Gender Differences in the Predictive Value of Retinal Fractal Dimension for Cardiovascular and Cerebrovascular Diseases: A 10-Year Retrospective Cohort Study

AIM: This study aims to elucidate the predictive value of retinal fractal dimension（RFW）for Cardiovascular and cerebrovascular diseases(CCVD) and assess gender-specific variations, contributing to the formulation of targeted prevention strategies and early intervention measures. Methods: This retrospective cohort study analyzed health data from 4,917 individuals, selected from approximately 6530 annual attendees at our health check-up center, who had no baseline cardiovascular or cerebrovascular diseases in 2012 and consistently underwent annual examinations over a decade. The objective was to investigate the association between retinal fractal dimension and the risk of developing. Participants were categorized into quartiles based on their retinal fractal dimension, and the study employed Kaplan-Meier survival curves to compare cumulative incidence rates of cardiovascular diseases across these groups. Cox proportional hazards regression models were utilized to evaluate the relationship between retinal fractal dimension and cardiovascular risk, with dose-response dynamics further explored through restricted cubic spline analyses. Additionally, gender-based subgroup analyses were conducted to examine potential differences in the association between RFD and CCVD. Results: Among 4917 participants (mean age 52.98 ± 10.22 years; 67.76% male) followed for an average of 10.48 years, higher RFD was associated with healthier baseline profiles (lower BMI, blood pressure, glucose; higher physical activity; all P<0.001). Higher RFD quartiles were linked to significantly lower cardiovascular and cerebrovascular risk in the total population and in men (adjusted HRs for Q2–Q4: 0.584, 0.450, 0.479; all P<0.05). No significant association was found in women after adjustment. Dose-response analysis showed an inverse linear relationship between RFD and disease risk (P = 0.0001), with attenuation beyond an RFD of 1.27. ROC analysis showed moderate predictive value, with AUCs ranging from 0.671 to 0.720 over 10 years, peaking at year 5 (AUC = 0.720). Conclusions: Higher retinal fractal dimension is associated with better baseline health and lower cardiovascular and cerebrovascular risk, especially in men. RFD shows potential as a non-invasive biomarker for long-term risk prediction, though sex-specific differences warrant further investigation.