Visceral adiposity index (VAI) association with suicidal ideation among U.S. adults: a cross-sectional study using NHANES 2005-2018 data.

Background and objective: Suicidal ideation (SI) poses a significant public health challenge, and understanding its predictors, especially modifiable factors like visceral obesity, is essential for prevention. The purpose of this study is to investigate the association between the visceral adiposity index (VAI) and suicidal ideation (SI) among adults in the United States.

Methods: A cross-sectional study using NHANES data from 2005-2018 included adults aged 18 and above with complete SI and VAI data. Suicidal thoughts were evaluated using item 9 from the Patient Health Questionnaire-9 (PHQ-9), while VAI was calculated using gender-specific formulas based on waist circumference, body mass index (BMI), total triglycerides (TG), and high-density lipoproteins (HDL-C). Multivariate logistic regression analysis was implemented after adjusting for several factors to assess the relationship between VAI and SI. Additionally, subgroup analysis and interaction testing were employed to investigate the consistency of this relationship with other demographic parameters.

Result: Our study included a cohort of 15,830 participants, of whom 3.59% exhibited signs of suicidal ideation. Following multivariate logistic regression analysis, we observed a significant positive association between VAI and SI (odds ratio [OR] = 1.03; 95% CI 1.01, 1.04; P = 0.0057), which remained significant after adjusting for various confounding factors. Moreover, utilizing a two-segment linear regression approach, we uncovered a nonlinear relationship between VAI and SI, demonstrating a U-shaped pattern with a critical point at 5.28.

Conclusion: Elevated levels of VAI were consistently associated with an increased probability of SI, and this association remained consistent across various demographic variables. Level of evidence Level V-cross-sectional observational study.