A nationwide survey of hydroxychloroquine retinopathy presenting to the hospital eye service in the United Kingdom.

Between 1 in 1655 and 3215 (0.03-0.06%) long-term hydroxychloroquine users were diagnosed with retinopathy over the study period. We estimate that monitoring was available for 1.9-3.8% of long-term users, accounting for a lower than expected incidence. The high proportion of symptomatic retinopathy at diagnosis underlines the importance of monitoring to detect pre-symptomatic disease.