Plasma G72 protein in schizophrenia: A comparative analysis of drug-naive schizophrenia patients, patients in acute exacerbation and healthy controls.

OBJECTIVES: Schizophrenia is a complex psychiatric disorder with an unclear etiopathogenesis. This study investigates the plasma G72 protein levels in drug-naive schizophrenia patients (DNS), those in acute psychotic episodes (AES), and healthy controls (HC). It also examines the correlation between the plasma G72 protein levels and Positive and Negative Syndrome Scale (PANSS) scores.

METHODS: The study included 138 schizophrenia patients (84 DNS, 54 AES) and 83 HCs. Plasma G72 protein levels were measured by ELISA. Statistical analyses, including log-transformation and correlation analysis, were conducted.

RESULTS: Schizophrenia patients had significantly lower plasma G72 levels than HCs (4.39 ± 5.38 vs. 8.06 ± 10.27 ng/mL, p < 0.001), while DNS and AES groups did not differ significantly. Log-transformed data confirmed these differences. Negative correlation was found between plasma G72 levels and age (r = -0.258, p = 0.02), PANSS-G (r = -0.249, p = 0.004), and total PANSS scores (r = -0.226, p = 0.008). ROC analysis showed poor discrimination between schizophrenia patients and controls (AUC: 0.587, p = 0.031).

CONCLUSIONS: This study's novel findings reveal that plasma G72 protein levels are significantly lower in schizophrenia patients and inversely correlated with age and symptom severity. However, the poor diagnostic accuracy observed in the ROC analysis suggests that G72 may not be a reliable biomarker for schizophrenia at this stage. These results underscore the need for further research to explore the potential clinical implications of these findings.