OBJECTIVES: Chronic Kidney Disease (CKD) is a significant health care problem in the United States; iron deficiency anemia can greatly impact resource utilization. We compared patient and health characteristics and health care utilization of members with stage 3 CKD with anemia versus without anemia in a regional integrated healthcare system. METHODS: Patients 18 and older were identified with a calculated GFR between 30 and 59 ml/min/1.73m3 (stage 3) using the MDRD equation or ICD-9 diagnosis code of 585.3 between July 1, 2004 and June 30, 2007.  Patients were required to be continuously enrolled for 6 months pre- and 24 months post-index dates.  Anemia patients were identified with ICD-9 codes (280.0-280.9, 285.21, 285.29, or 285.9) or hemoglobin values (<13, male; <12, female). Dialysis patients were excluded. Descriptive and inferential statistics were utilized.   RESULTS: 2,739 patients met inclusion criteria; 24% (n=648) had anemia.  8.4% (n=231) of patients were identified by ICD-9, while 17% (n=113) of anemia patients had the above ICD-9 codes. Mean age was 73.3 and 71.5 years (p<0.001) for with anemia and without anemia groups, respectively. 58% and 27% of anemia patients had comorbid hypertension and diabetes, respectively, versus 50% and 19% in the without anemia group. Per patient visit to nephrology, inpatient, and ED were as follows: 0.52, 4.33, and 0.53 for anemia, 0.19, 1.74, and 0.28 for without anemia (p<0.001).  Average health care costs during the post-index period was 59% higher (p<0.001) for anemia patients versus patients without anemia. 8% of anemia patients progressed to stage 4 versus 4.5% for without anemia patients. 20.1% (n=130) of anemia patients were treated with either an erythropoietin stimulating agent (14.5%) or intravenous iron therapy (5.6%); 3.9% (n=25) were treated with both. CONCLUSIONS: CKD remains under-diagnosed and patients with anemia utilize more resources compared to CKD patients without anemia; however, anemia remains under-treated.