Zhejiang University index (ZJU index) is an innovative composite metabolic marker combining triglycerides, fasting plasma glucose, body mass index, and transaminases. Existing literature demonstrates a clear association between metabolic state and depressed conditions. However, research exploring the relationship between overall metabolic condition and depression remain limited. This paper investigates the association between susceptibility to depressive symptoms and the ZJU index. Baseline data and laboratory values were collected from a cohort of 6244 individuals to calculate the ZJU index. Following a summary of the participants' baseline characteristics, adjustments for covariables were performed. Piecewise logistic regression analysis was employed to assess the association between the ZJU index and depression. Nonlinear relationships were analyzed using restricted cubic spline regression, while the receiver operating characteristic curve and area under the curve were employed to evaluate the ZJU index's advantage over single lipid metabolism indicators and a single metabolic index. Subgroup analyses were conducted based on demographics information, lifestyle factors, and chronic diseases. The piecewise logistic regression analysis revealed that individuals in the highest quartile (Q4) of the ZJU index had a significantly higher likelihood of depression compared to those in the lowest quartile (Q1) (OR = 1.4495, CI: 1.01–2.06, P = 0.046). A U-shaped nonlinear link between the ZJU index and depression (P-nonlinear = 0.03, inflection point = 35.47) was identified through restricted cubic spline analysis. Subgroup analysis revealed that the association between the ZJU index and depression was more pronounced in smokers and individuals with cardiovascular diseases. The area under the curve showed that in depression prediction, the ZJU index outperformed individual metabolic index. The ZJU index is strongly linked to a heightened chance of depression in American adults. Therefore, monitoring high ZJU index levels may contribute to the effective prevention of depression.

Hongru Li, Shijun Wang, Ming Sun, Sicen Wan, Xu Zhang, Gang Chen, Jiahe Wang, Xiang Li. The Relationship between the ZJU Index and Depression among American Adults: Insights from NHANES 2005–2018. Frontiers in Medical Science Research (2025), Vol. 7, Issue 6: 141-153. https://doi.org/10.25236/FMSR.2025.070617.

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