Hydroxychloroquine in patients with systemic lupus erythematosus with end-stage renal disease

Objectives To determine dosing patterns and examine predictors of filled hydroxychloroquine (HCQ) prescriptions in patients with systemic lupus erythematosus (SLE) with end-stage renal disease (ESRD). Methods This was a retrospective cohort study of patients with SLE in the US Renal Data System (USRDS) database in fiscal year 2011. All patients were Medicare Part D beneficiaries. Patients with a diagnosis of SLE were identified by the International Classification of Diseases, 9th revision code 710. The prevalence, dosing, and predictors of filled HCQ prescriptions (demographic factors, dialysis type, and provider subspecialty) were determined. Results There were 10,276 patients with SLE identified; 2048 (19.9%) had a prescription for HCQ filled. The mean daily dose of HCQ was 321 mg (range 58-2000 mg). The most common daily doses were 200 (n=768, 37.5%) and 400 mg (n=1161, 56.7%). In multivariable logistic regression analysis, significant predictors of filled HCQ prescriptions included black/African-American race (OR 1.34, 95% CI (1.17 to 1.46)), hemodialysis (1.50, 95% CI (1.29 to 1.74)), and care from a rheumatologist (5.06, 95% CI (4.56 to 5.62)). Negative predictors of filled HCQ prescriptions included male gender (OR 0.72, 95% CI (0.63 to 0.83)) and those aged 45 years or older (compared to 20 years old and younger, aged 45-64 years, OR 0.66, 95% CI (0.54 to 0.79); aged 65-74 years, OR 0.58, 95% CI (0.44 to 0.76); aged 75 years and older, OR 0.56, 95% CI (0.39 to 0.82)). Conclusions In patients with SLE with ESRD, the dosing strategies for HCQ with regard to potential toxicity and disparities in prescribing patterns need further study.