Search

Background and Objectives: Regular whole blood donations are associated with an increased risk of iron deficiency. Iron supplementation is an effective strategy to prevent donation‐induced iron deficiency. However, research on donor perceptions towards such a policy is limited. Therefore, we aim to evaluate donors' knowledge on donation‐induced iron depletion and their perceptions regarding iron supplementation as a blood service policy. Materials and Methods: Three thousand Dutch whole blood donors were invited to complete a survey assessing their knowledge of donation‐induced iron depletion and attitudes and perceptions towards iron supplementation as a policy. Linear regression modelling was used to evaluate associations between explanatory variables and perceptions. Results: In total, 1093 (77.1%) donors were included in the analysis. Donors had poor knowledge of current iron management policies, but a better understanding of iron metabolism and supplementation. Iron supplementation as a policy was perceived mainly positive by donors, and the majority were willing to use iron supplements if provided. Iron supplementation was not perceived as invasive or negatively affecting donors' motivation to continue donating. Additional iron monitoring, information and donor physician involvement were regarded as important conditions for implementation. Male sex, trust in the blood service, prior experience with iron supplements and openness towards dietary supplements were strongly positively associated with willingness to use iron supplementation. Conclusion: Donors' knowledge regarding donation‐induced iron depletion is limited, but not associated with their perceptions regarding iron supplementation. Donors do not consider iron supplementation as invasive, deterring or demotivating, and a majority are willing to take supplements if offered. [ABSTRACT FROM AUTHOR]

Introduction: Serological surveillance is useful for assessing SARS-CoV-2 immunity in populations. To effectively study the presence and persistence of antibodies, it is necessary to distinguish between persons with past infection, and persons who only received vaccination. Knowledge of the duration of antibody persistence is essential for correct interpretation of surveillance results. Methods: Starting in April 2020, waning of SARS-CoV-2 antibodies was studied in a longitudinal cohort study of 495 SARS-CoV-2 antibody-positive Dutch blood donors, not pre-selected by PCR testing or disease severity. Additionally, in May 2021, a sample of donors representative for the Dutch population was tested for antibodies against the SARS-CoV-2 spike (S) protein, using the Wantai Ab ELISA and the Elecsys® Anti-SARS-CoV-2 S assay; and for antibodies against the nucleocapsid protein, which indicate past infection, using the Elecsys® Anti-SARS-CoV-2 assay. Results: The anti-S response in donors that were infected in April or May 2020 remained positive in 100% of donors in the Elecsys® Anti-SARS-CoV-2 S assay one year after infection, after which follow up of waning was no longer possible because of large scale vaccination. The anti-nucleocapsid response results were still positive in approximately 80% of donors two years after infection. In May 2021, 51% of the donors showed anti-S reactivity and 16.8% tested positive for anti-nucleocapsid antibodies. Conclusion: Infection with SARS-CoV-2 resulted in spike and nucleocapsid antibody levels still detectable in the majority of donors 1–2 years after infection. In May 2021, 51% of donors were vaccinated and 16.8% had had an infection. Thus, both Elecsys® SARS-CoV-2 antibody assays can be used to reliably assess the vaccination and infection status of individuals. [ABSTRACT FROM AUTHOR]

Background and Objectives: Personalized donation strategies based on haemoglobin (Hb) prediction models may reduce Hb deferrals and hence costs of donation, meanwhile improving commitment of donors. We previously found that prediction models perform better in validation data with a high Hb deferral rate. We therefore investigate how Hb deferral prediction models perform when exchanged with other blood establishments. Materials and Methods: Donation data from the past 5 years from random samples of 10,000 donors from Australia, Belgium, Finland, the Netherlands and South Africa were used to fit random forest models for Hb deferral prediction. Trained models were exchanged between blood establishments. Model performance was evaluated using the area under the precision–recall curve (AUPR). Variable importance was assessed using SHapley Additive exPlanations (SHAP) values. Results: Across the validation datasets and exchanged models, the AUPR ranged from 0.05 to 0.43. Exchanged models performed similarly within validation datasets, irrespective of the origin of the training data. Apart from subtle differences, the importance of most predictor variables was similar in all trained models. Conclusion: Our results suggest that Hb deferral prediction models trained in different blood establishments perform similarly within different validation datasets, regardless of the deferral rate of their training data. Models learn similar associations in different blood establishments. [ABSTRACT FROM AUTHOR]

