The effect of ferritin-guided iron supplementation among Danish female first-time blood donors.

BACKGROUND: The identification of blood donors at risk of developing low hemoglobin (Hb) and subsequent intervention is expected to reduce donation-induced iron deficiency and low Hb among blood donors. This study explores the effects of ferritin-guided iron supplementation for female first-time donors implemented in four of five administrative regions in Denmark. STUDY DESIGN AND METHODS: We included 45,919 female first-time donors in this study. Hb values were determined in donations of included donors during a 2-year follow-up period. For each region, an intervention group (after implementation) and a control group (before implementation) were defined. The primary outcome was Hb below the donation threshold (7.8 mmol/L ~ 12.5 g/dL) at the time of donation, in the control group, and the intervention group, using logistic regression. The secondary outcome was the number of donations per donor given during the follow-up period. RESULTS: We observed a statistically significant decrease in the risk of female first-time donors experiencing a donation with low Hb after ferritin-guided iron supplementation was introduced: Odds ratio, 0.82; 95% confidence interval (CI), 0.71-0.95. We found a statistically significant increase in the number of donations per donor during the follow-up period after intervention; rate ratio: 1.05, 95% CI: 1.02-1.08. DISCUSSION: Ferritin-guided iron supplementation led to a significant reduction in the occurrence of low hemoglobin (Hb) levels among Danish female first-time blood donors. The intervention was additionally associated with an increase in the number of donations per donor.

Oral iron supplementation is not associated with short-term risk of infections: results from the Danish Blood Donor Study.

BACKGROUND: Blood donors are at increased risk of developing iron deficiency, and several studies have recommended iron supplementation for this group. The aim of this study was to investigate the effect of oral iron supplementation on risk of infections among healthy blood donors. STUDY DESIGN AND METHODS: We included 82,062 participants from the Danish Blood Donor Study who completed a questionnaire on health-related items including use of oral iron supplementation. Infection outcomes were ascertained by using ICD-10 codes in the Danish National Patient Register and Anatomical Therapeutic Chemical codes in the Danish Prescription Register. Multivariable Cox proportional hazards analysis was used as the statistical model. Risk estimates are presented as crude hazard ratios (HRs) with 95% confidence intervals (CIs). RESULTS: During 19,978 person-years of observation, 6983 donors redeemed at least one prescription of antimicrobials. Similarly, during 19,829 person-years of observation, 242 donors were treated for infection at a hospital. Use of oral iron supplementation was not associated with redeemed prescriptions of antimicrobials in any strata: premenopausal women-HR 1.00, 95% CI 0.91-1.10; postmenopausal women-HR 1.07, 95% CI 0.87-1.32; and men-HR 1.01, 95% CI 0.84-1.21. In addition, use of oral iron supplementation was not associated with risk of hospital-based treatment for infection. CONCLUSION: In a large cohort of blood donors, use of oral iron supplementation was not associated with subsequent short-term risk of infection. These findings are important to help understanding the safety of using oral iron supplementation among blood donors and the general population.