Transmission of XXXX by blood transfusion: risk factor or possible biases.

@entity1 @entity16 @entity3605 @entity13895 @entity74
BACKGROUND: The occurrence of transfusion transmissions of variant @entity3605 ( @entity3605 ) cases has reawakened attention to the possible similar risk posed by other forms of @entity3605 . STUDY DESIGN AND METHODS: @entity3605 with a definite or probable diagnosis ( @entity13895 , n = 741; @entity74 , n = 175) and no- @entity3605 @entity1 with definite alternative diagnosis (n = 482) with available blood transfusion history were included in the study. The risk of exposure to blood transfusion occurring more than 10 years before disease onset and for some possible confounding factors was evaluated by calculating crude odds ratios (ORs). Variables with significant ORs in univariate analyses were included in multivariate logistic regression analyses. RESULTS: In the univariate model, blood transfusion occurring more than 10 years before clinical onset is 4.1-fold more frequent in @entity13895 than in other @entity16 . This significance is lost when the 10-year lag time was not considered. Multivariate analyses show that the risk of developing @entity13895 after transfusion increases (OR, 5.05) after adjusting for possible confounding factors. Analysis conducted on @entity1 with @entity74 did not reveal any significant risk factor associated with transfusion. CONCLUSION: This is the first case-control study showing a significant risk of transfusion occurring more than 10 years before clinical onset in @entity13895 @entity1 . It remains questionable whether the significance of these data is biologically plausible or the consequence of biases in the design of the study, but they counterbalance previous epidemiologic negative reports that might have overestimated the assessment of blood safety in @entity13895 .
