Abstract
PURPOSE: This study aims to evaluate potential associations between the weight-adjusted waist index (WWI) and all-cause and cardiovascular mortality in patients with chronic obstructive pulmonary disease (COPD). METHODS: Our investigation analyzed data from the National Health and Nutrition Examination Survey (NHANES, 1999-2018). From an initial cohort of 101,316 participants, we incorporated 1,396 qualified individuals with COPD. To investigate the relationship between WWI and mortality, we employed multiple analytical methods, including multivariate Cox proportional hazards regression, Kaplan-Meier survival analysis, subgroup stratification and restricted cubic spline (RCS) modeling. Additionally, the prognostic utility of WWI in predicting mortality risk was further assessed through time-dependent receiver operating characteristic (ROC) curve analysis. RESULTS: In fully adjusted models, the highest WWI tertile (T3) revealed higher risks for both all-cause mortality (HR: 1.82, 95% CI: 1.19-2.77, p=0.006) and CVD mortality (HR: 2.79, 95% CI: 1.48-5.26, p=0.002) compared to the lowest tertile (T1). RCS analyses revealed a strong and statistically significant linear association between WWI and mortality risk. These findings suggest that WWI may be a meaningful predictor of adverse outcomes in COPD. CONCLUSION: Our study demonstrates that higher WWI significantly predicts increased mortality risk in COPD patients, highlighting its prognostic value and suggesting potential utility for risk stratification in clinical practice.