The mediating role of fasting plasma glucose and systolic blood pressure in the association between Chinese visceral adiposity index and carotid atherosclerosis: a cross-sectional study.

Visceral adipose tissue dysfunction is a key driver of cardiometabolic disease, yet the pathways linking it to atherosclerosis remain incompletely understood. This cross-sectional study included 6767 adults from a general health check-up population in Shanghai and investigated the association between the Chinese Visceral Adiposity Index (CVAI) and carotid atherosclerosis (CAS), as well as the mediating roles of systolic blood pressure (SBP) and fasting plasma glucose (FPG) using parallel mediation analysis. After full adjustment for confounders, each standard deviation (SD) increase in CVAI was associated with 37% higher odds of CAS (OR 1.37, 95% CI 1.26–1.49), demonstrating a significant linear dose-response relationship (P-overall < 0.001). Parallel mediation analysis revealed that SBP and FPG jointly mediated 59.2% of the total effect of CVAI on CAS, with SBP and FPG accounting for 36.0% and 23.2%, respectively, while a significant direct effect persisted (40.8%, P = 0.025). The association was consistent across all subgroups without significant interaction (all P-interaction > 0.05). This study quantifies the substantial parallel mediating roles of SBP and FPG in the CVAI–CAS association, highlighting the potential relevance of blood pressure and glycemic pathways in linking visceral adiposity to atherosclerosis risk.