Association between arterial stiffness and choroidal vascular in type 2 diabetes: more pronounced in individuals aged 30 to 50 years.

PURPOSE: To investigate the association between systemic arterial stiffness and choroidal vascular parameters in patients with type 2 diabetes (T2D) using optical coherence tomography angiography (OCTA). METHODS: This study includes 177 eyes from 95 patients with T2D underwent clinical assessment and wide-field OCTA imaging (24 × 20 mm, TowardPi BMizar). Vascular density in superficial capillary plexus, choriocapillaris, and Sattler's and Haller's layers, and three-dimensional choroidal parameters, including choroidal vessel volume (CVV), stromal volume (CSV), and choroidal vascularity index (CVI), were acquired based on a 12 × 12 mm fovea-centered grid. Systemic arterial stiffness was assessed using brachial-ankle pulse wave velocity (baPWV). Associations were analyzed using correlation and regression models, including age-adjusted and age-stratified models. RESULTS: CVV and CSV showed significant negative correlations with age (p < 0.05) and baPWV (p < 0.05 in all regions except the central-nasal area). These reduction patterns were not observed in two-dimensional vascular parameters. These correlations lost statistical significance after adjusting for age. The age-stratified analysis revealed that baPWV was linear negatively associated with CVV and CSV in patients aged 30-50 years (p < 0.05 in most regions except the superior-temporal area), with maximum coefficients of - 0.14 and - 0.25, respectively. CONCLUSIONS: CVV and CSV are associated with systemic arterial stiffness in patients with T2D, particularly among those aged 30-50 years, indicating that choroidal parameters can serve as valuable biomarkers of systemic vascular health.