Abstract
OBJECTIVE: Retinal arteriosclerosis (RA) is a visible marker of early microvascular injury largely driven by cardiovascular risk factors. Insulin resistance, represented by the triglyceride-glucose (TyG) related indices, may serve as a key mediator linking cardiovascular health (CVH) to RA. METHODS: In this cross-sectional study of 755 healthcare staff aged ≥35 years, RA was defined as Keith-Wagener-Barker grade ≥1 on fundus photography, representing early subclinical retinal arteriolar changes. CVH was assessed using Life's Essential 8 (LE8). TyG-related indices, including TyG, TyG combined with body mass index (TyG-BMI), TyG combined with body roundness index (TyG-BRI), TyG combined with waist circumference (TyG-WC), and TyG combined with the waist-to-height ratio (TyG-WHtR), were calculated. Logistic regression and mediation analyses were performed to evaluate the associations of TyG-related indices with RA, and their mediating role in the LE8-RA relationship. RESULTS: RA was present in 159 participants (21.1%). Higher TyG-related indices were significantly associated with an increased odds of RA. In fully adjusted models, per SD increase in TyG was associated with a 40% higher odds of RA (OR = 1.40; 95% CI: 1.15-1.70; p = 0.001). Similar positive associations were observed for all obesity-related TyG indices. Higher LE8 scores were inversely associated with RA. Each 10-point increase in LE8 was associated with a 26% lower odds of RA (95% CI: 0.67-0.94; p < 0.001). RCS analyses indicated linear associations of TyG-related indices and LE8 with the risk of RA (all P-nonlinear > 0.05). Mediation analyses suggested that TyG-related indices statistically accounted for a substantial proportion of the inverse association between LE8 and RA, with mediated proportions ranging from 32.8 to 67.3%, consistent with a pattern of statistical full mediation. CONCLUSION: Higher TyG-related indices were associated with an increased risk of RA, whereas better CVH was associated with a lower risk. These findings underscore the importance of CVH in early retinal microvascular injury and support the potential role of TyG-related indices as simple risk markers.