Normal levels of prepulse inhibition in the euthymic phase of bipolar disorder.

BACKGROUND:Deficits in prepulse inhibition (PPI) of the acoustic startle response have been suggested as a potentially useful endophenotype for schizophrenia spectrum disorders and may explain certain symptoms and cognitive deficits observed in the psychoses. PPI deficits have also been found in mania, but it remains to be confirmed whether this dysfunction is present in the euthymic phase of bipolar disorder.METHOD: Twenty-three adult patients with DSM-IV bipolar disorder were compared to 20 controls on tests of acoustic startle reactivity and PPI of the startle response. Sociodemographic and treatment variables were recorded and symptom scores assessed using the Hamilton Depression Inventory and the Young Mania Rating Scale.RESULTS:Overall, the patient and control groups demonstrated similar levels of startle reactivity and PPI, although there was a trend for the inter-stimulus interval to differentially affect levels of PPI in the two groups.CONCLUSIONS: In contrast to bipolar patients experiencing a manic episode, general levels of PPI were normal in this euthymic sample. Further studies are required to confirm this finding and to determine the mechanisms by which this potential disruption/normalization occurs. It is suggested that an examination of PPI in a high-risk group is required to fully discount dysfunctional PPI as a potentially useful endophenotype for bipolar disorder.

Cognitive functioning in subjects with recent-onset psychosis from a low-middle-income environment: Multiple-domain deficits and longitudinal evaluation

Cognitive deficits are a key feature of recent-onset psychosis, but there is no consensus on whether such deficits are generalized or confined to specific domains. Besides, it is unclear whether cognitive deficits: a) are found in psychotic patients in samples from outside high-income countries; and b) whether they progress uniformly over time in schizophrenia and affective psychoses. We applied 12 tests organized into eight cognitive domains, comparing psychosis patients (n = 56, time from initial contact = 677.95+/-183.27 days) versus healthy controls (n = 70) recruited from the same area of Sao Paulo, Brazil. Longitudinal comparisons (digit span and verbal fluency) were conducted between a previous assessment of the subjects carried out at their psychosis onset, and the current follow-up evaluation. Psychosis patients differed significantly from controls on five domains, most prominently on verbal memory. Cognitive deficits remained detectable in separate comparisons of the schizophrenia subgroup and, to a lesser extent, the affective psychosis subjects against controls. Longitudinal comparisons indicated significant improvement in schizophrenia, affective psychoses, and control subjects, with no significant group-by-time interactions. Our results reinforce the view that there are generalized cognitive deficits in association with recent-onset psychoses, particularly of non-affective nature, which persist over time. (C) 2009 Elsevier Ireland Ltd. All rights reserved.

Cognitive deficits in first-episode psychosis: A population-based study in Sao Paulo, Brazil

Background: Studies conducted in high-income countries have reported significant cognitive deficits in first on set schizophrenia subjects relative to asymptotic controls, and it has been suggested that the severity of such deficits could be directly related to the duration of untreated psychosis (DUP). It is relevant to conduct similar studies in developing countries, given the supposedly better outcome for schizophrenia patients living in the latter environments.

Methods: We applied verbal fluency and digit span tests to an epidemiological-based series of patients with first-onset psychoses (n = 179) recruited in the city of Sao Paulo, and compared the findings with those from non-psychotic control subjects randomly selected from the same geographical areas (n=383).

Results: Psychosis subjects showed lower scores on the three tests relative to controls, with greatest between-group differences for the backward digit span task (p < 0.0001). There were no significant differences between subjects with affective and schizophreniform psychosis. Cognitive performance indices were negatively correlated with the severity of negative symptoms, but showed no relation to DUP.

Conclusion: We found significant cognitive deficits in patients investigated early during the course of psychotic disorders in an environment that is distinct from those where the subjects investigated in previous studies have been drawn from. We found no support to the hypothesis of an association between greater cognitive deficits and a longer DUP. (c) 2006 Published by Elsevier B.V.

Premorbid IQ in patients with functional psychosis and their first-degree relatives

Numerous studies have found deficits in premorbid IQ in schizophrenic patients, but it is not clear whether this deficit is shared by (a) patients with other functional psychoses, and (b) relatives of these patients. Ninety-one schizophrenic patients, 66 affective psychotic patients (29 schizoaffective and 37 manic or depressed), and 50 normal control subjects were administered the National Adult Reading Test (NART) which provides an estimate of premorbid IQ. The NART was also completed by 85 first-degree relatives of schizophrenic patients and by 65 first-degree relatives of affective psychotic patients. After adjustments were made for sex, social class, ethnicity and years of education, schizophrenic patients had significantly lower premorbid IQ than their relatives, the affective psychotic patients and controls. Manic and depressed patients had significantly lower NART scores than their first-degree relatives, but schizoaffective patients did not, and neither group differed significantly from controls. There was no significant difference in premorbid IQ between patients who had experienced obstetric complications (OC +) and those who had not (OC -). Both OC + and OC - schizophrenic patients differed significantly from their relatives, but the disparity was greatest between OC + patients and their relatives. Relatives of OC + schizophrenic patients had significantly higher IQ than relatives of OC - schizophrenic patients. (C) 2000 Elsevier Science B.V. All rights reserved.

Volume reduction of the corpus callosum and its relationship with deficits in interhemispheric transfer of information in recent-onset psychosis

The present study aimed to investigate the presence of corpus callosum (CC) volume deficits in a population-based recent-onset psychosis (ROP) sample, and whether CC volume relates to interhemispheric communication deficits. For this purpose, we used voxel-based morphometry comparisons of magnetic resonance imaging data between ROP (n = 122) and healthy control (n = 94) subjects. Subgroups (38 ROP and 39 controls) were investigated for correlations between CC volumes and performance on the Crossed Finger Localization Test (CFLT). Significant CC volume reductions in ROP subjects versus controls emerged after excluding substance misuse and non-right-handedness. CC reductions retained significance in the schizophrenia subgroup but not in affective psychoses subjects. There were significant positive correlations between CC volumes and CFLT scores in ROP subjects, specifically in subtasks involving interhemispheric communication. From these results, we can conclude that CC volume reductions are present in association with ROP. The relationship between such deficits and CFLT performance suggests that interhemispheric communication impairments are directly linked to CC abnormalities in ROP. (C) 2010 Elsevier Ireland Ltd. All rights reserved.