OBJECTIVES: Anemia is a treatable and often preventable complication of CKD, but is often under-diagnosed and under-treated. This analysis evaluated the direct medical and indirect work productivity (disability and sick leave) costs before and after the diagnosis of anemia in pre-dialysis CKD patients. METHODS: Anonymous health and disability claims from 31 U.S. employers between January 1998 and January 2006 from ~5 million individuals were used to identify 3449 pre-dialysis CKD patients <65 years of age with ³2 anemia diagnosis claims. The study period was defined as the time from the first CKD claim until the earliest of disenrollment, initiation of dialysis, organ transplantation, or study end. Average per member per month (PMPM) costs were computed before and after the month when anemia was first diagnosed. All costs were calculated from employers' perspectives. RESULTS: Average direct and indirect PMPM costs were respectively $3293 and $501 three months prior to the first anemia diagnosis, $7445 and $838 at the time of diagnosis, and $1794 and $365 twelve months after diagnosis. Increases in inpatient costs were the largest driver for the cost changes over time. Direct and indirect PMPM costs increased more than two-fold in the three months prior to the first anemia diagnosis, leading to a cost peak at the time of diagnosis, and gradually decreased over time to reach cost levels similar to those observed twelve months before diagnosis. CONCLUSION: Direct and indirect costs occurring as early as three months before the formal diagnosis of anemia in pre-dialysis CKD patients could be associated with prodromes of anemia or late diagnosis. These costs peaked at time of diagnosis. Declining costs after diagnosis could suggest benefits of diagnosis and/or treatment of anemia. Further studies are needed to evaluate whether earlier diagnosis and treatment of anemia could reduce or prevent cost escalations in pre-dialysis CKD patients.