The 2016 AAO Hydroxychloroquine Dosing Guidelines Put Short, Obese Patients at Risk

Abstract Objective/ Purpose : The prevalence of obesity has been increasing for 60 years implying the need to reassess the risk of hydroxychloroquine retinopathy (HR) in obese women using American Academy of Ophthalmology (AAO) 2016 guidelines. Design Cross sectional study Subjects The medical records of 64 cases of HR from the practices of 2 ophthalmologists, of whom 11 occurred in women with body mass index ≥ 30, were reviewed. Methods Daily dosing based on real and ideal weight was calculated. Main Outcome Measure Number (percentage) with safe dosing by real weight guidelines but unsafe dosing by ideal weight guidelines. Results In 4 cases (36%), daily dosing was > 5 mg/kg real weight and > 6.5 mg/kg ideal weight. In 4 cases (36%), daily dosing was ≤ 5 mg/kg real weight and ≤ 6.5 mg/kg ideal weight. In 3 cases (27%), daily dosing was ≤ 5 mg/kg real weight and > 6.5 mg/kg ideal weight. No case had daily dosing > 5 mg/kg real weight and ≤ 6.5 mg/kg ideal weight. Conclusions Twenty-seven percent of cases of hydroxychloroquine retinopathy in obese women had ostensibly safe dosing based on AAO 2016 guidelines. Overdosing of obese women by AAO 2016 guidelines is not rare. Daily dosing based on the older 6.5 mg/kg ideal weight threshold is safer in women with BMI ≥ 30.