Prevalence and Risk Factors of Hydroxychloroquine Retinopathy in Rheumatic Patients with Dry Eye Symptoms

Purpose: Hydroxychloroquine is widely used for long-term treatment of rheumatic diseases, but the drug can trigger irreversible toxic retinopathy. We studied the prevalence of, and the risk factors for, hydroxychloroquine retinopathy in rheumatic patients with dry eye symptoms and we introduce a representative case.Metbods: We retrospectively studied a cohort of 133 rheumatological patients who had taken hydroxychloroquine for at least 12 months and who visited our ophthalmology clinic with dry eye symptoms from April 2016 to December 2021. Hydroxychloroquine retinopathy was diagnosed via fundus photography, spectral-domain optical coherence tomography, the Humphrey visual field test, autofluorescence fundus photography, and multifocal electroretinography. The principal outcomes were the prevalence of retinopathy at the first screening and the risk factors.Results: Of the 133 patients, hydroxychloroquine retinopathy was diagnosed in seven (5.2%) at the first screenings. The Mann-Whitney U-test revealed that older age; higher daily doses; longer dosing duration; greater cumulative doses; and higher daily and cumulative doses/kg were statistically significant in terms of retinopathy development. On multivariate logistic regression analysis, the average daily dose (odds ratio [OR] 6.02; 95% confidence interval [CI] 1.64-22.12, 100 mg increments) and duration of dosing (OR 3.39; 95% CI 1.19-9.62, 5 years increments) remained statistically significant (P = 0.021, P = 0.007 respectively)Conclusions: Ophthalmologists should enquire about any history of hydroxychloroquine therapy, and perform a retinal examination, when encountering dry eye in patients with rheumatic disease. Early detection of hydroxychloroquine retinopathy followed by discontinuation of hydroxychloroquine is the only way to prevent visual loss. High daily drug doses and long dosing durations are risk factors for retinopathy.