2nd Edition of Diabetes and Endocrinology World Conference 2026

Abstract

Abstract

Background: Diabetic retinopathy (DR), a microvascular complication of diabetes mellitus (DM), is increasingly recognized as a potential marker of systemic vascular pathology. Carotid intima-media thickness (CIMT) is a validated surrogate marker for subclinical atherosclerosis. This study aimed to investigate the relationship between DR severity and CIMT in patients with type 2 diabetes mellitus (T2DM), exploring the interplay between microvascular and macrovascular complications.

Methods: A prospective observational study was conducted on 243 T2DM patients at King Abdulaziz Medical City, Riyadh, Saudi Arabia. Participants were stratified into three groups: proliferative DR (PDR), non-proliferative DR (NPDR), and no DR. Bilateral CIMT measurements were performed using high-resolution B-mode ultrasound, and DR severity was classified through fundoscopic examination and retinal imaging. Clinical, biochemical, and vascular data were collected and analyzed using non-parametric tests and Spearman’s correlation.

Results: Patients with PDR and NPDR were significantly older and had longer disease durations compared to those without DR (p < 0.001). CIMT values were significantly elevated in both DR groups, with median right CIMT of 0.075 mm (NPDR) and 0.070 mm (PDR) versus 0.060 mm in patients without DR (p < 0.001). Similar trends were observed in left CIMT. Carotid plaques and arterial wall changes were more prevalent in the DR groups (p < 0.001). Positive correlations were found between CIMT and disease duration, presence of carotid plaques, arterial wall changes, and reduced estimated glomerular filtration rate (eGFR). No significant correlations were observed between CIMT and HbA1c or fasting glucose.

Conclusion: This study demonstrates a significant association between DR and increased CIMT, supporting the hypothesis that DR reflects systemic macrovascular changes. The findings highlight the potential of DR as a non-invasive clinical marker for early cardiovascular risk stratification in T2DM patients. Integration of retinal and vascular assessments may enhance early identification of at-risk individuals and guide preventive interventions.

Keywords: diabetic retinopathy, carotid intima-media thickness, type 2 diabetes mellitus, subclinical atherosclerosis, cardiovascular risk, microvascular complications