Elevated serum cystatin C and IP-10 levels are associated with the pathophysiology and development of generalized anxiety disorder patients: A case-control study

Background Generalized anxiety disorder (GAD) is a long-term mental health disorder often linked with immune system dysregulation. According to recent research, neuroinflammation may be involved in the pathogenesis of GAD. However, specific roles of cystatin C and interferon-gamma inducible protein-10 (IP-10) in GAD remain less explored. This study aims to investigate the association between assessed serum cystatin C and IP-10 in GAD patients. Methods This case-control study included 100 GAD patients and 100 healthy controls (HCs). Participants were examined using the GAD-7 scale. Serum cystatin C and IP-10 levels were measured using ELISA. Data were analysed using t-tests, Spearman’s correlation, and Receiver Operating Characteristic (ROC) curve analysis to assess diagnostic performance. Results GAD patients had significantly elevated serum cystatin C and IP-10 levels compared to HCs (2.54 ± 0.16 vs. 1.62 ± 0.14 mg/L and 126.20 ± 10.18 vs. 88.54 ± 0.94 pg/mL; p < 0.001). Both cystatin C and IP-10 levels showed significant positive correlations with GAD-7 scores in patient group (cystatin C: r = 0.777, p < 0.001; IP-10: r = 0.279, p = 0.005), while elevated cystatin C and IP-10 levels indicated positive correlation with each other (r = 0.479, p < 0.001). ROC analysis indicated that cystatin C had higher diagnostic accuracy (AUC = 0.844, sensitivity = 74.0%, specificity = 83.0% at cut-off value of 2.02 mg/L) compared to IP-10 (AUC = 0.768, sensitivity = 71.4%, specificity = 80.5% at cut-off value of 96.40pg/mL). Conclusion Elevated serum cystatin C and IP-10 levels are significantly associated with GAD severity, suggesting an immune imbalance. These cytokines may serve as promising diagnostic biomarkers and therapeutic targets for GAD. Further longitudinal studies are recommended to inquire about the causal relationship and underlying mechanisms.