Nonlinear association of the visceral adiposity index with migraine among the U.S adults from NHANES: a cross-sectional study

Background As a primary headache disorder impacting the neurovascular system, migraine has been linked to a higher risk in obese individuals relative to those with normal weight. Nonetheless, data regarding the association between central obesity and migraine are limited. The Visceral Adiposity Index (VAI) serves as an indicator of abdominal fat distribution and the functionality of adipose tissue. This study aims to examine the association between VAI and the risk of migraine in the adult U.S. population. Methods This research utilized data gathered from adult subjects during the 1999–2004 phase of the NHANES. Weighted multivariable logistic regression and smoothed curve fitting analyses were conducted to explore the potential associations between VAI and migraine. In addition, two-piecewise logistics regression models were used to calculate inflection points, we also conducted subgroup analysis, interaction tests to determine the consistency of findings. Results A total of 4503 participants(weighted mean age 46.35 years; 49.28% male) in this study, 868(19.28%) had a self-reported history of migraine. In the fully adjusted model, there is a 19% increased chance of getting migraine for every unit increase in the VAI after ln transformation(OR = 1.19, 95%CI:1.04–1.36). When VAI was converted from continuous variable into tertiles, participants in the highest VAI tertiles(T3) had a significantly 32% increased risk of migraine compared with those in the lowest tertile (OR = 1.32, 95%CI: 1.02–1.71). Furthermore,the multivariate smooth splines analysis demonstrated a non-linear relationship between VAI after Ln transformation and migraine ( P for nonlinearity < 0.05), with an inflection point of roughly 0.64. The subgroup analyses, adjusted for all covariates, were in line with the overall population findings, and also revealed interactions between stroke and the outcome within the subgroups. Conclusion The study revealed a non-linear relationship, suggesting that VAI, being a noninvasive measure of visceral adiposity, might be utilized for a straightforward assessment of migraine risk, thereby serving as an innovative marker.