Association Between Systemic Arterial Stiffness and Choroidal Vascular Resistance Assessed by Laser Speckle Flowgraphy in Diabetic Retinopathy

Purpose: This study aimed to investigate the association between peripapillary choroidal hemodynamics, as measured by laser speckle flowgraphy (LSFG), and systemic arterial stiffness, indicated by the cardio-ankle vascular index (CAVI), in patients with diabetic retinopathy (DR). Methods: In this retrospective cross-sectional study, 72 eyes from 72 patients with type 2 diabetes across DR stages were analyzed. Choroidal parameters, including mean blur rate (MBR; indicating blood flow), beat strength (BS; reflecting pulsatility), and the BS/MBR ratio (BOM; a resistance-related waveform index), were quantified in both temporal and nasal peripapillary regions. A stepwise multiple regression analysis was conducted to identify independent predictors of CAVI, considering age, sex, and LSFG parameters. Results: In univariate analyses, higher CAVI was significantly associated with increased choroidal pulsatility and resistance (P < 0.05). In the final exploratory stepwise multivariable model, age remained significantly associated with higher CAVI (β = 0.048, P = 0.020), while temporal BOM showed a borderline positive trend with CAVI (β = 2.719, P = 0.055). The model was statistically significant overall (adjusted R² = 0.326, P < 0.001). Conclusions: In patients with DR, age was the most robust determinant of CAVI. The retention of regional choroidal BOM parameters in the final exploratory stepwise model suggests a possible association whereby systemic pulsatile stress may influence choroidal hemodynamics, although these findings are exploratory and hypothesis-generating. Translational Relevance: LSFG-derived choroidal resistance (BOM) may help explore the ocular-systemic vascular connection in diabetes management.