Biomedical subjects

Amalia Zarzuela

Publications and source records attributed to Amalia Zarzuela.

5 recordsLinked to original sources

PubMed2006

Insight dimensions and cognitive function in psychosis: a longitudinal study.

BACKGROUND: It has been reported that lack of insight is significantly associated with cognitive disturbance in schizophrenia. This study examines the longitudinal relationships between insight dimensions and cognitive performance in psychosis. METHODS: Participants were 75 consecutively admitted inpatients with schizophrenia, affective disorder with psychotic symptoms or schizoaffective disorder. Assessments were conducted at two time points during the study: at the time of hospital discharge after an acute psychotic episode and at a follow-up time that occurred more than 6 months after discharge. A multidimensional approach of insight was chosen and three instruments for its assessment were used: the Scale to Assess Unawareness of Mental Disorder (SUMD), three items concerning insight on the Assessment and Documentation in Psychopathology (AMDP) system and the Insight and Treatment Attitudes Questionnaire. The neuropsychological battery included a wide range of tests that assessed global cognitive function, attention, memory, and executive functions. RESULTS: After conducting adequate statistical correction to avoid Type I bias, insight dimensions and cognitive performance were not found to be significantly associated at cross-sectional and longitudinal assessments. In addition, baseline cognitive performance did not explain changes in insight dimensions at follow-up. Similar results were found in the subset of patients with schizophrenia (n = 37). The possibility of a Type II error might have increased due to sample attrition at follow-up. CONCLUSION: These results suggest that lack of insight dimensions and cognitive functioning may be unrelated phenomena in psychosis.

Adult↗

PubMed2006

The Val66Met polymorphism of the brain-derived neurotrophic factor gene is associated with risk for psychosis: evidence from a family-based association study.

Schizophrenia (SZ) is a prevalent and severe mental disorder. One of the most favored hypotheses for the etiology of SZ is the neurodevelopmental hypothesis. Brain-derived neurotrophic factor (BDNF), a member of the neurotrophin growth factor family, promotes the development, regeneration, and survival of neurons and has been linked to the neuropathology of SZ. The present study tested, in a sample of 94 nuclear families, the hypothesis that the BDNF gene Val66Met polymorphism is associated to SZ and its psychopathologic phenotype using a multidimensional symptom approach. Furthermore, considering a reported reduction of BDNF in the frontal cortex of patients with SZ, we studied the relationship between this polymorphism and prefrontal function. The transmission disequilibrium test (TDT) showed a preferential transmission of allele Val from heterozygous parents to the affected offspring (P = 0.002), suggesting a possible role of this gene in the vulnerability to SZ spectrum disorders. The findings remained essentially unchanged when the analysis was restricted to the subgroup of patients with SZ (P = 0.009) and when a multidimensional approach to the diagnosis was used. Quantitative transmission disequilibrium test (QTDT) analyses did not demonstrate a significant association between the prefrontal tests assessed (Wisconsin Card Sorting Test and Trail Making Test) and the transmission of the BDNF alleles. Our finding suggests that the investigated BDNF polymorphism plays an important role in the phenotype of psychosis, but not in the performance of tests of prefrontal cognitive functions analyzed in these patients.

Adult↗

PubMed2005

Dermatoglyphic anomalies and neurocognitive deficits in sibling pairs discordant for schizophrenia spectrum disorders.

The neurodevelopmental hypothesis of schizophrenia suggests that adverse genetic loading in conjunction with environmental factors early in fetal life causes a disruption of neural development, decades before the symptomatic manifestation of the disease. Neurocognitive deficits have been observed early on the course of schizophrenia, and their association with an early developmental brain lesion has been postulated. Dermatoglyphics have been analyzed in schizophrenia as markers of prenatal brain injury because of their early fetal ontogenesis and susceptibility to the same environmental factors that can also affect cerebral development. The aim of our study was to conduct a comparative examination of neurocognitive functions and dermatoglyphic variables in 89 sibling pairs discordant for schizophrenia spectrum disorders. Therefore, we investigated the association between these two markers to explore the prenatal origin of cognitive deficits in schizophrenia. The affected siblings were significantly impaired on all the cognitive variables assessed (Wisconsin Card Sorting Test, Trail Making Test and Continuous Performance Test) and had a greater number of dermatoglyphic anomalies. These results suggest the influence of intrauterine environmental factors in the siblings affected with schizophrenia. However, we did not detect a significant association between these two vulnerability markers in the schizophrenic patients, suggesting the role of genetic or late environmental factors in the origin of the neurocognitive deficits found in these patients.

Adult↗

PubMed2004

New evidence of association between COMT gene and prefrontal neurocognitive function in healthy individuals from sibling pairs discordant for psychosis.

OBJECTIVE: Using a sample of sibling pairs discordant for psychosis, the authors attempted to replicate the findings of previous studies suggesting that the functional genetic polymorphism Val158Met in the catechol O-methyltransferase (COMT) gene influences prefrontal cognitive function and increases the risk for schizophrenia. METHOD: Eighty-nine sibling pairs discordant for psychosis were genotyped for this polymorphism and were assessed with the Wisconsin Card Sorting Test, a measure of prefrontal function. Additionally, the preferential transmission of alleles for this polymorphism was analyzed in a sample of 89 nuclear families in order to examine the genetic association. RESULTS: In the healthy siblings, a linear relationship was seen in which performance on the Wisconsin Card Sorting Test was associated in an allele dosage fashion with COMT genotype (i.e., fewer perseverative errors with higher number of methionine alleles). However, this association was not observed in patients. Furthermore, no evidence of genetic association with psychosis was detected. CONCLUSIONS: These results seem to confirm the role of COMT genotype in the modulation of executive functions related to frontal lobe function in healthy individuals but not in schizophrenia patients.

Catechol O-Methyltransferase↗

PubMed2002

Neurological soft-signs in psychosis: threshold criteria for discriminating normal controls and for predicting cognitive impairment.

It is well established that psychotic patients obtain higher scores on neurological soft-sign (NSS) examinations than normal controls, and also that their cognitive performance is poorer. The aims of the present study were to find threshold criteria that distinguish between normal individuals and patients suffering from psychosis, and to investigate the predictive power of NSS for cognitive impairment. The sample was composed of 56 patients suffering from psychosis and 26 normal controls. Neurological assessment was carried out by means of the Neurological Evaluation Scale (NES), and neuropsychological assessment comprised executive, memory, visuospatial abilities, and attention tests. Receiver operating characteristic analysis was used to assess the diagnostic and predictive efficiency of NSS.A total score of 3 or over on the NES scale, or presence of three or more NSS, proved to be good threshold points for defining 'abnormality' in psychosis patients in comparison with normal controls. NSS presented greater predictive power for cognitive impairment than psychopathological dimensions. Moreover, an NES total score of 8 or higher or, to a lesser extent, the presence of six or more NSS in this scale seemed to be valid cut-off points for predicting severe cognitive impairment in individuals with psychosis.NSS were highly efficient predictors of the presence of severe cognitive impairment related to psychosis. However, their ability to discriminate between individuals with psychosis and normal controls was modest.

Adult↗