Alterations of retinal microvascular density in patients with chronic obstructive pulmonary disease: A systematic review and meta-analysis.

BACKGROUND

The present study aimed to evaluate retinal microvascular alterations in patients with chronic obstructive pulmonary disease (COPD) utilizing optical coherence tomography angiography (OCTA).

METHODS

Pertinent articles comparing retinal vascular characteristics between eyes of COPD patients and healthy controls were systematically retrieved from PubMed, Embase, the Cochrane Library, and Web of Science from inception until June 2024. For continuous variables, mean differences with 95 % confidence intervals were calculated using Review Manager Version 5.4.

RESULTS

A total of six eligible studies encompassing 530 eyes (279 eyes in the COPD group and 251 eyes in the control group) were included in the meta-analysis. The analysis revealed a significant reduction in macular whole enface vessel density (VD) measured by OCTA in COPD patients compared to controls, with pooled mean differences of -2.16 (P = 0.04) for superficial VD and -2.93 for deep VD (P = 0.01). Additionally, combined values for parafoveal and perifoveal deep VD measured by OCTA were significantly lower in COPD patients than those observed in normal controls (MD= -2.31, P = 0.003; MD= -3.79, P = 0.03 respectively). Furthermore, pooled results indicated that radial peripapillary capillary (RPC) whole image VD, RPC inside disc VD, and RPC peripapillary VD detected by OCTA were markedly decreased in the COPD cohort compared to controls (MD= -1.68, P < 0.0001; MD= -2.14, P = 0.003; MD= -1.86, P = 0.0002 respectively).

CONCLUSION

Our findings indicate that individuals with COPD exhibit reduced vessel densities both within macular regions and at the optic nerve head area, thereby suggesting that OCTA metrics can serve as a potential auxiliary tool for diagnosing COPD due to their non-invasive nature and rapid assessment capabilities, especially if confounding diseases that can also affect retinal vessel densities are considered with care.