Investigation of early inner retinal layer changes in hydroxychloroquine users without evident retinopathy: A...

This study aimed to examine alterations in the macular ganglion cell complex (GCC), peripapillary retinal nerve fiber layer (RNFL), and macular vasculature prior to the manifestation of evident outer retinal toxicity in patients receiving hydroxychloroquine (HCQ).

The present comparative cross-sectional study included 42 patients with no evident retinopathy who were taking <5 mg/kg HCQ for rheumatoid arthritis and 41 age-matched healthy subjects. Both groups were analyzed using swept-source optical coherence tomography (SS-OCT), comprising macular GCC and peripapillary RNFL. Macular vessel density (MVD) analysis was conducted using OCT angiography.

The superior (p = 0.04), inferior (p = 0.01), and total GCC (p = 0.02) values were significantly lower in the study group than in the control group. However, the RNFL and MVD measurements demonstrated no statistically significant disparities in any of the quadrants between the two groups (p > 0.05). The subgroup analysis revealed that patients who had received HCQ for ≥ 8 years demonstrated significantly lower superior, inferior, and total GCC thickness, in addition to thinner RNFL values in superior quadrants when compared to patients who had received HCQ for a period of < 8 years and the control group.

The present study demonstrated that after eight years of HCQ use at recommended doses, significant thinning of the inner retinal layers was observed in eyes exhibiting no evident retinal toxicity. It may be beneficial to include an inner retinal layer assessment in individuals chronically using HCQ as part of a comprehensive ophthalmic screening process.