Placebo and nocebo effects in transfusion medicine

Abstract

Background Our own observations suggested that placebo and nocebo effects may occur with transfusions. However these effects seem to have been poorly studied. Objectives To examine published information on, and draw attention to the possibility of, placebo and nocebo effects with transfusion. Methods Focused literature review. Results There is some information on placebo effects with clotting factors and this effect appears modest at best. There is very little published information on this regarding other fresh blood components. Although unknown biologic effects cannot be ruled out, there are hints that placebo effects might operate ‐ especially with red blood cell transfusions. There is practically no information on nocebo effects with transfusions. Conclusions There are ways of surmounting the practical and ethical difficulties involved, and obtaining better information on both types of effects. Individualised, contextualised, informed consenting of transfusion recipients may help to enhance placebo, and reduce nocebo, effects. This may be supportable ethically, and desirable clinically, and financially.

The efficacy and safety of tezepelumab in the treatment of uncontrolled asthma: A systematic review and meta-analysis of randomized controlled trials

“…One possible explanation for this is the "placebo effect," a phenomenon in which negative effects are attributed to the placebo. [26][27][28] On the other hand, the higher prevalence of adverse events in the placebo groups can also be explained by the clinical characteristics of the disease. In heterogeneous and chronic inflammation (such as asthma), respiratory tract involvement is common.…”