Identifying gene-environment interactions in schizophrenia: Contemporary challenges for integrated, large-scale investigations

Recent years have seen considerable progress in epidemiological and molecular genetic research into environmental and genetic factors in schizophrenia, but methodological uncertainties remain with regard to validating environmental exposures, and the population risk conferred by individual molecular genetic variants is small. There are now also a limited number of studies that have investigated molecular genetic candidate gene-environment interactions (G 7 E), however, so far, thorough replication of findings is rare and G 7 E research still faces several conceptual and methodological challenges. In this article, we aim to review these recent developments and illustrate how integrated, large-scale investigations may overcome contemporary challenges in G 7 E research, drawing on the example of a large, international, multi-center study into the identification and translational application of G 7 E in schizophrenia. While such investigations are now well underway, new challenges emerge for G 7 E research from late-breaking evidence that genetic variation and environmental exposures are, to a significant degree, shared across a range of psychiatric disorders, with potential overlap in phenotype. \ua9 2014 The Author

Anticipated discrimination among people with schizophrenia.

The aim of this study was to evaluate the level of anticipated discrimination in people with schizophrenia (n = 732) from 27 countries in the International Study of Discrimination and Stigma Outcomes (INDIGO).Anticipated discrimination was assessed through four questions of Discrimination and Stigma Scale. Twenty-five individuals were identified at each site who were reasonably representative of all such treated cases within the local area.Sixty-four per cent of the participants reported that they had stopped themselves from applying for work, training or education because of anticipated discrimination. Seventy-two per cent of them reported that they felt the need to conceal their diagnosis. Expecting to be avoided by others who know about their diagnosis was highly associated with decisions to conceal their diagnosis. Those who concealed their diagnosis were younger and more educated. The participants who perceived discrimination by others were more likely to stop themselves from looking for a close relationship. Anticipated discrimination in finding and keeping work was more common in the absence than in the presence of experienced discrimination, and the similar findings applied to intimate relationships.This study shows that anticipated discrimination among people with schizophrenia is common, but is not necessarily associated with experienced discrimination

Cognitive functioning throughout adulthood and illness stages in individuals with psychotic disorders and their unaffected siblings

Important questions remain about the profile of cognitive impairment in psychotic disorders across adulthood and illness stages. The age-associated profile of familial impairments also remains unclear, as well as the effect of factors, such as symptoms, functioning, and medication. Using cross-sectional data from the EU-GEI and GROUP studies, comprising 8455 participants aged 18 to 65, we examined cognitive functioning across adulthood in patients with psychotic disorders (n\u2009=\u20092883), and their unaffected siblings (n\u2009=\u20092271), compared to controls (n\u2009=\u20093301). An abbreviated WAIS-III measured verbal knowledge, working memory, visuospatial processing, processing speed, and IQ. Patients showed medium to large deficits across all functions (ES range\u2009=\u2009-0.45 to -0.73, p\u2009<\u20090.001), while siblings showed small deficits on IQ, verbal knowledge, and working memory (ES\u2009=\u2009-0.14 to -0.33, p\u2009<\u20090.001). Magnitude of impairment was not associated with participant age, such that the size of impairment in older and younger patients did not significantly differ. However, first-episode patients performed worse than prodromal patients (ES range\u2009=\u2009-0.88 to -0.60, p\u2009<\u20090.001). Adjusting for cannabis use, symptom severity, and global functioning attenuated impairments in siblings, while deficits in patients remained statistically significant, albeit reduced by half (ES range\u2009=\u2009-0.13 to -0.38, p\u2009<\u20090.01). Antipsychotic medication also accounted for around half of the impairment in patients (ES range\u2009=\u2009-0.21 to -0.43, p\u2009<\u20090.01). Deficits in verbal knowledge, and working memory may specifically index familial, i.e., shared genetic and/or shared environmental, liability for psychotic disorders. Nevertheless, potentially modifiable illness-related factors account for a significant portion of the cognitive impairment in psychotic disorders