The association between weight-adjusted-waist index and abdominal aortic calcification in adults aged ≥ 40 years: results from NHANES 2013–2014

The negative effects of obesity on the cardiovascular health have drawn much attention. Weight-adjusted-waist index (WWI) has been proved to reflect weight-independent centripetal obesity. However, the association between WWI and abdominal aortic calcification (AAC) has not been reported before. Using data from National Health and Nutrition Examination Survey 2013–2014, we aimed to determine the relationship of WWI and AAC in adults aged ≥ 40 years. WWI was determined by dividing waist circumference by the square root of weight. AAC was measured by dual-energy X-ray absorptiometry and quantified by Kauppila scores. Severe AAC (SAAC) was defined as an AAC score > 6. We utilized weighed multivariable logistic regression and generalized additive model to explore the independent association between WWI and AAC. Threshold effects were further calculated by two-piecewise linear regression model. 3082 participants were enrolled in our analysis, of which 48.2% were male. WWI was positively associated with AAC scores (β = 0.34, 95% CI 0.05–0.63) and exhibited a nonlinear relationship with SAAC. On the left of the breakpoint (WWI = 11.11), WWI and SAAC were positively associated (OR = 2.86, 95% CI 1.40–5.84), while no such relationship was found on the right (OR = 1.07, 95% CI 0.77–1.48). Our findings indicated that WWI may serve as a simple biomarker of AAC in US adults aged ≥ 40 years.