonsuppression in the PMD group were attenuated when these patients were compared with a subsample of NMD patients matched on anxiety severity (55% vs. 55%). Implications for future research on biological markers of PMD are discussed.

Published 15 June 2009 in J Nerv Ment Dis, 197(6): 395-400.
Full-text of this article is available online (may require subscription).

Articles on Psychosis published 2 June 2009:

Familiality of novel factorial dimensions of schizophrenia.   Arch Gen Psychiatry, 66(6): 591-600.

CONTEXT: Factor analysis of the signs and symptoms of schizophrenia yields dimensional phenotypes that may relate to underlying genetic variation. Examination of familiality of factor scores can demonstrate whether they are likely to be of use in genetic research. OBJECTIVE: To produce a broader set of factorial phenotypes that are tested for familiality including core symptoms of schizophrenia and additional indicators of social, work, and educational dysfunction. DESIGN: The study used ... [Abstract] [Full-text]

Cognitive effects of antipsychotic drugs in first-episode schizophrenia and schizophreniform disorder: a randomized, open-label clinical trial (EUFEST).   Am J Psychiatry, 166(6): 675-82.

OBJECTIVE: Cognitive impairment, manifested as mild to moderate deviations from psychometric norms, is present in many but not all schizophrenia patients. The purpose of the present study was to compare the effect of haloperidol with that of second-generation antipsychotic drugs on the cognitive performance of patients with schizophreniform disorder or first-episode schizophrenia. METHODS: Subjects were 498 patients with schizophreniform disorder or first-episode schizophrenia who were randomly ... [Abstract] [Full-text]

Articles on Psychosis published 11 May 2009:

A disturbed sense of self in the psychosis prodrome: linking phenomenology and neurobiology.   Neurosci Biobehav Rev, 33(6): 807-17.

Interest in the early phase of psychotic disorders has risen dramatically in recent years. Neurobiological investigations have focused specifically on identifying brain changes associated with the onset of psychosis. The link between these neurobiological findings and the complex phenomenology of the early psychosis period is not well understood. In this article, we re-cast some of these observations, primarily from neuroimaging studies, in the context of phenomenological models of "the ... [Abstract] [Full-text]

Articles on Psychosis published 5 May 2009:

Prospective study of peer victimization in childhood and psychotic symptoms in a nonclinical population at age 12 years.   Arch Gen Psychiatry, 66(5): 527-36.

CONTEXT: Psychotic symptoms are commonly experienced in nonclinical populations of adolescents and adults and have been shown to be predictive of later schizophreniform disorders. Associations between adverse experiences in childhood and psychotic symptoms in adulthood have been demonstrated. OBJECTIVE: To examine whether peer victimization is associated with psychotic symptoms in a population-based sample of 12-year-olds. DESIGN: Prospective cohort study. SETTING: Assessment clinic for ... [Abstract] [Full-text]

Articles on Psychosis published 30 April 2009:

An association study of the neuregulin 1 gene, bipolar affective disorder and psychosis.   Psychiatr Genet, 19(3): 113-6.

OBJECTIVE: As evidence of partial aetiological overlap between bipolar affective disorder and schizophrenia is accumulating, it is important to determine whether genes implicated in the aetiology of schizophrenia play a role in bipolar disorder, and vice versa. As the neuregulin 1 (NRG1) gene has been associated with schizophrenia, we set out to investigate whether it is also associated with bipolar affective disorder, using a sample from Scotland, UK. METHODS: We tested four single nucleotide ... [Abstract] [Full-text]

Articles on Psychosis published 17 April 2009:

Psychosis as a disorder of reduced cathectic capacity: Freud's analysis of the Schreber case revisited.   Schizophr Bull, 35(3): 476-81.

Approximately 100 years ago, a prominent German public figure name Daniel Schreber wrote memoirs of his experiences in asylums. His case was diagnosed Dementia Praecox at times and Paranoia at others by his treaters. Freud analyzed Schreber's memoirs from the perspective of his "libido" theory of developmentally organized mental "cathexes" or ideational/emotional investments in self and others. Revisiting Freud's analysis of the Schreber case suggests that it may represent ... [Abstract] [Full-text]

Psychosis genetics: modeling the relationship between schizophrenia, bipolar disorder, and mixed (or "schizoaffective") psychoses.   Schizophr Bull, 35(3): 482-90.

As a result of improving technologies and greatly increased sample sizes, the last 2 years has seen unprecedented advances in identification of specific genetic risk factors for psychiatric phenotypes. Strong genetic associations have been reported at common polymorphisms within ANK3 and CACNA1C in bipolar disorder and ZNF804A in schizophrenia and a relatively specific association between common variation in GABA(A) receptor genes and cases with features of both bipolar disorder and ... [Abstract] [Full-text]

Life events and high-trait reactivity together predict psychotic symptom increases in schizophrenia.   Schizophr Bull, 35(3): 638-45.

Psychotic symptoms are exacerbated by stressful life events in schizophrenia patients as a group. Some individuals appear to be more vulnerable than others in this regard. This study tested whether schizophrenia patients are highly emotionally reactive compared with controls and whether the level of trait emotional reactivity in patients influences the degree to which they respond to life stressors with exacerbations of psychosis. Schizophrenic outpatients and nonpsychiatric controls were ... [Abstract] [Full-text]

© 2005-2009 Psychosis Research Today. All Rights Reserved.