Background and Objectives: In the Netherlands, as of April 2018, the upper age limit for blood donation has been raised from 69 to 79 years, providing an opportunity to study older donors' perspectives regarding donating at older age. This study aims to explore whether older donors agree with the increase of the age limit, if they feel obliged to continue donating, to identify their motivators and barriers for donating blood and describe donation‐related experiences and complications. Materials and Methods: An online survey was distributed among Dutch blood donors aged 68–73 years. The survey contained questions regarding the increase of the upper age limit, motivations and barriers for donating, donation‐related experiences and obligatory feelings to continue donating. Results: Six hundred sixty donors (55%) were included in the analyses, including 38 stopped donors. Most donors (92%) agreed with the increase of the upper age limit. Approximately 63% of participating donors felt obliged to continue donating, especially women with high education. Donors indicated they felt healthy enough to keep donating (95%), and 72% thought it is good for their health to keep donating. Few donors reported that they found it hard to keep donating (5%) or indicated that they did not feel healthy enough to donate or thought it was not safe for them anymore (3.4%). Conclusion: Most of the older donors agree with the increase of the upper age limit for blood donation, report only few and minor donation‐related experiences or complications and are highly motivated to continue their donor career at an older age. [ABSTRACT FROM AUTHOR]

BACKGROUND: Overweight and obesity impose a considerable individual and social burden, and the urban environments might encompass factors that contribute to obesity. Nevertheless, there is a scarcity of research that takes into account the simultaneous interaction of multiple environmental factors. OBJECTIVES: Our objective was to perform an exposome-wide association study of body mass index (BMI) in a multicohort setting of 15 studies. METHODS: Studies were affiliated with the Dutch Geoscience and Health Cohort Consortium (GECCO), had different population sizes (688–141,825), and covered the entire Netherlands. Ten studies contained general population samples, others focused on specific populations including people with diabetes or impaired hearing. BMI was calculated from self-reported or measured height and weight. Associations with 69 residential neighborhood environmental factors (air pollution, noise, temperature, neighborhood socioeconomic and demographic factors, food environment, drivability, and walkability) were explored. Random forest (RF) regression addressed potential nonlinear and nonadditive associations. In the absence of formal methods for multimodel inference for RF, a rank aggregation-based meta-analytic strategy was used to summarize the results across the studies. RESULTS: Six exposures were associated with BMI: five indicating neighborhood economic or social environments (average home values, percentage of high-income residents, average income, livability score, share of single residents) and one indicating the physical activity environment (walkability in 5-km buffer area). Living in high-income neighborhoods and neighborhoods with higher livability scores was associated with lower BMI. Nonlinear associations were observed with neighborhood home values in all studies. Lower neighborhood home values were associated with higher BMI scores but only for values up to e300,000. The directions of associations were less consistent for walkability and share of single residents. DISCUSSION: Rank aggregation made it possible to flexibly combine the results from various studies, although between-study heterogeneity could not be estimated quantitatively based on RF models. Neighborhood social, economic, and physical environments had the strongest associations with BMI. [ABSTRACT FROM AUTHOR]

