Evidence for impaired erythropoietin response to anaemia in rheumatoid disease.

ABSTRACT

In this study we determined the serum erythropoietin (Epo) levels of 97 anaemic rheumatoid (RD) patients (Hb less than 11 g/dl) of whom 44 had serum ferritin greater than 60 micrograms/l (anaemia of chronic disorders; ACD), 26 had ferritin 20-60 micrograms/l and 27 had ferritin less than 20 micrograms/l. These results were compared with the Epo levels of 36 iron deficient controls (Hb less than 11 g/dl), 33 non-anaemic RD patients and 33 normals. The serum Epo levels of anaemic subjects were significantly higher (P less than 0.05) than those of non-anaemic patients. Despite similar Hb, the Epo results (geometric mean (confidence limits] of the ACD group (38 (32,45) mU/ml) and of RD patients with ferritin of 20-60 micrograms/l (39 (33,46)mU/ml) were significantly lower (P less than 0.05) than those of iron deficient controls (65 (52,80)mU/ml). When the Hb fell to 10 g/dl or less, the serum Epo of 13 RD patients with ferritin less than 20 micrograms/l was 65 (47,89)mU/ml, significantly lower (P less than 0.05) than that of 17 iron deficient controls (104 (78,136)mU/ml). These results justify clinical trials of recombinant human Epo in RD patients with ACD.