Prognostic value of red blood cell parameters and ferritin in predicting deferral due to low hemoglobin in whole blood donors

Impact of a post-donation hemoglobin testing strategy on efficiency and safety of whole blood donation in England: A modeling study

BACKGROUND

Deferrals due to low hemoglobin are time-consuming and costly for blood donors and donation services. Furthermore, accepting donations from those with low hemoglobin could represent a significant safety issue. One approach to reduce them is to use hemoglobin concentration alongside donor characteristics to inform personalized inter-donation intervals.

STUDY DESIGN AND METHODS

We used data from 17,308 donors to inform a discrete event simulation model comparing personalized inter-donation intervals using "post-donation" testing (i.e., estimating current hemoglobin from that measured by a hematology analyzer at last donation) versus the current approach in England (i.e., pre-donation testing with fixed intervals of 12-weeks for men and 16-weeks for women). We reported the impact on total donations, low hemoglobin deferrals, inappropriate bleeds, and blood service costs. Personalized inter-donation intervals were defined using mixed-effects modeling to estimate hemoglobin trajectories and probability of crossing hemoglobin donation thresholds.

RESULTS

The model had generally good internal validation, with predicted events similar to those observed. Over 1 year, a personalized strategy requiring ≥90% probability of being over the hemoglobin threshold, minimized adverse events (low hemoglobin deferrals and inappropriate bleeds) in both sexes and costs in women. Donations per adverse event improved from 3.4 (95% uncertainty interval 2.8, 3.7) under the current strategy to 14.8 (11.6, 19.2) in women, and from 7.1 (6.1, 8.5) to 26.9 (20.8, 42.6) in men. In comparison, a strategy incorporating early returns for those with high certainty of being over the threshold maximized total donations in both men and women, but was less favorable in terms of adverse events, with 8.4 donations per adverse event in women (7.0, 10,1) and 14.8 (12.1, 21.0) in men.

DISCUSSION

Personalized inter-donation intervals using post-donation testing combined with modeling of hemoglobin trajectories can help reduce deferrals, inappropriate bleeds, and costs.

Assessment of iron status in regular blood donors in a tertiary care hospital in Southern India

BACKGROUND

Regular blood donation depletes iron stores. The assertion is that the vulnerable donor population requires a predictive standard operative procedure for early detection of iron store depletion, preventing them from developing iron-deficiency anemia.

AIM

This study aims to study the potential effects of blood donation in the regular donor group using hematological and biochemical estimation of iron status parameters.

STUDY SETTINGS AND DESIGN

This was a prospective cross-sectional study on regular blood donors, defined as those who have donated at least 3 times, the last donation being within the last 12 months and continues to donate at least once a year, at a tertiary care teaching hospital in Southern India.

MATERIALS AND METHODS

The complete blood count (CBC) was performed on the Sysmex coulter, and the red cell indices were calculated. The ferritin and the soluble transferrin receptor (sTfR) assays were performed using Enzyme Immunoassays.

STATISTICAL ANALYSIS USED

The comparison of CBC, serum ferritin, and sTfR assay with donation frequency and time since the last donation was carried out using an independent student's t-test for two groups. The statistical analysis was performed using SPSS for Windows version 20.

RESULTS

A total of 323 regular blood donors (6 were females) were included in the study of which they were categorized into three, 211 donors with less than or equal to 10 donations, 84 those who had donated between 11 and 20 times and 28 who had donated more than 20 times. The red cell indices were reduced and different in the groups but not statistically significant except for mean corpuscular volume. About 15% of the study population had a transferrin level of <15 ng/ml. The Ferritin levels showed a statistically significant negative correlation with the number of donations, the correlation coefficient being -0.27. Logarithmic ratios of sTfR/ferritin also correlated with a coefficient of 0.156 with the number of donations and were statistically significant.

CONCLUSION

Our study found that regular blood donors had low iron stores, as shown by ferritin levels and other iron indicators. Using the current guidelines (hemoglobin >12.5 g/dL) for donation, or the red cell indices alone do not reflect the donor's actual iron status.

