Retinal Capillary Damage is Already Evident in Patients With Hypertension and Prediabetes and Associated With HbA1c Levels in the Nondiabetic Range

Objective: In a cross-sectional analysis we analyzed whether any change in capillary density in the retinal circulation could be detected in hypertensive patients in the pre-diabetic stage.

Methods: In this study, we assessed capillary density in the foveal (CDF) and parafoveal (CDPF) retinal area using optical coherence tomography-angiography in 62 hypertensive patients with normal glucose metabolism and 40 hypertensive patients with prediabetes.

Results: The CDF was lower in patients with prediabetes compared to patients with normal glucose metabolism. Moreover, we found a correlation between CDF and HbA1c and glucose levels for the entire cohort. In patients with HbA1c less than 6.5% (48 mmol/mol), CDF was lower in patients with Homeostatic Model Assessment for Insulin Resistance (HOMA-IR)≥2.5 compared to patients with HOMA-IR<2.5.

Conclusion: Our results demonstrate that hypertensive patients with prediabetes display retinal capillary changes and that an association with markers of glucose metabolism exists even within a non-diabetic HbA1c range.