Abstract
Purpose :
Hydroxychloroquine (HCQ) is an antimalarial drug widely used by many specialties for the management of autoimmune diseases. Retinal toxicity with long term HCQ treatment is a major concern and risk factors have been established. Several recent studies detected microvascular changes in patients using HCQ without evident microangiopathy or retinopathy on ophthalmoscopy. In addition, Optical coherence tomography angiography (OCTA) may help to further elucidate the mechanisms of HCQ-induced retinal toxicity. We sought to conduct a systematic review and meta-analysis of the OCTA application to detect HCQ-induced microvascular alterations and further characterize them.
Methods :
PubMed, Scopus, Web of Science and Cochrane were systematically searched to November 1st, 2021, along with a manual search. Studies that used OCTA as a primary diagnostic method to evaluate the macular microvasculature of HCQ users were included. Meta-analyses of continuous outcomes were conducted using an inverse variance in the model. Primary outcomes were macular vessel density (VD) and foveal avascular zone (FAZ) at the superficial (SCP) and deep capillary plexus (DCP).
Results :
Of 159 screened articles, 8 were found eligible for qualitative and for quantitative analysis. Patients with high risk of HCQ-induced retinopathy due to the longer duration of treatment (> 5 years) presented lower VD in the retinal microvasculature than those with low risk in SCP (SMD -0.53 [-0.93, -0.12], P = 0.01 in fovea; SMD -0.44 [-0.73, -0.16], P = 0.002 in parafovea) and in DCP (SMD -0.53 [-1.01, -0.06], P = 0.03 in fovea) and a trend for wider FAZ in DCP (P = 0.06). When compared with healthy controls, HCQ users had lower VD in SCP (SMD -0.67 [-1.19, -0.15], P = 0.01 in fovea; SMD -0.74 [-1.40, -0.08], P = 0.03 in parafovea) and in DCP (SMD -0.85 [-1.59, -0.10], P = 0.03 in fovea) and presented a wider FAZ only in SCP (SMD 0.61 [0.03, 1.20], P = 0.05).
Conclusions :
Microvascular retinal changes were found in patients under HCQ treatment without any kind of retinopathy. These findings seem to precede structural and electrophysiologic changes, placing OCTA as a potential instrument for early detection of reversible retinopathy. In addition, these results support the idea of vasculopathy in the pathogenesis of HCQ-induced retinal toxicity.
This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.