Imaging Biomarker Studies of Antipsychotic-Naïve First-Episode Schizophrenia in China: Progress and Future Directions

BACKGROUND AND HYPOTHESIS: Identifying biomarkers at onset and specifying the progression over the early course of schizophrenia is critical for better understanding of illness pathophysiology and providing novel information relevant to illness prognosis and treatment selection. Studies of antipsychotic-naïve first-episode schizophrenia in China are making contributions to this goal. STUDY DESIGN: A review was conducted for how antipsychotic-naïve first-episode patients were identified and studied, the investigated biological measures, with a focus on neuroimaging, and how they extend the understanding of schizophrenia regarding the illness-related brain abnormality, treatment effect characterization and outcome prediction, and subtype discovery and patient stratification, in comparison to findings from western populations. Finally, how biomarker studies should be conducted in the future was also discussed. STUDY RESULTS: Gray matter reduction has been most robust within temporo-frontal regions and cerebellum, whereas altered brain function has been most pronounced in cerebello-cortical connections and default mode network, each might be related to long-standing illness alterations and acute physiological alterations at measurement. By studying untreated patients, the progressive alterations in temporal and frontal regions and enlargements in bilateral putamen were found more likely effects of illness, not just treatment. Some of these changes were found with potential to predict clinical outcomes and differentiate biologically patient subgroups. CONCLUSIONS: Mostly with data-driven approaches, the studies from China are helping identify candidate imaging biomarkers in schizophrenia that are related to early-stage illness, treatment effects, and biological subgroup differentiation. Future work is needed to translate these biomarkers for clinical application.