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Objective: To empirically identify schizophrenia neurocognitive subtypes and establish their association with clinical characteristics., Methods: Sustained attention, executive function, facial emotion recognition, verbal learning, and working memory tests were applied to 253 subjects with schizophrenia. We identified neurocognitive subtypes by a latent class analysis of the tests results. After, we made a search for the association of these subtypes with clinic characteristics., Results: We identified four neurocognitive subtypes: 1) “Global cognitive deficit”, 2) “Memory and executive function deficit”, 3) “Memory and facial emotion recognition deficit,” and 4) “Without cognitive deficit.” In comparison with the subtype “without cognitive deficit,” we found that the “memory and executive function deficit subtype” and the “global cognitive deficit subtype” had a higher frequency of male, unemployed, severe impairment, and adherence to treatment participants. However, in the “global cognitive deficit subtype” the differences were higher and there was also a lower frequency of past major depressive episodes (OR 0.39; 95%CI: 0.16 to 0.97). The “memory and facial recognition deficit subtype” had a higher probability of severe impairment (OR 5.52; 95%CI: 1.89 to 16.14) and unemployed (OR 2.43; 95%CI: 1.06 to 5.55) participants, but also a lower probability of past depressive episodes (OR 0.21; 95%CI: 0.07 to 0.66)., Conclusion: Our results suggest the existence of four neurocognitive subtypes in schizophrenia with a spectrum of dysfunction and severity. We found higher dysfunction in those with worse cognitive dysfunction, and higher affective psychopathology and less treatment adherence in those with less cognitive dysfunction.

Objective: To determine whether there are differences in verbal working memory amongst subjects with schizophrenia, their first degree relatives and controls, and to evaluate the influence of symptoms on these differences, as an initial step to assess whether this cognitive function is an endophenotype., Methods: We examined 197 cases with schizophrenia, 197 first degree relatives and 200 controls through psychiatric interviews and the Letters and Numbers Sequencing test (LNS). Performance was compared among the three groups adjusting for age, sex and education level. Adjustment for “negative symptoms” and “disorganization” was performed afterwards., Results: Subjects with schizophrenia showed lower performance in the LNS than their first degree relatives and the healthy controls; the effect sizes were 0.75 and 1.18 respectively. There was a small difference between relatives and controls (effect size =0.38). These differences were significant after adjustment for negative and disorganized symptoms, but the effect sizes became smaller: 0.26 for relatives vs. subjects with schizophrenia, 0.56 for controls vs. subjects with schizophrenia and 0.33 for relatives vs. controls. Among individuals with schizophrenia, performance in the LNS was not associated with disorder duration, disease onset age, antipsychotics, history of depressive episodes or substance use disorders., Conclusion: Results suggest verbal working memory may be considered as an endophenotype in schizophrenia.