Clinical study of serum erythropoietin in anemia of rheumatoid arthritis

Objective To investigate the role of EPO in the pathogenesis of anemia of RA, and define the indication for of rhuEPO treatment. Methods By assessing the serum EPO(s EPO)level in 40 anemic RA patients; and analyzing the relation between s EPO and the Hb level. Results s EPO levels in anemia of RA(52.0,11.2～ 216.0 U/L) were significantly higher than those of normal (4.8,3.3～46.9 U/L) and non anemic rheumatoid patients (7.2, 0.6～20.7 U/L), but lower than those of IDA patients (145.6, 2.6～236.6 U/L). There was a significant linear correlation between Hb and logEPO in these cases and in the control group. There had been no difference in regression slope and linear correlation ( P 0.05), but y intercept of RA with iron deficiency was higher than that in RA without iron deficiency but lower than that by IDA ( P 0.05). Observed/Predicted (logEPO) ratio (O/P ratio) was found at 95% confidence range of O/P ratio of IDA (0.82～1.19). Conclusion s EPO level is relatively deficient in anemia of RA. The level of s EPO in RA varies greatly, hence when using and evaluating the effect of rhuEPO in anemia of RA, s EPO level must be measured and O/P ratio (to equally anemic individuals of IDA) calculated. In these anemic RA patients with iron deficiency, iron preparation should be given first and not rhuEPO.(Shanghai Med J, 2000,23∶267 269)