Long-Term Course of Haemoglobin and Ferritin Values in High-Frequency Donors of Whole Blood and Double Erythrocyte Apheresis

Background

High-intensity donation is a risk factor for iron deficiency in blood donors. Interdonation intervals for whole blood (WB) donation and double unit red blood cell apheresis (2RBC) vary among countries. We retrospectively evaluated the course of haemoglobin (Hb) and ferritin values in men regularly donating WB 4 times a year or 2RBC twice a year (i.e., maximal frequency) over a period of 48 months.

Methods

Data of male donors with 16 WB or 8 2RBC consecutive donations were analysed. The minimum Hb levels for WB donation and 2RBC apheresis (collection of 360 mL RBC) were 135 and 140 g/L, respectively. There was no lower limit set for ferritin, and no iron was substituted.

Results

We identified 294 WB (mean age 53 years, SD 11) and 151 2RBC donors (mean age 48 years, SD 9) who donated at a mean interval of 97 (SD 18) and 201 days (SD 32), respectively, between January 1, 2008, and December 31, 2013. At baseline, Hb and ferritin values were lower in WB donors compared to 2RBC donors, with a mean Hb of 153 g/L (SD 13) versus 159 g/L (SD 8) and a mean ferritin of 44 μg/L (SD 52) versus 73 μg/L (SD 56; p < 0.001 for both parameters), respectively. Ferritin was below 15 μg/L in 40 WB (14%) and in 4 (3%) 2RBC donors. In WB donors, the mean Hb levels at baseline versus last donation showed no significant difference (153 vs. 152 g/L, p = 0.068), whereas the mean ferritin levels decreased significantly (44 vs. 35 μg/L, p < 0.001). The 2RBC donor group displayed a statistically different decrease in both the mean Hb levels (158 vs. 157 g/L; p < 0.05) and the mean ferritin levels (73 vs. 66 μg/L; p = 0.052). The lowest Hb was measured at the 11th WB donation (152 g/L; p < 0.05) and at the 4th 2RBC apheresis (157 g/L; p < 0.05). There was no deferral due to low Hb at any time. The lowest ferritin was shown at the 4th WB (37 μg/L) and at the 3rd 2RBC donation (60 μg/L), respectively. At the last visit, ferritin was below 15 μg/L in 23 WB donors (8%) and in 2 2RBC donors (1%).

Conclusions

High-intensity male donors with an interdonation interval of 12 weeks for WB donation and 24 weeks for 2RBC apheresis maintain acceptable Hb levels and, after an initial decline, stable ferritin levels despite ongoing blood donation.

Addressing gaps in international blood availability and transfusion safety in low- and middle-income countries: a NHLBI workshop

In April 2017, a workshop sponsored by the National Heart, Lung, and Blood Institute, Division of Blood Diseases and Resources, and the Center for Translation Research and Implementation Science was held to discuss blood availability and transfusion safety in low- and middle-income countries (LMICs). The purpose of the workshop was to identify research opportunities for implementation science (IS) to improve the availability of safe blood and blood components and transfusion practices in LMICs. IS describes the late stages of the translational research spectrum and studies optimal and sustainable strategies to deliver proven-effective interventions. Regional working groups were formed to focus on opportunities and challenges in East Africa, Central/West Africa, Middle East and North Africa, Latin America and the Caribbean, Southeast Asia, Western Pacific Asia, Eastern Europe, and Central Asia. The need for an "adequate supply of safe blood" emerged as the major overriding theme. Among the regional working groups, common cross-cutting themes were evident. The majority of research questions, priorities, and strategies fell into the categories of blood availability, blood transfusion safety, appropriate use of blood, quality systems, health economics and budgeting, and training and education in IS. The workshop also brought into focus inadequate country-level data that can be used as the basis for IS initiatives. A mixed approach of needs assessment and targeted interventions with sufficient evidence base to move toward sustainment is an appropriate next step for blood availability and transfusion safety research in LMICs.

