Abstract
BACKGROUND: Growth differentiation factor 15 (GDF15) is a crucial biomarker in various physiological and pathological processes. While elevated GDF15 levels are linked to increased mortality risk, the role of DNA methylation (DNAm)-predicted GDF15 in predicting mortality has not been extensively studied. The purpose of the study is to investigate the association between DNAm-predicted GDF15 levels and all-cause and cardiovascular disease (CVD) mortality in a nationally representative cohort. METHODS: Data from NHANES 1999-2002 were analyzed. DNAm-predicted GDF15 levels were estimated using a regression model. Weighted multivariate Cox regressions were employed to assess the relationship between DNAm-predicted GDF15 and mortality outcomes. Restricted cubic splines were used to explore dose-response relationships, and subgroup analyses were conducted to enhance result reliability. RESULTS: Higher DNAm-predicted GDF15 levels were significantly associated with increased all-cause mortality risk (HR = 1.08, 95% CI: 1.02-1.15). Participants in the highest DNAm-predicted GDF15 tertile showed significantly higher all-cause mortality risk (HR = 1.56, 95% CI: 1.16-2.10) and a 2.52-fold increased risk of cardiovascular mortality (HR = 2.52, 95% CI: 1.22-5.19). Kaplan-Meier curves revealed decreasing survival probability with higher DNAm-predicted GDF15 tertiles. Restricted cubic spline analysis demonstrated a non-linear dose-response relationship between DNAm-predicted GDF15 levels and cardiovascular mortality. The positive correlation between DNAm-predicted GDF15 and mortality remained robust in most of subgroups. CONCLUSIONS: DNAm-predicted GDF15 independently predicts all-cause and cardiovascular mortality. This association persists across multiple models and stratified subgroups, supporting GDF15's value as a biomarker for mortality risk stratification. Future research should elucidate underlying biological mechanisms and evaluate GDF15's clinical utility in guiding mortality risk reduction interventions.