Evaluation of retinal microvasculature according to stable chronic obstructive pulmonary disease severity and the correlation of pulmonary parameters with optical coherence tomography angiography findings

Purpose: To evaluate the retinal and optic disc microvascular changes according to disease severity in patients with stable chronic obstructive pulmonary disease (COPD), and the correlation of pulmonary parameters with optical coherence tomography angiography (OCTA) findings. Methods: Forty patients with COPD and 30 age- and sex-matched subjects (control group) were included in this cross-sectional prospective study. The COPD group was then divided into two subgroups according to GOLD classification and disease severity as mild-to-moderate COPD group (group 1) and severe COPD group (group 2). OCTA was performed with 6 mm x 6 mm sections for the macula and 4.5 mm x 4.5 mm sections for the optic disc. Foveal retinal thickness (FRT), peripapillary retinal nerve fiber layer (RNFL) thickness, and vessel density in different sections of the retina and optic disc were analyzed. Results: The mean ages, gender, intraocular pressures, peripapillary RNFL thickness, FRT, and optic disc vessel densities were similar among the groups. Compared to the control group and group 1, group 2 showed significantly lower mean foveal vessel density measurements in superficial and deep capillary plexus (P = 0.014 and P = 0.007, respectively). Cigarette packets/year, exacerbation per year, and Modified Medical Research Council showed significant negative correlations, whereas forced expiratory volume in 1 s (FEV1) and FEV1/forced vital capacity showed significant positive correlations with foveal vessel densities. Conclusion: COPD severity seems to have a negative effect on OCTA measurements. OCTA may reflect the severity of inflammation and hypoxia in COPD and may provide useful detailed information on the role of retinal vascular changes in the follow-up and progression of patients with COPD.