Correlation between two novel visceral fat indicators and all-cause mortality among patients with asthma

Asthma prevalence is associated with metabolic score for visceral fat (METS-VF) and weight-adjusted waist index (WWI). Nonetheless, whether their associations with all-cause mortality differ in magnitude or predictive accuracy, especially in asthma patients, has not been empirically established. Our study examines data derived from the National Health and Nutrition Examination Survey (NHANES) database, spanning the years 1999 to 2018, and encompasses a sample of 1,260 adult asthma patients. To examine the relationship between METS-VF and WWI in predicting all-cause mortality among asthma patients, we utilized multivariable Cox proportional hazards regression analysis, Kaplan-Meier survival curves, restricted cubic spline models, as well as receiver operating characteristic (ROC) curves. Within a median follow-up duration of 95 months, 188 all-cause deaths were recorded. An increase of 1 unit in METS-VF was associated with a hazard ratio (HR) of 2.01 for all-cause mortality, whereas for WWI, the HR was 1.46. Additionally, restricted cubic spline analyses showed no statistically significant non-linear relationships between the two indicators and all-cause mortality. In weighted multivariable Cox regression models, HRs were notably elevated in the highest METS-VF and WWI groups compared to the reference groups. The time-dependent ROC curves demonstrated that WWI had slightly higher AUC values than METS-VF in predicting all-cause mortality (5-year: 0.829 vs. 0.819; 10-year: 0.861 vs. 0.860; 15-year: 0.866 vs. 0.864). Elevated levels of METS-VF and WWI are positively associated with an increased risk of all-cause mortality among asthma patients. Additionally, METS-VF exhibited relatively lower discriminatory ability for predicting all-cause mortality compared to WWI. Notably, this study did not account for potential confounding by asthma severity markers (e.g., lung function, medication use), which may influence mortality risk.