Association of negative symptoms with cognitive impairment in Chinese Han patients with chronic schizophrenia

Objective Cognitive impairment is an essential feature of schizophrenia; however, the relationship between clinical psychiatric symptoms with cognitive impairment is still unclear. Therefore, we aimed to assess cognitive deficits and the relationship between clinical symptoms and cognitive function in patients with chronic schizophrenia, which provide a reference guide for psychiatrists. Methods We compared the cognitive function in 312 schizophrenia inpatients and 397 healthy controls by using the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). The positive and negative symptom scale (PANSS) was used to assess the clinical symptoms of the patients. Results Analysis of covariance showed that the RBANS total and four index scores (all p < 0.001) were significantly lower in patients than healthy controls. After Bonferroni correction, Pearson correlation analysis showed that there was a significant negative association between PANSS negative symptom subscale and RBANS total score and all 5 domain scores (all p < 0.01). Further regression analysis showed that negative symptoms, age, age of onset, and antipsychotic dose were important independent predictors of cognitive deficits. Conclusions Our findings suggest that patients with chronic schizophrenia exhibit cognitive deficits compared with healthy people. Negative symptoms and some clinical variables are associated with cognitive impairment in patients with schizophrenia. KEYPOINTS This study indicates that patients with chronic schizophrenia have extensive cognitive impairment shown on RBANS except for the visuospatial/constructional domain. Cognitive impairment in patients is associated with age, negative symptoms, age of onset, and antipsychotic dose. There is a significant negative association between cognitive deficits and negative symptoms in patients with chronic schizophrenia. The results of this study need to be confirmed in future studies with longitudinal designs with a large and sex-balanced sample in first-episode drug naive patients with schizophrenia.