Monoclonal B-cell lymphocytosis in healthy blood donors: an unexpectedly common finding.

Circulating monoclonal B cells may be detected in healthy adults, a condition called monoclonal B-cell lymphocytosis (MBL). MBL has also been identified in donated blood, but no systematic study of blood donors has been reported. Using sensitive and specific laboratory methods, we detected MBL in 149 (7.1%; 95% confidence interval, 6.0% to 8.3%) of 2098 unique donors ages 45 years or older in a Midwestern US regional blood center between 2010 and 2011. Most of the 149 donors had low-count MBL, including 99 chronic lymphocytic leukemia-like (66.4%), 22 atypical (14.8%), and 19 CD5(-) (12.8%) immunophenotypes. However, 5 donors (3.4%) had B-cell clonal counts above 500 cells per µL, including 3 with 1693 to 2887 cells per µL; the clone accounted for nearly all their circulating B cells. Four donors (2.7%) had 2 distinct MBL clones. Of 51 MBL samples in which immunoglobulin heavy chain (IGH)V-D-J genotypes could be determined, 71% and 29% used IGHV3- and IGHV4-family genes, respectively. Sequencing revealed 82% with somatic hypermutation, whereas 18% had >98% germ-line identity, including 5 with entirely germ-line sequences. In conclusion, MBL prevalence is much higher in blood donors than previously reported, and although uncommon, the presence of high-count MBL warrants further investigations to define the biological fate of the transfused cells in recipients.

Fear of blood draw and total draw time combine to predict vasovagal reactions among whole blood donors.

BACKGROUND: Fear of blood draws is a predictor of vasovagal reaction risk among whole blood donors, and this relationship is particularly evident among less experienced donors. This study examines the combined effect of donor fear and total blood draw time on vasovagal reactions. STUDY DESIGN AND METHODS: After successfully completing the blood donor health screening, 2730 whole blood donors attending high school drives were asked about their fear of having blood drawn. Donor reports of fear versus no fear were combined with total blood draw time to predict phlebotomist ratings of donor vasovagal reactions. RESULTS: Both fear and draw time were significant predictors of vasovagal reactions, with observed reaction rates of 31.2% for fearful donors whose blood draw lasted 10 minutes or more versus 5.0% for nonfearful donors whose draw lasted less than 6 minutes. Binomial regression analyses revealed that fear remained a significant predictor of reaction rates across all blood draw intervals examined (odds ratio, 2.8-4.1; all p < 0.001) and that these effects were maintained after controlling for donor sex, weight, estimated blood volume, pulse rate, and donation status. CONCLUSION: This report shows that both fear and blood draw time increase vasovagal reaction rates, and the two are additive. These findings suggest that fearful donors should be the focus of special attention to reduce their distress before donation as well as careful observation throughout the draw.

Fear of blood draws, vasovagal reactions, and retention among high school donors.

BACKGROUND: We previously demonstrated that fear of having blood drawn is one of the strongest known predictors of vasovagal reactions among high school blood donors. This report examines the combined effects of donor fear and experience of vasovagal reactions on repeat donation attempts among high school blood donors. STUDY DESIGN AND METHODS: Immediately after completing the blood donor health screening, 1715 high school students were asked about their fear of having blood drawn. The donor record was then used to collect information regarding their experience of vasovagal reactions at the time of donation as well as their subsequent donation attempts within the following year. RESULTS: Fear of having blood drawn and the experience of a vasovagal reaction each contributed to donor attrition, with only 33.2% of fearful donors who experienced a vasovagal reaction returning in the following year compared to 56.7% of nonfearful nonreactors. Path analyses demonstrated that fear has an indirect effect (through vasovagal reactions) on repeat donations among first-time donors and both direct and indirect effects on repeat donation attempts among experienced donors. CONCLUSION: Among high school blood donors, fear of having blood drawn has both a direct negative effect on donor retention and an indirect negative effect by increasing the risk of vasovagal reactions. Accordingly, targeted efforts to reduce donor fear may be particularly efficient in promoting long-term donor loyalty among our youngest donors.

How afraid are you of having blood drawn from your arm? A simple fear question predicts vasovagal reactions without causing them among high school donors.

BACKGROUND: We previously demonstrated in a group of mostly experienced blood donors that fear of blood draws was a significant predictor of vasovagal reactions. Importantly, being asked about one's fear immediately before donation did not increase reaction rates. This study further evaluates the relationship between fear and reactions among high school blood donors, who are known to be at a relatively greater risk for vasovagal reactions. STUDY DESIGN AND METHODS: Immediately after completing the blood donor health screening, 17- and 18-year-old high school students were asked about their fear of having blood drawn. Based on a random selection, the fear question was administered in approximately half of the schools, resulting in a final sample of 1715 donors who did and 1692 donors who did not answer the fear question. RESULTS: Fear was a significant predictor of donor reactions and remained a significant independent predictor (along with estimated blood volume and donor sex) in a logistic regression analysis. There was no difference in the proportion of reactions observed between those who did and did not answer the predonation fear question. CONCLUSION: Consistent with previous evidence in older and more experienced blood donors, these findings indicate that assessing fear of blood draws may help to identify those who are most likely to experience vasovagal reactions among young donors without increasing the frequency of such reactions.

Assessment of donor fear enhances prediction of presyncopal symptoms among volunteer blood donors.

BACKGROUND: Fear is an important contributor to the risk of presyncopal reactions to blood donation. However, concern that asking donors about their fears may increase the risk of reactions is a potential impediment to incorporating fear assessment into donor screening. STUDY DESIGN AND METHODS: Before donation, participants responded to a series of questions that either did (n = 488) or did not (n = 494) include questions related to fear of seeing blood drawn. Immediately after donation all participants provided ratings of presyncopal reactions. RESULTS: Among those asked predonation fear questions, fear was most strongly related to presyncopal symptoms when compared against other donor characteristics (e.g., age, number of prior donations, body mass index, estimated blood volume, blood pressure, and pulse). However, Mann-Whitney U tests revealed that being asked about fear before donation was not associated with higher reports of presyncopal reactions for the sample as a whole, nor among novice donors. Further, regression analyses indicated that fear remained a significant predictor of presyncopal reactions in final models that included age and number of prior donations as significant predictors. CONCLUSION: Predonation assessment of fear of blood draws may help to identify donors who are most likely to benefit from brief interventions designed to enhance donor coping, reduce risk of presyncopal reactions, and increase donor retention.