Retinal oculomics and risk of incident aortic aneurysm and aortic adverse events: a population-based cohort study

Background: The asymptomatic onset and extremely high mortality rate of aortic aneurysm (AA) highlight the urgency of early detection and timely intervention. The alteration of retinal vascular features (RVFs) can reflect the systemic vascular properties, and be widely used as the biomarker for cardiovascular disease risk prediction. Therefore, we aimed to investigate associations of RVFs with AA and its progression. Methods: In this prospective population-based cohort study, participants with eligible fundus images and without a history of AA at recruitment were included for analysis. A fully automated Retina-based Microvascular Health Assessment System was used to quantify multidimensional RVFs including the branching angle, caliber, complexity, density, length, and tortuosity. Univariable and multivariable Cox regressions were used to estimate the association of RVFs with the incidence of AA and aortic adverse events (AAE). Furthermore, propensity score matching was performed to mitigate the confounding effects of baseline characteristics. Results: During a median follow-up of 11.0 years, 306 incident AA (164 with abdominal AA and 108 with thoracic AA) and 48 incident AAE were documented. In the fully adjusted model, the retinal arterial branching angle (hazard ratio [HR] 0.87, 95% confidence interval [CI] 0.77 to 0.99) and the central tendency and variability of minimum venular caliber were significantly associated with the risk of incident AA (HR 1.13-1.15), while the venular minimum angular asymmetry (0.48, 0.30 to 0.77) was significantly associated with the incidence of AAE. Moreover, specific alterations of RVFs were observed in different AA subtypes (caliber in abdominal AA [HR 1.21]; caliber [HR 1.21-1.28], complexity, length, and tortuosity [HR 0.77-0.82] in thoracic AA). Similar results were obtained after propensity score-matched analysis, confirming the stability of these associations. Conclusions: We identified a significant association of certain RVFs with incident AA and AAE, implying that noninvasive, and convenient fundus photography could be a promising tool to facilitate the early detection of AA and subsequent preventative interventions.