Analysis of the Association between Retinal Artery Occlusion and Acute Ischaemic Stroke/ST-Elevation Myocardial Infarction and Risk Factors in Hungarian Patients

**Background:** Retinal artery occlusion (RAO) is a vascular disorder causing sudden, often irreversible visual loss due to occlusion of the central retinal artery or its branches. RAO shares risk factors with acute ischaemic stroke (AIS) and ST-elevation myocardial infarction (STEMI), including hypertension, diabetes, hyperlipidaemia, atrial fibrillation, and smoking. This study aimed to quantify the association between RAO and subsequent AIS/STEMI in Hungarian patients and to evaluate the combined effect of multiple cardiovascular risk factors.

**Methods:** This retrospective cohort study included 169 RAO patients (106 central RAO, 63 branch RAO) diagnosed between 2009 and 2019 at a Hungarian clinic. Data were collected from the clinic's electronic database and the Hungarian national electronic database. Inclusion criteria: adult patients with visual loss due to RAO within 1 week, confirmed by anamnestic data and characteristic fundus findings. Exclusion criteria: other ocular disorders, RAO associated with other retinal vascular disorders, suspected iatrogenic RAO, or inaccessible electronic documentation. A control group of 169 age- and gender-matched patients without retinal vascular disease was selected from hospital patients undergoing cataract surgery. For both groups, the presence of AIS, STEMI, and comorbidities (hypertension, type 1 diabetes, type 2 diabetes, atrial fibrillation, hyperlipidaemia, ischaemic heart disease) was recorded. Statistical analyses included Pearson's Chi-squared test, two-proportion Z-test, univariate logistic regression, and multiple logistic regression, all adjusted for age and gender. A p-value <0.05 was considered significant.

**Key Results:** The RAO group had a mean age of 64.18 ± 10.00 years (57.40% male). Compared to controls, RAO patients had significantly higher prevalence of AIS (23.67% vs. 2.96%, p<0.001) and STEMI (18.93% vs. 5.33%, p<0.001). Hypertension (85.80% vs. 73.37%, p=0.005) and hyperlipidaemia (33.14% vs. 12.43%, p<0.001) were significantly more common in the RAO group. Univariate logistic regression showed that RAO was associated with an 8.18-fold increased risk of AIS (OR: 8.18, 95% CI: 3.09–21.64, p<0.001) and a 3.10-fold increased risk of STEMI (OR: 3.10, 95% CI: 1.36–7.08, p=0.007). For STEMI, additional significant risk factors included type 1 diabetes (OR: 3.51, p=0.013), atrial fibrillation (OR: 2.35, p=0.030), hyperlipidaemia (OR: 2.30, p=0.023), and ischaemic heart disease (OR: 2.13, p=0.044). Multiple logistic regression revealed that the co-occurrence of RAO with hypertension increased the odds of AIS to 11.65 (95% CI: 4.44–30.55, p<0.001) and STEMI to 4.93 (95% CI: 2.24–10.85, p<0.001). The highest AIS risk was observed with RAO + hypertension + type 1 diabetes (OR: 25.11, 95% CI: 4.86–129.71, p<0.001). For STEMI, the highest risk was with RAO + hypertension + ischaemic heart disease (OR: 5.52, 95% CI: 2.10–14.53, p=0.001). Mortality due to cardio/cerebrovascular causes occurred in 23 RAO patients (13.61%).

**Clinical Implications:** RAO is a strong independent predictor of subsequent AIS and STEMI, with risk substantially amplified by coexisting cardiovascular risk factors. Ophthalmologists, often the first to evaluate RAO patients, should recognise this elevated risk and promptly refer patients for neurological and cardiological assessment. Early initiation of secondary prevention measures (e.g., antiplatelet therapy, risk factor management) may reduce the incidence of AIS/STEMI. The study highlights the need for multidisciplinary collaboration between ophthalmology, neurology, and cardiology to improve outcomes in this high-risk population.