The influence of obesity on hydroxychloroquine blood levels in lupus nephritis patients

摘要

Introduction In 2016 the American Academy of Ophthalmology(2016-AAO) recommended a maximum daily HCQ use of 5.0?mg/kg real body weight(RBW) taking into consideration minimizing eye toxicity. Retinopathy in systemic lupus erythematosus(SLE) patients was recently associated with obesity and this condition is progressively more common in these patients. However, the impact of obesity in HCQ blood levels remains controversial. Objective To determine if the 2016-AAO recommendation based on RBW with and without maximum daily dose restriction results in adequate and safe blood levels in obese lupus nephritis(LN) patients. Methods A cross-sectional study was performed with 108 LN patients under the prescribed 2016-AAO dose for at least 3?months. LN patients were assessed for demographic characteristics, body mass index(BMI), disease parameters, HCQ dose, concomitant treatment and HCQ blood levels measured by liquid chromatography-tandem mass spectrometry. Obesity was defined as BMI ≥30kg/m~(2). Results Obesity was identified in 35/108(32%) LN patients. The calculation of HCQ daily dosage revealed that obese patients were under a lower prescribed daily dose according to the real body weight (RBW) [4.4(2.9-5.4) vs. 4.9(4-5.5)mg/Kg/day, p?