http://nova.newcastle.edu.au/vital/access/services/Feed ${session.getAttribute("locale")} 5 Australian schizophrenia research bank: a database of comprehensive clinical, endophenotypic and genetic data for aetiological studies of schizophrenia http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:10415 Objective: This article describes the establishment of the Australian Schizophrenia Research Bank (ASRB), which operates to collect, store and distribute linked clinical, cognitive, neuroimaging and genetic data from a large sample of people with schizophrenia and healthy controls. Method: Recruitment sources for the schizophrenia sample include a multi-media national advertising campaign, inpatient and community treatment services and non-government support agencies. Healthy controls have been recruited primarily through multi-media advertisements. All participants undergo an extensive diagnostic and family history assessment, neuropsychological evaluation, and blood sample donation for genetic studies. Selected individuals also complete structural MRI scans. Results: Preliminary analyses of 493 schizophrenia cases and 293 healthy controls are reported. Mean age was 39.54 years (SD = 11.1) for the schizophrenia participants and 37.38 years (SD = 13.12) for healthy controls. Compared to the controls, features of the schizophrenia sample included a higher proportion of males (cases 65.9%; controls 46.8%), fewer living in married or de facto relationships (cases 16.1%; controls 53.6%) and fewer years of education (cases 13.05, SD = 2.84; controls 15.14, SD = 3.13), as well as lower current IQ (cases 102.68, SD = 15.51; controls 118.28, SD = 10.18). These and other sample characteristics are compared to those reported in another large Australian sample (i.e. the Low Prevalence Disorders Study), revealing some differences that reflect the different sampling methods of these two studies. Conclusion: The ASRB is a valuable and accessible schizophrenia research facility for use by approved scientific investigators. As recruitment continues, the approach to sampling for both cases and controls will need to be modified to ensure that the ASRB samples are as broadly representative as possible of all cases of schizophrenia and healthy controls. 2012-03-14T23:50:03.747Z ]]> A cross-sectional community study of serum iron measures and cognitive status in older adults http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:10312 The relationship of iron status with cognition and dementia risk in older people is contentious. We have examined the longitudinal relationship between serum ferritin and cognition in 800 community-dwelling Australians 60 years or older. Iron studies (serum iron, transferrin saturation, serum ferritin) were performed in 1994/5 and 2003/4 and clinical and cognitive assessments were conducted in 2003/4 for 800 participants of the Busselton Health Study. All participants completed the Cambridge Cognitive test (CAMCOG). Those with CAMCOG scores <84 underwent expert clinical review for cognitive disorders, including the Clinical Dementia Rating scale. Mean serum iron (18.3 μmol/l) and transferrin saturation (28.5%) in 2003/4 did not differ significantly from 1994/5 whereas mean serum ferritin decreased from 162 μg/l in 1994/5 to 123 μg/l in 2003/4, possibly reflecting aging or dietary changes. No relationships were observed between serum iron or transferrin saturation and presence or absence of dementia (p> 0.05). In participants without dementia (n=749), neither serum ferritin in 1994/5 or 2003/4 nor change in serum ferritin between these times was related to total CAMCOG or executive function scores, with or without adjustment for gender, age, National Adult reading test, or stroke history (all p> 0.05). No relationships were observed between ferritin and cognition for participants with possible or probable dementia (n=51). All participants identified as HFE C282Y homozygous or with serum ferritin >1,000 ng/ml had normal CAMCOG scores. We conclude abnormal body iron stores (low or high) are unlikely to have clinically significant effects on cognition or dementia risk in community-dwelling older people. 2012-03-06T05:10:08.582Z ]]> A multivariate electrophysiological endophenotype, from a unitary cohort, shows greater research utility than any single feature in the Western Australian family study of schizophrenia http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:1186 Background: Previous studies have found several electrophysiological endophenotypes that each co-varies individually with schizophrenia. This study extends these investigations to compare and contrast four electrophysiological endophenotype, mismatch negativity, P50, P300, and antisaccades, and analyze their covariance on the basis of a single cohort tested with all paradigms. We report a multivariate endophenotype that is maximally associated with diagnosis and evaluate this new endophenotype with respect to its application to genetic analysis. Methods: Group differences and covariance were analyzed for probands (n = 60), family members (n = 53), and control subjects (n = 44). Associations between individual endophenotypes and diagnostic groups, as well as between the multivariate endophenotype and diagnostic groups, were investigated with logistic regression. Results: Results from all four individual endophenotypes replicated previous findings of deficits in the proband group. The P50 and P300 endophenotypes similarly replicated significant deficits in the family member group, whereas mismatch negativity and antisaccade measures showed a trend. There was minimal correlation between the different endophenotypes. A logistic regression model based on all four features significantly represented the diagnostic grouping (χ2 = 32.7; p < .001), with 80% accuracy in predicting group membership. Conclusions: A multivariate endophenotype, based on a weighted combination of electrophysiological features, provides greater diagnostic classification power than any single endophenotype. 2010-04-27T06:38:25.410Z ]]> Genetic evidence for a distinct subtype of schizophrenia characterized by pervasive cognitive deficit http://nova.newcastle.edu.au/vital/access/manager/Repository/uon:1770 A novel phenotyping strategy in schizophrenia, targeting different neurocognitive domains, neurobehavioral features, and selected personality traits, has allowed us to identify a homogeneous familial subtype of the disease, characterized by pervasive neurocognitive deficit. Our genome scan data indicate that this subtype, which accounts for up to 50% of our sample, has a distinct genetic basis and explains linkage to chromosome 6p24 reported previously. If representative of other populations, the ratio of schizophrenia subtypes observed in our families could have a profound impact on sample heterogeneity and on the power of genetic studies to detect linkage and association. Our proposed abbreviated battery of tests should facilitate phenotype characterization for future genetic analyses and allow a focus on a crisply defined schizophrenia subtype, thus promoting a more informed search for susceptibility genes. 2010-04-27T06:10:37.348Z ]]>