Investigation of ocular microstructural changes according to disease severity in patients with chronic obstructive pulmonary disease

To investigate retinal nerve fibre layer (RNFL) thickness and vascular density alterations in the retina and optic disc in patients with chronic obstructive pulmonary disease (COPD).A total of 66 COPD patients and 54 age- and sex-matched healthy individuals were enrolled in this prospective cross-sectional study. The COPD patients were divided into 3 subgroups (mild, moderate, and severe COPD) based on spirometric parameters as per the Global Initiative for Chronic Obstructive Lung Disease guideline. RNFL thickness, foveal avascular zone area, and vessel density in the superficial capillary plexus, deep capillary plexus, and radial peripapillary capillary plexus were measured by optical coherence angiography and compared among groups.There was no significant difference between COPD patients and control individuals in terms of foveal avascular zone area or RNFL thickness (p = 0.891 and p = 0.896, respectively). Patients with severe COPD showed lower vessel density in the superficial capillary plexus compared with the other groups, but the difference was not significant (p > 0.05). In the deep capillary plexus, vessel density did not differ significantly among groups in the foveal region (p > 0.05) but was significantly lower in all parafoveal quadrants in the severe COPD group. Radial peripapillary capillary plexus vessel density also was lower in the severe COPD group, especially the peripapillary region (p = 0.044).Although COPD is primarily a lung disease, the eye seems to be among the tissues affected in its natural course. The effects are more pronounced in patients with severe COPD and in the deep capillary plexus and radial peripapillary capillary plexus.