Cognitive reserve profiles are associated with outcome in schizophrenia.

Cognitive reserve (CR), the brain's ability to cope with brain pathology to minimize symptoms, could explain the heterogeneity of outcomes in neuropsychiatric disorders, however it is still rarely investigated in schizophrenia. Indeed, this study aims to classify CR in this disorder and evaluate its impact on neurocognitive and socio-cognitive performance and daily functioning. A group of 106 patients diagnosed with schizophrenia was enrolled and assessed in these aereas: neurocognition, Theory of Mind (ToM) and daily functioning. A composite CR score was determined through an integration of the intelligence quotient and education and leisure activities. CR profiles were classified with a two-step cluster analysis and differences among clusters were determined with an analysis of variance (ANOVA). The cluster analysis was identified with three CR profiles characterized, respectively, by high, medium and low CR. ANOVA analysis showed significant differences on neurocognition, ToM and daily functioning between the clusters: people with higher CR reached significantly superior scores. This study suggests that greater general cognitive resources could act as a buffer against the effect of brain pathology, allowing patients to have a better cognitive performance, social outcome and quality of life.

Modeling the interplay of age at onset and sex on cognition in Schizophrenia.

Cognition remains one of the most critical features of the schizophrenia. A wide range of factors has been associated to neurocognition and, among these, sex and age of onset are two of the most consistently reported to influence the functional and cognitive outcome. This work aims to evaluate the effects of sex and age of onset and their interaction on cognition in 419 subjects with schizophrenia. Analyses of variance and analyses of covariance were performed to evaluate the effect of sex and age at onset on cognition. To model the possible interaction sex-onset on cognition, a separate slope regression analysis was performed. Analyses of variance showed significant differences between sexes for age and age at onset, both significantly higher among females, as well as for Executive Functions, with higher performance among males. When compared according to age at onset, late-onset patients performed better than both early- and intermediate-onset ones in Verbal Memory subtest, with a significant effect of length of illness. Moreover, early-onset patients showed a significantly lower IQ compared to both intermediate and late-onset ones, with no significant effect of length of illness. Finally, the separate slope regression revealed a significant interaction between sex and age at onset, with early-onset being associated to a worse global cognition only among male patients. Our finding of a significant sex-onset interaction effect on neurocognition sheds new light on the complex issue of cognitive heterogeneity in schizophrenia. Our data may help towards the development of personalized programs for preventive and rehabilitative purposes.