Sex differences in association between clinical correlates and cognitive impairment in patients with chronic schizophrenia

Schizophrenia is a heterogeneous disorder with sex differences in clinical manifestations and cognitive function. However, the nature of its sex-specific relationship between clinical manifestations and cognitive impairment remains equivocal. This study aimed to explore the sex differences in the association between cognitive function and clinical features of hospitalized patients with schizophrenia. A total of 251 schizophrenia patients (males/ females = 167/84) and 178 healthy controls (males/females = 84/94) were enrolled. Cognitive function was assessed through the Measurement and Treatment Research to Improve Cognition in Schizophrenia (MATRICS) Consensus Cognitive Battery (MCCB). The Positive and Negative Syndrome Scale (PANSS) was used to evaluate psychiatric symptoms in patients. Both male and female patients performed more impaired than their counterparts on all MCCB tests. However, only the scores of category fluency, attention and reasoning/problem solving of female patients were significantly lower than those of male patients. Multivariate regression analyses demonstrated that attention was independently associated with negative symptoms in female patients, and general psychopathology in male patients. Negative symptoms were also independently associated with verbal learning and memory and social cognition only in male patients, while general psychopathology was independently associated with symbol coding only in female patients. Our results suggest that there are noticeable sex differences in clinical features, cognitive impairment and their associations in schizophrenia patients. These sexspecific associations may provide useful information for future studies aimed at predicting and interfering with the outcome of schizophrenia from a sex perspective.