This cross-sectional analysis used prospectively collected data from RECOGNISED, a European Union–funded multicenter observational study of individuals aged ≥65 years with type 2 diabetes. The study was published in the Primary Care Diabetes. Investigators assessed whether retinal microvascular parameters measured on color fundus photographs (CFP) were associated with mild cognitive impairment (MCI). Diagnosis of MCI was established using cognitive screening followed by detailed neuropsychological testing.

A total of 578 eyes from 307 participants were included; 182 had MCI and 125 had normal cognition. Median age was 72 years (IQR 69–77), 65% were male, and median diabetes duration was 19 years (IQR 12–24). CFP analysis quantified retinal vessel width, arteriovenous ratio, tortuosity, and fractal dimension. In multivariable logistic regression, lower arteriolar tortuosity was associated with MCI (OR 1.44; 95% CI 1.08–1.92), indicating higher risk with reduced tortuosity. The combined retinal microvascular parameters demonstrated an area under the curve (AUC) of 0.73 for identifying MCI.

Limitations include cross-sectional design precluding causal inference, strict inclusion criteria limiting generalizability, assessment confined to predefined macular regions, and potential spurious associations due to multiple testing.

Lower retinal arteriolar tortuosity was associated with MCI in this older type 2 diabetes cohort. Retinal microvascular parameters showed acceptable discrimination when combined with clinical characteristics.