Factors associated with anemia among incident pre-dialysis patients managed within a French care network

Despite guidelines concerning the management of renal anemia, the international literature reports that a large proportion of pre-dialysis patients have hemoglobin values lower than the recommended level. The present study analyzed the evolution of pre-dialysis Hb levels and erythropoietin use over a 4-year period and investigated factors associated with anemia.

A total of 1315 patients initiating dialysis in Lorraine, France, were enrolled since 2001-2004. For each year, anemia, defined by Hb <11 g/dl, and erythropoietin use were investigated in three groups: all patients, patients whose dialysis was planned and patients whose dialysis was unplanned.

At initiation of dialysis, all groups showed increases over time in mean hemoglobin levels, proportion of patients without anemia and with erythropoietin therapy. Among patients whose first dialysis was planned in 2004, 43.8% had anemia and 67.9% had received erythropoietin, compared with 75.4% and 29.4%, respectively, when dialysis was unplanned. Patients receiving unplanned dialysis were more likely to have anemia (odds ratio (OR) = 2.6), as were those with a serum albumin level < 3.5 g/dl (OR = 2.1), body mass index < 30 kg/m2 (OR = 1.9) (all p < 0.001) or glomerular filtration rate < 10 ml/min/1.73 m2 (OR = 1.4, p = 0.04). The year of dialysis initiation was also associated with anemia (p = 0.024).

The proportion ofpatients starting dialysis with anemia might be reduced by earlier nephrology referral leading to erythropoietin administration, planned first dialysis while residual renal function remains, and greater attention to nutritional status.