Use and prescribing patterns for erythropoiesis-stimulating agents in inpatient and outpatient hospital settings

Abstract

Erythropoiesis-stimulating agent (ESA) use in the outpatient and inpatient settings through pharmacist-conducted, hospital-based chart audits is examined and discussed. Data from four hospital chart audits conducted in 250 hospitals between October 2005 and July 2006 were pooled for analyses. Eligible hospitals were categorized by ESA sales volume, with approximately equal numbers randomly selected from each decile. The last five inpatients and outpatients within each specified month receiving either darbepoetin alfa or epoetin alfa were evaluated. Study variables by setting included ESA use, prescriber specialty, and dosage regimen. The most common hospital locations of ESA administration were a cancer center in the outpatient setting (49%) and general medicine (57%) in the inpatient setting. ESA prescribers were most commonly hematologists and oncologists in the outpatient setting, and nephrologists were the most common prescribers in the inpatient setting. In the outpatient analysis, 2155 patients were prescribed darbepoetin alfa and 3106 were prescribed epoetin alfa. The predominant administration frequencies were every two weeks and once weekly for darbepoetin alfa, and once weekly for epoetin alfa. In the inpatient analysis, 1633 patients were prescribed darbepoetin alfa and 3231 were prescribed epoetin alfa. The predominant administration frequencies were once weekly for darbepoetin alfa and once weekly and three times weekly for epoetin alfa. Common uses for both ESAs were chemotherapy-induced anemia (outpatient setting) and anemia of end-stage renal disease with chronic dialysis (inpatient setting). There was considerable variability in ESA dosages and administration frequencies in both settings within all patient groups when analyzed by specified use. ESA use differed between outpatient and inpatient settings in indication, frequency of administration, and specialty of the prescriber.