Association between visceral adiposity index and prostate cancer in men aged 40 years and older: a nationwide cross-sectional study.

Objectives: This study aimed to elucidate the correlation of Visceral Adiposity Index (VAI) with prostate cancer (PCa) among men aged 40 years and older in the United States.

Methods: Analysis included multivariate linear and logistic regression, smoothing curve fitting, and threshold effect evaluation using 2003-2010 National Health and Nutrition Examination Survey (NHANES) data. The stability of this relationship across demographic groups was assessed via subgroup analyses and interaction tests.

Results: Among 2,768 participants, those with elevated VAI displayed lower total prostate-specific antigen (tPSA) levels and reduced PCa risk. Each VAI unit elevation corresponded to a 0.075 ng/mL tPSA reduction [-0.075 (-0.145, -0.005)] and 18.8% PCa risk reduction [0.812 (0.687, 0.960)]. Top-quartile VAI individuals exhibited 0.282 ng/mL reduced tPSA [-0.282 (-0.557, -0.007)] and 49.7% reduced PCa risk [0.503 (0.282, 0.896)] relative to bottom-quartile counterparts. This inverse relationship was more pronounced in men ≥70 years. Moreover, VAI-tPSA in other races demonstrated a U-shaped pattern, with a 2.09 inflection point. At the same time, a Mexican American subgroup exhibited an inverted U-shape for VAI and PCa risk, with a 1.42 inflection point.

Conclusion: In men aged ≥70, VAI indicates an inverse PCa relationship. However, PSA-based PCa screening may be influenced in visceral-obese individuals aged <70.