Assessing the risk of retinopathy in Indian patients using hydroxychloroquine for rheumatic and musculoskeletal diseases: A retrospective observational study

Abstract

Background: To assess the prevalence and risk factors associated with hydroxychloroquine (HCQ) retinopathy in patients with rheumatic and musculoskeletal diseases (RMD). Methods: Retrospective observational study was conducted on 984 patients using HCQ for RMD to detect prevalence of retinopathy by Humphrey visual field, spectral-domain optical coherence tomography, fundus autofluorescence test, and multifocal electroretinography (mfERG). Results: The patients' age ranged between 13 and 79 years and 85.8% were female. The prevalence of retinopathy was 13.5% in cases treated with HCQ. It was significantly more in the higher age group (>60 years) compared to lower age (<30 years), P = 0.033, but not significantly associated with gender, body mass index, hypertension, diabetes mellitus, hypothyroidism, and various RMD. In addition, retinopathy was not significantly associated with HCQ dose/day (P = 0.101), but was significantly associated with duration of HCQ treatment (12.2% prevalence with < 5 years treatment, while 19.8% with 5-10 years HCQ use; P = 0.017). A statistically significant difference was found between median duration of patients with and without retinopathy (36 vs. 30 months; P = 0.046). The mean cumulative HCQ dose in retinopathy patients was significantly high compared to nonretinopathy patients (283.79 g vs. 231.33 g; P = 0.006). Among the individual (possible retinopathy) tests, mfERG had the highest detection rate (11.4%) for retinopathy screening, whereas Humphrey visual field analyzer test (HVF) + mfERG had the highest detection rate among the combination (definite retinopathy) tests (12.8%). Conclusions: The high prevalence of retinal toxicity in patients with 1-5 years of HCQ therapy prompts the need for frequent ophthalmic screening, even before completion of 5 years of treatment.