Epidemiological studies have linked adult height with breast cancer risk in women. However, the magnitude of the association, particularly by subtypes of breast cancer, has not been established. Furthermore, the mechanisms of the association remain unclear. We performed a meta-analysis to investigate associations between height and breast cancer risk using data from 159 prospective cohorts totaling 5216302 women, including 113178 events. In a consortium with individual-level data from 46325 case patients and 42482 control patients, we conducted a Mendelian randomization analysis using a genetic score that comprised 168 height-associated variants as an instrument. This association was further evaluated in a second consortium using summary statistics data from 16003 case patients and 41335 control patients. The pooled relative risk of breast cancer was 1.17 (95% confidence interval [CI] = 1.15 to 1.19) per 10cm increase in height in the meta-analysis of prospective studies. In Mendelian randomization analysis, the odds ratio of breast cancer per 10cm increase in genetically predicted height was 1.22 (95% CI = 1.13 to 1.32) in the first consortium and 1.21 (95% CI = 1.05 to 1.39) in the second consortium. The association was found in both premenopausal and postmenopausal women but restricted to hormone receptor-positive breast cancer. Analyses of height-associated variants identified eight new loci associated with breast cancer risk after adjusting for multiple comparisons, including three loci at 1q21.2, DNAJC27, and CCDC91 at genome-wide significance level P < 5×10(-8). Our study provides strong evidence that adult height is a risk factor for breast cancer in women and certain genetic factors and biological pathways affecting adult height have an important role in the etiology of breast cancer.

Background and Objectives: As part of a large‐scale project to safely increase plasma collection in Europe, the current scoping review identifies the existing evidence (gaps) on adverse events (AEs) and other health effects in plasmapheresis donors, as well as factors that may be associated with such events/effects. Materials and Methods: We searched six databases and three registries. Study characteristics (publication type, language, study design, population, outcomes, associated factors, time of assessment, duration of follow‐up, number and frequency of donations, convalescent plasma [y/n], setting and location) were synthesized narratively and in an interactive evidence gap map (EGM). Results: Ninety‐four research articles and five registrations were identified. Around 90% were observational studies (57 controlled and 33 uncontrolled), and most of them were performed in Europe (55%) or the United States (20%). Factors studied in association with donor health included donor characteristics (e.g., sex, age) (n = 27), cumulative number of donations (n = 21), donation frequency (n = 11), plasma collection device or programme (n = 11), donor status (first time vs. repeat) (n = 10), donation volume per session (n = 8), time in donation programme (n = 3), preventive measures (n = 2) or other (n = 9). Conclusion: The current scoping review provides an accessible tool for researchers and policymakers to identify the available evidence (gaps) concerning plasmapheresis donation safety. Controlled prospective studies with long‐term donor follow‐up are scarce. Furthermore, additional experimental studies comparing the health effects of different donation frequencies are required to inform a safe upper limit for donation frequency. [ABSTRACT FROM AUTHOR]

Background and Objectives: Iron supplementation is an effective strategy to mitigate donation‐induced iron deficiency in blood donors. However, evidence on the perception of individuals involved in blood donation on iron supplementation as a blood service policy is lacking. This study aimed to evaluate the knowledge and perception of whole blood donors (donors), blood collection staff (collection staff) and donor physicians (physicians) regarding donation‐induced iron loss and iron supplementation. Materials and Methods: Online focus group discussions had four to six participants and followed a structured questioning approach. All participants had to be fluent in Dutch to participate, and donors had donated at least five times. Sixteen donors, eight collection staff members and four physicians participated in this study. Recordings were transcribed, coded and analysed using a grounded theory approach. Results: Awareness of donation‐induced iron loss was limited in donors. Donors and physicians were predominantly positive towards iron supplementation; the primary motivator for donors was to prevent deferral and reduce iron‐deficiency‐related symptoms. Improving donor health was the main argument for physicians to advocate iron supplementation. Staff had a critical view on iron supplementation as a policy, as they perceived it as unethical and possibly ineffective. A knowledge gap might underlie their concerns. Conclusion: Most individuals involved in blood donation are positive towards iron supplementation as a blood service policy. If implemented, guidance and monitoring is desired and adequate education of all stakeholders is required. [ABSTRACT FROM AUTHOR]

The article discusses the growing utilization of Plasma-Derived Medicinal Products (PDMPs) and the importance of ensuring the safety of plasma donors. It critiques two studies that concluded that repeated plasmapheresis (plasma donation) is safe for donors, pointing out methodological shortcomings and selection biases in the studies. The authors argue that more robust evidence, such as randomized controlled trials (RCTs) and real-world data analysis, is needed to determine the long-term impact of repeated plasmapheresis on donor health. They emphasize the need for trustworthy evidence syntheses and transparent criteria for evaluating the quality of evidence. Until more conclusive evidence is available, blood establishments will continue to prioritize donor safety. [Extracted from the article]

