The iron status of South African blood donors: balancing donor safety and blood demand

Prevalence of Iron Deficiency, Anemia, and Associated Factors in a Blood Donor Population in Brazzaville, Congo

Introduction

Blood donation is not without risk to the donor. It results in a substantial loss of iron and decreased hemoglobin. In our country, no predonation assessment is carried out and the selection of blood donors is only clinical.

Objectives

To determine the prevalence of iron deficiency, anemia, and iron deficiency anemia and to identify the factors associated with anemia and iron status in a blood donor population at the National Center for Blood Transfusion (NCBT). Methodology. A prospective study is carried out that consists of 120 blood donors in three NCBT branches in the capital from June to November 2021. The donors were divided into 3 groups: first time donors (FTDs), occasional donors (ODs) who have already made between 1 and 3 previous donations, and regular donors (RDs) with at least 4 previous donations. Iron deficiency was defined by a serum ferritin value of less than 30 ng/mL in men and 20 ng/mL in women. Anemia was defined by Hb levels below 13 g/dL in men and 12 g/dL in women. Iron deficiency anemia was defined by association of anemia and iron deficiency. The chi-square test was used for the comparison of the proportions. The odds ratio with the 95% confidence interval was calculated to assess the association between two variables. The p value of the probability was considered significant for a value < 0.05.

Results

Mean serum ferritin and hemoglobin values were lower in RD in both sexes. The prevalence of iron deficiency, anemia, and iron deficiency anemia were 16.66%, 31.66%, and 10.83%, respectively. The factors associated with the three abnormalities were female sex, donor type, including RD, and number of previous donations.

Conclusion

Iron deficiency, anemia, and iron deficiency anemia are common among blood donors in Brazzaville. Anemia affects almost a third of blood donors and is not always linked to iron deficiency. Safety of donors should be improved by systematic measurement of ferritinemia and hemoglobin levels before allowing donations for appropriate management in the event of abnormalities.

Iron status of blood donors

PURPOSE OF REVIEW

This review examines recent research on the prevalence and importance of iron deficiency in blood donors, and on efforts to mitigate it.

RECENT FINDINGS

Premenopausal females, teenagers, and high-frequency donors are at the highest risk for donation-induced iron deficiency, in both high-resource and low-resource settings. The physiology relating iron stores to hemoglobin levels and low hemoglobin deferral is well elucidated in blood donor populations, yet the clinical effects attributable to iron loss in the absence of anemia are challenging to identify. Expanded adoption of ferritin testing is improving donor management but may cause decreases in the blood supply from temporary donor loss. The potential for personalized donor management is emerging with development of computational models that predict individual interdonation intervals that aim to optimize blood collected from each donor while minimizing low hemoglobin deferrals.

SUMMARY

Measures to reduce iron deficiency are available that can be deployed on a standardized or, increasingly, personalized basis. Blood centers, regulators, and donors should continue to evaluate different tactics for addressing this problem, to obtain a balanced approach that is optimal for maintaining adequate collections while safeguarding donor health.

Donor Deferral Due to Low Hemoglobin-An Updated Systematic Review

Blood donors attending a donation session may be deferred from donating blood due to a failure to meet low hemoglobin (Hb) thresholds. This costs the blood donor service and donors valuable time and resources. In addition, donors who are deferred may have more symptoms, and as a direct and/or indirect effect of their experience, return rates of donors deferred for low Hb are reduced, even in repeat donors. It is therefore vital that low Hb deferral (LHD) is minimized. The aim of this updated systematic review is to expand the evidence base for factors which affect a donor's risk of deferral due to low Hb. Studies were identified by searching MEDLINE, Embase, The Cochrane Library, and the WHO International Clinical Trials Registry to March 2019. Demographic data, donor history, hematological/biological factors, and the primary outcome of deferral due to low Hb were extracted. Our primary outcome was deferral due to low Hb. Analyses were descriptive and quantitative; pooled odds ratios (ORs) and 95% confidence intervals (CIs) were obtained by meta-analysis using random-effects models. A total of 116 studies met the inclusion criteria. Meta-analysis showed a significantly greater risk of LHD in females compared with males in studies applying universal Hb thresholds for males and females (OR 14.62 95% CI 12.43-17.19) and in those which used sex-specific thresholds (OR 5.73, 95% CI 4.36-7.53). Higher rates of LHD were also associated with increasing age in men, low body weight, shorter interdonation interval, donors of Hispanic or African descent, higher ambient temperature, donors with low ferritin levels, and donation in a fixed donor center. There was conflicting evidence on the effect of new and repeat donor status, and blood group. This work has strengthened the evidence of the previous review in identifying factors that should be considered in studies of donor deferral and highlighting areas in need of further study, including ABO and Rh blood groups, previous platelet donation, diet, smoking, time of day, and genetic data. These factors may lead to individually tailored donation criteria for safe and efficient donation in the future.