Medical Director Donation Policy & Studies, Canadian Blood Services Ottawa, Ontario, Canada
Background/Case Studies: Iron deficiency is common in repeat female blood donors. One mitigation strategy is to test donors’ ferritin levels and encourage those with a low ferritin level to pause donating and increase iron intake. A possible negative consequence for the blood service is nonreturn of donors informed of their low ferritin levels. We evaluated donor return after implementing selective ferritin testing on female whole blood donors.
Study
Design/Methods: Female whole blood donors were tested at every 10th donation (11th, 21st etc.). All donors were provided their results, with additional communication for those with low (under 25ug/L) or high (over 299 ug/L) ferritin levels. Donors with low ferritin were advised to pause donation for at least 6 months, follow up with their healthcare provider and consider iron supplementation; female donors have a minimum inter-donation interval of 84 days (3 months) for whole blood donation. Data from the donor information system (eProgesa) was analysed to determine ferritin levels, hemoglobin (Hb) deferral rates, and donation visits in female donors who had initial ferritin testing performed between January and June 2023 (6 months) followed until December 31, 2024.
Results/Findings: Out of 8,460 donors tested, 25% had low ferritin. Of these donors, 75% had donated at least 4 times in the previous 2 years, compared to 54% of donors with normal ferritin. Amongst donors with a low ferritin level, 35% returned sooner than 6 months after notification and 40% returned between 6 and 18 months of notification (total return rate=75%). For donors with normal ferritin, the total return rate at 18 months was 87% (see Figure). Low ferritin donors who returned less than 6 months after their notification had a much higher Hb deferral rate of 16% compared to 5% in low ferritin donors who waited longer before returning to donate and 4% in donors with normal ferritin.
Conclusions: One quarter of female donors tested had low ferritin. These donors had a higher donation frequency in the 2 years prior to testing. Some low ferritin donors did pause donation for 6 months and return to donate. However, 35% returned early, often failing their Hb screen. The overall return rate 1.5 years after testing was 12% lower in low ferritin donors compared to female donors with normal ferritin. Ideally, better donor education and messaging would improve the efficacy of this mitigation strategy to maintain both donor health and the adequacy of the blood supply.
