Experienced donors, adverse events, and retention

I t is well established that even a mild vasovagal reaction has a negative impact on donor retention. Given the importance of retaining donors, significant efforts have been made to reduce the incidence of these adverse events (AEs). This has led to a number of interventions being introduced—both physiological and psychological. These interventions have primarily been focused on “high-risk” groups, such as the young and newly recruited, and there is evidence that both physiological and psychological interventions are efficacious. Recent evaluations suggest that there are at least four effective strategies for reducing vasovagal reactions: excluding low-estimated-blood-volume (EBV) individuals from making a full donation, refined predonation education, predonation water ingestion, and engaging in (elements of) applied muscle tension (AMT). By reducing vasovagal reactions donor retention can be improved, for novice donors at least. Retaining donors is especially important because these donors are safer and more cost-effective than newly recruited donors. As a cohort they are familiar with the script of donating and are, perhaps primarily through self-selection, statistically less likely to experience AEs. However, reactions among retained donors still occur and their experience as donors does not keep them from being deterred. Importantly, we know little about what type of AEs deter, who is deterred, and what can be done to retain these experienced donors. Further, it is unclear whether the strategies developed for the young and novice donor are viable or relevant for the more experienced donor. The article by Veldhuizen and colleagues in this issue of TRANSFUSION addresses the issue of what deters and who is deterred and provides some preliminary answers as to what can be done to retain experienced donors. Their study draws on data from an experienced sample of whole blood donors (mean, 26.4 prior donations) from the Donor InSight study. Veldhuizen and colleagues examine the relationship between recall of an AE (vasovagal, needle, or other reaction), the Theory of Planned Behavior (TPB) and the risk of stopping donating in the next 2 years. Their analysis shows that needle and vasovagal reactions deter donors from donating in the future, with vasovagal reactions a stronger deterrent than needle reactions. Further, the magnitude of the relationship between vasovagal reactions and stopping is stronger for men than for women. Interestingly, the TPB variables are found to play a key role in explaining the relationship between AEs and stopping—with self-efficacy (a person’s belief in his or her competence or successful performance of a behavior producing the desired outcome) playing a central role. Higher self-efficacy and more positive attitudes were associated with a reduction in the odds of future stopping. Recalling an AE was negatively associated with affective attitudes and self-efficacy, particularly for men. Further, the TPB variables partly explained the relationship between AEs and the risk of no longer donating. As Veldhuizen and coworkers did not test a causal relationship, the direction of the relationship between AEs, self-efficacy, and affective attitudes is unclear. However, despite this, the findings in this and other studies suggest a number of considerations in developing practical strategies to facilitate the retention of the experienced donor in the context of AEs.