We found conflicting evidence for erythropoiesis-stimulating agents to increase quality of life and hemoglobin level by treating anemia in patients with rheumatoid arthritis. However, this conclusion is based on randomized controlled trials with a high risk of bias, and relies on trials assessing human recombinant erythropoietin (EPO). The safety profile of EPO is unclear. Future trials assessing erythropoiesis-stimulating agents for anemia in rheumatoid arthritis should be conducted by independent researchers and reported according to the CONSORT statements. Trials should be based on Outcome Measures in Rheumatoid Arthritis Clinical Trials (OMERACT) and The Patient-Centered Outcomes Research Institute (PCORI) approaches for combining both clinician and patient perspectives.
Availability of iron and degree of inflammation modifies the response to recombinant human erythropoietin when treating anemia of chronic disease in patients with rheumatoid arthritis.
Forty-six patients with rheumatoid arthritis (RA) and documented anemia of chronic disease (Hb < 100/110 g/l) were randomized to receive either human recombinant erythropoietin (r-HuEPO, n = 36, 300 U/kg body weight) or placebo (n = 10) for 12 weeks in a multicenter study. An adequate response was defined as elevation of Hb > or = 120 g/l. Relevant clinical and laboratory assessments were made to evaluate efficacy and secure safety. A significant elevation in Hb from week 10 onwards was noted in twenty-six patients (five drop-outs) out of nine patients receiving placebo (one drop-out) (12 +/- 1.2 g/l vs 4 +/- 0.5 g/l; Hb elevation from 95 g/l to 107 g/l vs 93 g/l to 97 g/l, P < 0.05). Only 14.6%, however, were considered responders according to preset criteria. In the responders a lower initial CRP, a significant reduction in ESR but not in CRP was seen compared to the remaining r-HuEPO group. A significant elevation of energy level was noted in the r-HuEPO group; otherwise, no differences in clinical variables were seen. No serious adverse effects were noted. When analyzing patients receiving oral iron in combination with r-HuEPO and adding five additional, openly selected patients receiving both adequate iron supplementation and r-HuEPO, there was a significant weekly elevation of Hb from week 8 onwards in favor of combination therapy over the ones only receiving r-HuEPO (18 +/- 1.1 g/l vs 7 +/- 1.1 g/l, P < 0.05). The initial six responders had now reached ten of whom seven belonged to the combination therapy group. Response to r-HuEPO in RA patients appears to be dependent on availability of iron and on the degree of inflammation. If r-HuEPO treatment is considered, iron deficiency should always be corrected and strenuous efforts should have been made to control the disease itself.