Association between the weight-adjusted-waist index and circadian syndrome in findings from a nationwide study

Weight-adjusted-waist index (WWI) is an emerging parameter for evaluating obesity. We sought to ascertain the link between WWI and circadian syndrome (CircS). The study population consisted of 8275 eligible subjects who were included in the ultimate analysis from the NHANES 2011-2018. By using multivariable regression models, the association of WWI and CircS was analyzed. In subgroup analysis, we explored the relationship in different groups and tested the stability of the intergroup connection using interaction testing. To investigate whether WWI and CircS had a potential non-linear relationship, smooth curve fittings, and threshold effects tests were also constructed. In a multivariate linear regression model, WWI is significantly positively related to CircS (OR = 1.77, 95% CI 1.50-2.08). Through subgroup analysis and interaction testing, the stability of this positive association was also validated. It was further found that there was an inverted U-shaped association, with a turning point of 11.84, between WWI and CircS. Our findings supported a strong association between WWI values and CircS. Central obesity management is pivotal for preventing or alleviating CircS.