Altered serum interleukin-4 and monocyte chemoattractant protein-3 levels are associated with generalized anxiety disorder: A case-control study

Abstract

Generalized Anxiety Disorder (GAD) is a long-term mental health disorder often linked with immune system dysregulation. While proinflammatory and anti-inflammatory cytokines are known to influence neuroinflammation, their specific roles in GAD remain less explored. This study investigates the association between serum levels of IL-4 and MCP-3 with GAD in a Bangladeshi population. This case-control study included 44 GAD patients and 44 healthy controls (HCs). Participants were examined using the GAD-7 scale. Serum IL-4 and MCP-3 levels were measured using ELISA. Data were analyzed using t-tests, Spearman’s correlation, and Receiver Operating Characteristic (ROC) curve analysis to assess diagnostic performance. GAD patients had significantly lower serum IL-4 (11.82±10.91 pg/ml) and higher MCP-3 (57.80±19.85 pg/ml) levels compared to HCs (IL-4: 24.51±15.36 pg/ml; MCP-3: 34.01±15.75 pg/ml; p<0.001). IL-4 levels showed a significant negative correlation with GAD-7 scores (r = -0.496, p<0.001), while MCP-3 showed a positive correlation (r = 0.544, p<0.001). ROC analysis indicated that MCP-3 had higher diagnostic accuracy (AUC = 0.848, sensitivity = 87.6%, specificity = 84.3%) compared to IL-4 (AUC = 0.782, sensitivity = 80.2%, specificity = 78.5%). Moreover, decreased IL-4 and elevated MCP-3 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.