Meta-analysis of controlled clinical trials studying the efficacy of rHuEPO in reducing blood transfusions in the anemia of prematurity

BACKGROUND: Recombinant human EPO (rHuEPO) has not gained broad acceptance in the treatment of the anemia of prematurity, because its efficacy in dimi nishing RBC transfusions is questionable. Meta-analysis was used to investi gate the extent and reasons for variation in the results of published clini cal trials. STUDY DESIGN AND METHODS: Prospective controlled trials published from 1990 through 1999 were retrieved; 21 met the criteria for meta-analysis. Calcul ated across these studies were the summary OR of RBC transfusion in treated neonates as compared with controls and the summary mean difference between controls and treated neonates in the volume of RBCs transfused and the num ber of RBC transfusions per infant. Twelve study descriptors were examined as possible reasons for the variation in results. RESULTS: Results of 21 eligible studies varied widely (p<0.001 for the Q te st statistic), and this variation persisted in most analyses when studies w ere stratified by individual study descriptors. When the difference in volu me of RBCs transfused was the outcome measure, variation was modest across the four studies with highly desired characteristics (i.e., high blindness and design quality scores, "conservative" transfusion criteria, and the maj ority of neonates weighing <1 kg at birth), and treatment with rHuEPO reduc ed RBC transfusions by an average of 11.0 mt per kg (p<0.001). CONCLUSION: Benefit from rHuEPO is detected across high-quality studies usi ng conservative RBC transfusion criteria. However, there is extreme variati on overall in the findings of available trials, and-until this variation is accounted for-it is premature to recommend rHuEPO as standard treatment fo r the anemia of prematurity.