Non-linear association of visceral adiposity index with incident diabetes: insights from a retrospective Japanese cohort study

Obesity, particularly visceral obesity, is a significant risk factor for the onset of diabetes mellitus. Visceral adiposity index (VAI) is a novel predictor of visceral obesity that aims to explore its relationship with the incident diabetes. This retrospective cohort study included 15,453 Japanese adults who did not have diabetes at the start of the study. Univariate analysis and Cox proportional hazards regression were employed to determine the independent link between VAI and diabetes. The Kaplan-Meier curve was used to investigate the difference in diabetes risk among subjects with varying VAI levels. Restricted cubic spline (RCS) curve was utilized to identify the non-linear relationship between VAI and diabetes risk. Elevated VAI values are linked to an increased risk of incident diabetes. Individuals with high VAI values had higher levels of blood pressure, blood glucose, blood lipids, and a higher prevalence of fatty liver, with a larger proportion of males and more severe smoking and alcohol consumption habits. On the contrary, individuals with exercise habits showed lower VAI values. The Cox regression analysis and Kaplan-Meier curves revealed a positive correlation between high VAI values and incident diabetes. Analyses of RCS curves also demonstrated a non-linear relationship. VAI is a valuable indicator for predicting diabetes risk and can be responsive to visceral obesity. The relationship between VAI and diabetes onset events is non-linear, and high VAI levels above 0.75 are associated with an increased risk of diabetes.