Association between cognitive function, antioxidants, and clinical variables in Chinese patients with schizophrenia

Cognitive dysfunction is a prevalent and intricate manifestation of schizophrenia (SCZ) that may be associated with distinct clinical factors and the presence of antioxidants, which relationship is unclear. The study aimed to investigate cognitive function and its influencing factors in Chinese patients with SCZ.

A group of 133 patients with SCZ and 120 healthy controls (HCs) were recruited. The MATRICS Consensus Cognitive Battery (MCCB) was utilized to evaluate cognitive ability, and the Positive and Negative Syndrome Scale (PANSS) was used to assess clinical symptoms. Levels of plasma superoxide dismutase (SOD), serum albumin (ALB) and uric acid (UA) were assessed.

Compared with HCs, patients with SCZ exhibited lower cognitive performance as indicated by MCCB scores, including the dimensions of speed of processing, attention/vigilance, working memory, verbal learning, and visual learning. In the SCZ group, total PANSS scores were negatively associated with all MCCB dimensions (all p < 0.05), except for the attention/vigilance score. The PANSS-negative and PANSS-cognitive subscores were negatively associated with speed of processing, verbal learning, and visual learning scores (all p < 0.05). The PANSS-excited subscores showed a negative correlation with working memory and visual learning scores (all p < 0.05). ALB levels significantly decreased, and their UA and SOD levels were notably elevated compared to HCs (all p < 0.05). ALB levels and PANSS-negative factors were correlated with to speed of processing, working memory, and visual learning dimensions. SOD levels were independent contributors to the attention/vigilance dimension.

The cognitive function was decreased in SCZ. The degree of cognitive impairment was closely related to ALB, SOD levels and negative clinical symptoms.