Association between the age-adjusted visceral adiposity index (AVAI) and gynecologic malignancies: a cross-sectional study based on NHANES data.

Background: Gynecologic cancers pose a significant threat to women's health worldwide, with obesity and related metabolic dysfunction recognized as key risk factors. Traditional measures, such as body mass index (BMI), fail to adequately capture visceral fat, which plays a crucial role in tumorigenesis through metabolic and inflammatory pathways. This study aims to assess the association between the age-adjusted visceral adiposity index (AVAI) and the risk of gynecologic cancers using data from the National Health and Nutrition Examination Survey (NHANES). Methods: This study analyzed a cross-sectional dataset from the NHANES [2007-2018], comprising 7,855 women, including 237 with gynecologic cancers (ovarian, endometrial, and cervical cancers) and 7,618 control participants without cancer. The AVAI was the main exposure variable. To control for potential confounders, such as age, race, educational level, the poverty-to-income ratio (PIR), smoking status, alcohol intake, hypertension, diabetes, and the BMI, multivariable logistic regression and generalized additive models were employed. The independent link between the AVAI and the risk of gynecologic cancers was examined. Additionally, subgroup analyses and restricted cubic spline functions were used to assess dose-response trends, while receiver operating characteristic (ROC) curves were generated to evaluate the discriminative performance of the AVAI. Results: Women with gynecologic cancers were older (P=0.02) and had higher waist circumference (WC), BMI, triglyceride (TG), and AVAI levels (P<0.001) than those in the control group. In the fully adjusted model I, each unit increase in the AVAI was associated with a 28.0% higher risk of gynecologic malignancies [odds ratio (OR) =1.280, 95% confidence interval (CI): 1.089-1.504, P=0.003]. Subgroup analysis showed a significant association with cervical cancer: each unit increase in AVAI resulting in a 30.9% higher risk in model I (P=0.02) and a 45.6% higher risk in model II (P=0.03), revealing a dose-response trend [Q2 (-8.7292 to -6.3966) vs. Q1 (<-8.7292): OR =2.085, P=0.007; Q3 (>-6.3966) vs. Q1: OR =2.974, P=0.02]. No statistically significant correlation was found between the AVAI and the risk of ovarian or endometrial cancers (P>0.05). ROC analysis showed that the area under the curve (AUC) of the AVAI for distinguishing women with and without gynecologic cancers was 0.807 (95% CI: 0.790-0.825, P<0.001). Conclusions: The AVAI, a composite index that integrates visceral fat distribution and metabolic function, was shown for the first time to be significantly associated with the risk of gynecologic malignancies, particularly cervical cancer, for which it demonstrated strong discriminative value. The study shows the superiority of the AVAI over traditional BMI in metabolic-inflammatory risk stratification, offering a new target for early identification and targeted interventions in gynecologic cancers. Future prospective cohort studies need to be conducted to verify causality and explore metabolic regulation strategies targeting the AVAI to reduce the risk of cancers.