The Correlation Between Macular Vessel Density and Its Clinical Parameters in Diabetes Mellitus Type 2.

Purpose: To evaluate macular vessel density using clinical parameters in patients with type 2 diabetes mellitus (DM) without retinopathy.

Patients and methods: This cross-sectional study enrolled 32 participants (63 eyes) aged 40-60 years who met the inclusion criteria. Group 1 included 32 eyes of type 2 DM, whereas the rest had no DM. Ophthalmic examination was performed. Macular vessel density was measured using optical coherence tomography angiography (OCTA) with a 6 × 6 mm scan. Macular vessel density is correlated with patient age, HbA1c values, disease duration, and contrast sensitivity. The data were analyzed using Spearman's rank correlation and an independent t-test.

Results: Central (foveal area) macular vessel density in the diabetic group (5.36 ± 2.87) was significantly lower than that in healthy participants (7.82 ± 3.05) (p = 0.002). The whole macular vessel density (foveal and parafoveal areas) was also lower in the DM group than in the healthy subjects (15.76 ± 3.38 vs 17.18 ± 1.92) but the difference was not statistically significant (p = 0.070). The age of DM patients has correlated with central (r = -0.522; p = 0.002) and whole macular vessel density (r = -0.369; p = 0.038). HbA1c levels, diabetes duration, and contrast sensitivity were not correlated with macular vessel density.

Conclusion: Macular vessel density was lower in DM patients without retinopathy than in healthy subjects. In patients with DM, macular vessel density decreases with increasing age. We failed to find a correlation between macular vessel density and the HbA1c value, disease duration, or contrast sensitivity.