The association between visceral fat metabolic score and stroke: mediation by declining kidney function

BACKGROUND: Stroke is a leading cause of mortality and disability worldwide. Metabolic Score for Visceral Fat (METS-VF), a metric of visceral obesity, has emerged as a novel predictor of metabolic diseases. However, its association with stroke remains unclear. This study investigates the relationship between METS-VF and the risk of stroke, as well as the potential mediating role of kidney function. METHODS: Data from the 1999-2020 National Health and Nutrition Examination Survey (NHANES) were analyzed, including 19,109 participants. Weighted logistic regression models were used to assess the association between METS-VF and stroke risk, with restricted cubic splines employed to explore their non-linear relationships. Mediation analysis examined the role of kidney function, measured by estimated glomerular filtration rate (eGFR). Subgroup and sensitivity analyses, including propensity score matching (PSM) and multiple imputations, were conducted to ensure the robustness of the findings. RESULTS: Higher METS-VF was significantly associated with an increased risk of stroke (OR = 2.78, 95% CI: 1.71-4.52, P < 0.001) after adjusting for multiple covariates. A non-linear relationship was observed, with stroke risk sharply increasing when METS-VF exceeded 7.00. Mediation analysis revealed that declining eGFR mediated 26.72% of the METS-VF-stroke association. Subgroup analysis indicated that the association was stronger in men (OR = 5.06, 95% CI: 2.80-9.12, P < 0.001) than in women (OR = 2.01, 95% CI: 1.03-3.92, P = 0.04, P for interaction = 0.01). Sensitivity analyses using PSM and multiple imputations confirmed the robustness of the results. CONCLUSIONS: METS-VF is independently associated with stroke risk, showing a non-linear relationship, with a potential mediating role of declining kidney function.