Predictive Role of Fixation Stability for Clinical Stages and Conversion in Schizophrenia and Its Correlation with Cognitive Function.

Background and hypothesis: Given that fixation stability is closely linked to cognition, we investigated fixation stability in patients at different stages of schizophrenia, its relationship with cognitive impairments, and its predictive role for conversion to psychosis.

Study design: Fixation stability was measured by bivariate contour ellipse area (BCEA), and cognition was assessed by the Measurement and Treatment Research to Improve Cognition in Schizophrenia Consensus Cognitive Battery for 75 patients with first-episode schizophrenia (FES), 75 patients with clinical high-risk (CHR) syndrome, and 75 healthy controls (HCs). After a 1-year longitudinal study, CHR follow-up outcomes were classified as CHR-converters and CHR-nonconverters. Diagnostic model for clinical stages and prediction model for conversion were constructed using logistic regression and Cox regression, respectively.

Study results: Patients exhibited fixation instability and cognition impairments compared to HC, with impairments increasing from CHR to FES. In CHR, BCEA negatively correlated with Measurement and Treatment Research to Improve Cognition in Schizophrenia Consensus Cognitive Battery scores, but this correlation was absent in FES. Diagnostic model effectively discriminated HC and FES, with an area under the receiver-operating characteristic curve of 0.914. Among 66 CHR followed up for 1 year, 13 have converted to schizophrenia, with a conversion rate of 19.70%. When divided into large and small BCEA groups (33 each), the conversion rate was 27.27% and 12.12%. Conversion prediction model achieved an area under the receiver-operating characteristic curve of 0.708.

Conclusions: Our results indicate that fixation instability worsens with schizophrenia progression, which is associated with cognitive impairments. Additionally, BCEA may serve as a biomarker for predicting conversion to psychosis.