Iron Deficiency Anemia and Chronic Renal Insufficiency In An Oncology Population

Abstract 5152

Anemia in oncology patients is common and may negatively impact cancer treatment outcomes. Iron deficiency is a major contributor to anemia, which can be exacerbated by both underlying conditions and chemotherapeutic agents. Additionally, many oncology patients may have concomitant renal insufficiency or chronic kidney disease (CKD), increasing their susceptibility to iron deficiency. Therefore, recognizing renal insufficiency as well as iron deficiency may improve anemia management in oncology patients.

To determine the proportion of oncology patients with iron deficiency anemia (IDA), potential renal insufficiency and the current utilization of IV iron treatment in these populations, a large electronic medical records database was examined. All patients treated with chemotherapy in a physician services oncology network from January 1, 2008 to August 1, 2010 were selected in order to determine the prevalence of an iron deficiency anemia (IDA) diagnosis (expressed as an ICD-9-CM 280.1-.9), and a diagnosis of CKD (expressed as either from a diagnosis code of CKD (585.1-.6) or estimated GFR <60 mL/min).

Overall, 83,219 patients receiving a chemotherapeutic agent were selected. Of these patients, 36% (30,298) were diagnosed with IDA, 34% of whom were receiving IV iron treatment (9,971/30,298). These patients represented approximately 85% (9971/11,776) of the total IV iron treated population in the dataset.

While only 8% (2,482/30,298) of patients with a diagnosis of IDA also had a diagnosis of CKD. Of the patients that did present with a GFR level, 49% of patients had a GFR level <60 mL/min. However, the true prevalence of CKD in this population was difficult to determine because a significant percentage of patients did not present with a GFR level available in their records.

In this oncology patient population IDA is relatively common, with greater than 30% of patients diagnosed. While only one third of these patients were receiving IV iron treatment in the IDA patient population, it is unknown whether patients are not being treated for their iron deficiency or are being managed on oral iron therapy alone. Given recent controversies around ESA use, guidelines suggest that iron indices should be checked, and IV iron supplementation should be considered in patients receiving ESA therapy. Additionally, only a fraction of patients diagnosed with IDA are also diagnosed with CKD, even though analysis of GFR values suggests that a significant number of patients may have renal insufficiency. These data suggest that identification of patients with renal insufficiency may be suboptimal and that further treatment of IDA in this patient population may be warranted in order to optimize anemia management.