Background and Objectives: Serum ferritin levels are increasingly being used to assess iron stores. Considerable variation in ferritin levels within and between individuals has been observed, but our current understanding of factors that explain this variation is far from complete. We aim to combine multiple potential determinants in an integrative model, and investigate their relative importance and potential interactions. Methods: We use ferritin measurements collected by Sanquin Blood Bank on both prospective (N = 59 596) and active blood donors (N = 78 318) to fit a structural equation model with three latent constructs (individual characteristics, donation history, and environmental factors). Parameters were estimated separately by sex and donor status. Results: The model explained 25% of ferritin variance in prospective donors, and 40% in active donors. Individual characteristics and donation history were the most important determinants of ferritin levels in active donors. The association between environmental factors and ferritin was smaller but still substantial; higher exposure to air pollution was associated with higher ferritin levels, and this association was considerably stronger for active blood donors than for prospective donors. Discussion: In active donors, individual characteristics explain 20% (17%) of ferritin variation, donation history explains 14% (25%) and environmental factors explain 5% (4%) for women (men). Our model presents known ferritin determinants in a broader perspective, allowing for comparison with other determinants as well as between new and active donors, or between men and women. [ABSTRACT FROM AUTHOR]

Background and Objectives: To protect transfusion recipients from transfusion‐transmissible infections, blood donors are deferred from donating after recent tattooing or piercing. To explore to what extent and how this deferral impacts donor availability, we performed an international study to investigate how many donors were deferred for a recent tattoo or piercing and how many of these donors returned to donate. Materials and Methods: We surveyed blood centre members of the Biomedical Excellence for Safer Transfusion (BEST) Collaborative and the European Blood Alliance Donor Studies Working Group on their numbers of donations, tattoo and piercing deferrals, and return rates in the year 2017. Results: Eight blood centres participated. Overall, deferral rates were lower for repeat donors compared to new donors. Repeat donors were more likely to return than new donors. Women and young donors were more often deferred than male and older donors. Men were more demotivated by tattoo or piercing deferral, resulting in lower return rates compared to women. Return rates differed greatly between blood centres. Conclusion: Tattoo and piercing deferrals lead to missed donations and result in lower return rates. However, the numbers vary largely internationally, probably due to cultural and policy differences. Shortening deferral periods after tattooing or piercing may reduce the impact on donor availability, which should be investigated in single‐centre studies. [ABSTRACT FROM AUTHOR]

Background and Objectives: Donor eligibility questions and criteria for medical conditions vary between blood centres, suggesting that they are based more on local regulations or experience, rather than on published data, which are limited. As the donor population ages, medical conditions become more common. We assessed donor health assessment criteria at blood centre members of the Biomedical Excellence for Safer Transfusion (BEST) Collaborative. Our aim was to compare eligibility criteria and determine their underlying basis. Materials and Methods: A REDCap survey was sent to blood centre participants, based on medical conditions of greatest interest suggested by the Donor Studies Team of the BEST Collaborative. Participants were asked about current donor health assessment questions, deferral criteria and the basis for their deferral policy (donor risk, recipient risk or both) for 20 medical conditions. Results: Complete responses were received from 26 blood donor centres (24 separate responses) representing a combination of hospital‐based centres, large regional centres and community/national blood centres in 14 different countries. Most centres specifically ask about heart and lung conditions, whereas fewer than half inquire about kidney, gastrointestinal or neurological conditions. North American blood centres tended to be less restrictive, while regulatory restrictions are more prevalent in Europe. Most participants felt that the criteria were based on regulatory requirements or experience, rather than on published data. Conclusion: There is considerable variability in criteria by region. Ideally, criteria would be more evidence‐based rather than based on regulatory requirements or experience. Deferral criteria must balance donor and recipient safety and maintain an adequate blood supply. [ABSTRACT FROM AUTHOR]