Laboratory and genetic assessment of iron deficiency in blood donors

More than 9 million individuals donate blood annually in the United States. Between 200 and 250 mg of iron is removed with each whole blood donation, reflecting losses from the hemoglobin in red blood cells. Replenishment of iron stores takes many months, leading to a high rate of iron depletion. In an effort to better identify and prevent iron deficiency, blood collection centers are now considering various strategies to manage donor iron loss. This article highlights laboratory and genetic tests to assess the iron status of blood donors and their applicability as screening tests for blood donation.

Blood donor iron status: are we bleeding them dry?

PURPOSE OF REVIEW

This review examines the recent research on the prevalence, determinants and importance of low iron in blood donors, and on the efforts to reduce or prevent iron depletion in donor populations.

RECENT FINDINGS

Female donors, especially younger women, are at highest risk for donation-induced low iron, but menopausal women and high-frequency donors of both sexes also face considerable risk for iron depletion. Predonation screening for hemoglobin contributes little information on donor iron status. Consumption of supplemental iron is helpful in preventing or reversing low iron, and waiting longer between donations also facilitates the recovery of the iron lost through donation.

SUMMARY

Although the impact of phlebotomy-related iron depletion on donor health requires better documentation, measures are available now that can be deployed on a targeted or standardized basis. Blood centers, regulators, and donors should continue to evaluate different approaches for addressing this problem, with the likely outcome that no single measure is optimal for maintaining adequate collections while safeguarding donor health.

Low hemoglobin deferral in blood donors

Low hemoglobin deferral occurs in about 10% of attempted whole blood donations and commonly is a consequence of iron deficiency anemia. Pre-menopausal women often have iron deficiency anemia caused by menstruation and pregnancy and have low hemoglobin deferral on their first donation attempt. Frequent donors also develop iron deficiency and iron deficiency anemia because blood donation removes a large amount of iron from the donor and the 56-day minimum inter-donation interval for donors in the United States is not sufficient for recovery of hemoglobin and iron stores. Other causes for low hemoglobin deferral range from a medically insignificant deferral of a woman with hemoglobin between 12.0 and 12.4 g/dL, which is within the normal reference range but below the 12.5 g/dL needed to donate blood, to anemia caused by an unrecognized malignancy in a "healthy" individual attempting to donate blood. The diverse causes of anemia in blood donors make it difficult to provide accurate information to donors about the cause of their low hemoglobin deferral and complicate implementation of programs to prevent them by blood collecting agencies. This article reviews how hemoglobin is measured and the demographics and causes of low hemoglobin deferral in blood donors. It provides recommendations for how blood collection agencies can provide donors with accurate information about the cause of their deferral and discusses programs that can be implemented to decrease these deferrals in regular donors.

Usefulness of preprocedural levels of advanced glycation end products to predict restenosis in patients with controlled diabetes mellitus undergoing drug-eluting stent implantation for stable angina pectoris (from the Prospective ARMYDA-AGEs Study)

Diabetes mellitus (DM) remains the main predictor of restenosis rates and cardiovascular events following successful percutaneous coronary intervention (PCI) despite the use of drug-eluting stents (DES). HbA1c <6.0% is considered an index of optimized metabolic control in patients with DM, but several studies are downsizing its role in the clinical management of these patients. Increasing evidence points at the role of advanced glycation end products (AGEs) in restenosis pathogenesis independently on Hb1AC levels. Thus, we investigated the predictive value of preprocedural AGE levels for in-stent restenosis in a population of euglycaemic diabetic patients undergoing PCI with DES implantation. One hundred twenty-five consecutive patients with DM in optimized glycemic control admitted for stable angina pectoris and treated with elective DES implantation at a tertiary hospital were prospectively included. The primary end point of the ARMYDA-AGEs study was to compare rates of angiographic ISR at 6 months after the intervention according to pre-PCI levels of AGEs. Secondary end points were the correlations of AGE levels with occurrence of periprocedural myocardial damage, major adverse cardiac events, and in-stent late loss at 6-month control coronary angiography. AGE levels >17 μM was found to be an independent predictor of ISR at 6 months and stent lumen loss. AGEs failed to predict occurrence of secondary endpoints. In conclusion, elevated AGE levels predict occurrence of in-stent restenosis after DES implantation in patients with DM on optimized glycemic control and might represent a dosable marker of adverse outcome after PCI.