Background/Case Studies: CVD affects 128 million (48.6%) American adults (2023). Blood donors (BDs) are considered healthy, but statistically, many donors may have underlying CVD. Policies regarding accepting donors with CVD are based largely on concerns for donor safety, specifically the impact of vasovagal reactions (VVR) and associated cardiovascular complications. This study sought to identify specific diagnoses associated with higher rates of LOC.
Study
Design/Methods: We identified allogeneic whole blood (WB) presentations in 2021-2022, correlating self-reported current/past CVD and observed or reported LOC and reaction severity. In BDs with CVD meeting eligibility criteria (no symptoms, new diagnoses/treatment, restrictions in previous 6 months), we classified CVD diagnoses into: coronary artery disease (CAD), arrhythmia/conduction block (AB), structural/congenital disease, murmurs, mixed disease (inflammatory/cardiomyopathy), congestive heart failure (CHF), cerebrovascular disease, peripheral arterial disease, and deep venous thrombosis. We performed multivariate logistic regression analysis (MVA) on factors associated with LOC with CVD categories and variables previously reported to be associated with LOC (Figure A).
Results/Findings: In 1,660,229 allogeneic WB presentations, 34,672 (0.02%) BDs reported CVD, of whom 99.7% met acceptance criteria. No serious adverse events (heart attacks, strokes) or hospitalizations occurred in BD with CVD. The proportion of outside medical care was similar for CVD (0.029%) and non-CVD BDs (0.032%). There were 3,504 LOC events reported, 64 had CVD, 92% (n=59) severity grade 1, and the remaining 8% (n=5) grade 2. LOC reaction severity grade 1 & 2 rates were similar between CVD and non-CVD BDs. Severity grades above 2 were only observed among non-CVD BDs. Overall, LOC rates were not statistically different between non-CVD (0.21%) and CVD (0.18%) BDs. The MVA showed significant increased odds ratio (OR) of LOC (Figure A) in: AB-related conditions (v. no CVD), younger age (v. 25-64), FT/Reengaged (v. Repeat), lower EBV (v. ≥5000 mL) and pulse >90 bpm (v. 65-90 bpm). Expected decreased odds ratio associations with LOC were also noted (Figure A). None of the BDs reporting AB-related CVD had irregular pulse at medical screening. Conclusions: BDs reporting CVD during medical screening represent a small proportion of BDs presenting for WB donation. Most meet medical acceptance criteria. Among BDs reporting various types of CVD, risk is increased only among those with AB-related CVD. None of the reactions were life-threatening and can be mitigated by emphasis on generally accepted intervention strategies. This study supports our current eligibility criteria for BDs with CVD.
Importance of research: Studies have shown that many donors with cardiovascular disease (CVD) can donate safely. This study is unique as it sought to identify specific CVD associated with higher rates of loss of consciousness (LOC) and severe reactions.
