Retinopathy Associated With Long-Term, Low-Dose of Hydroxychloroquine
According to a new study, a low dose of hydroxychloroquine over a 10- to 15-year period may lead to hydroxychloroquine retinopathy, which can result in permanent loss of vision.
An anti-malarial medication, hydroxychloroquine is also used to treat patients with systemic lupus erythematosus and other inflammatory diseases. Researchers examined the possible long-term risk for incident hydroxychloroquine retinopathy, which is an associated adverse effect of the medication.
Patients aged 18 years or older who received hydroxychloroquine over a period of 5 or more years were included in the study (n = 3325). The researchers assessed hydroxychloroquine doses given to patients from pharmacy dispensing records between 2004 and 2020.
Out of the total number of study participants, 81 patients developed hydroxychloroquine retinopathy, with 56 patients experiencing a mild case, 17 a moderate case, and eight a severe case. The researchers observed an overall cumulative incidence of 2.5% at 10 years and 8.6% at 15 years. Further, the researchers found that there was a lower incidence (2.7%) of hydroxychloroquine retinopathy when a lower dose was administered (5 mg/kg per day or lower) compared with a higher dose (21.6%, higher than 6 mg/kg per day). Additionally, a 5 to 6 mg/kg dose per day had an 11.4% cumulative incidence of retinopathy.
The researchers noted possible misclassifications of doses due to nonadherence to filled prescriptions may have limited the study’s findings.
“In this large, contemporary cohort with active surveillance retinopathy screening, the overall risk for hydroxychloroquine retinopathy was 8.6% after 15 years, and most cases were mild, the researchers concluded. “Higher hydroxychloroquine dose was associated with progressively greater risk for incident retinopathy.”
Reference:
Melles RB, Jorge AM, Marmor MF, et al. Hydroxychloroquine dose and risk for incident retinopathy. Ann Intern Med. Published online January 17, 2023. doi:10.7326/M22-2453