Secular trends in recombinant erythropoietin therapy among the US hemodialysis population: 1990-1996

Background. Chronic anemia is a major cause of morbidity among the end-stage renal disease (ESRD) population. Recombinant erythropoietin (rHuEPO) has been recognized as a major advance in the treatment of anemia among the ESRD population. This study examines the secular trends in the use of and response to rHuEPO therapy among severely, moderately and mildly anemic hemodialysis patients. Methods. We designed a cohort analytic study using seven years of claims data. The study population comprised all facility-based adult hemodialysis patients receiving rHuEPO therapy, who were initially reimbursed by Medicare in each of the first quarter of the calendar years 1990 through 1996 (N = 64,957). Results. Between 1990 and 1996, the mean rHuEPO dose increased by 139% for the patient cohorts with a first observed hematocrit <0.25, 122% for the 0.25 to 0.29 cohorts, and 107% for the greater than or equal to 0.30 cohorts, and produced a 0.02 to 0.03 increase in achieved hematocrit (A-Hct) over this time. Dosing of rHuEPO did not appear to be influenced by patient or provider characteristics, although African-Americans, the elderly, non-diabetics and persons receiving dialysis in a non-profit facility had a larger percent change in hematocrit compared to their counterparts (P < 0.001). Conclusions. The results of the clinical use of rHuEPO seven years after FDA approval found in the general ESRD hemodialysis population have not equaled the results obtained in the initial clinical trials. Overall, our findings suggest that substantial increases in rHuEPO dose provided to anemic patients have resulted in only modest increases in hematocrit in the seven years since rHuEPO's introduction. Resistance to rHuEPO, prior rHuEPO treatment, inadequate use of supplemental iron, and policy and financial incentives may explain this finding.