Medicine (Baltimore). 2026 Jun 12;105(24):e49205. doi: 10.1097/MD.0000000000049205.
ABSTRACT
Biological aging has garnered increasing attention. Although the Zhejiang University (ZJU) index was developed to predict fatty liver disease, a condition associated with biological aging, direct evidence connecting it to biological aging remains limited. This study aimed to investigate the relationship between the ZJU index and biological aging. This retrospective cross-sectional study analyzed data from 1999 to 2018, utilizing nationally representative data from the National Health and Nutrition Examination Survey. Weighted multivariable linear and logistic regression models were used to assess the associations between the ZJU index and biological aging, adjusting for age, sex, race, education level, marital status, income-to-poverty ratio, body mass index, smoking and drinking status, physical activity, hypertension, diabetes mellitus, cardiovascular disease, and cancer. Restricted cubic spline regression assessed nonlinear relationships, along with trend tests and subgroup analyses to ensure the robustness of the results. A total of 12,486 participants were enrolled in the study, with a mean age of 46.70 ± 0.28 years, and 49.76% were male. The ZJU index showed significant positive associations with both the Klemera-Doubal method biological age (adjusted β = 0.42, 95% confidence interval: 0.37, 0.46) and accelerated aging risk (adjusted odds ratio = 1.20, 95% confidence interval: 1.17, 1.24). Similarly, a 1-unit increase in the ZJU index was linked to a 0.60-year rise in phenotypic age and a 10% increase in the accelerated aging risk. Restricted cubic spline analyses revealed a linear relationship between the ZJU index and Klemera-Doubal method biological age (P for nonlinearity = .804), but nonlinear associations with phenotypic age and both age acceleration measures (all P for nonlinearity < .05). The ZJU index showed a positive association with biological aging across most subgroups. Higher levels of the ZJU index were correlated with greater biological age and a higher likelihood of accelerated aging.
PMID:42299563 | DOI:10.1097/MD.0000000000049205