The sex of the red blood cell donor does not have a significant impact on the mortality of transfusion recipients

Key points to remember:

• Laboratory evidence and observational studies had suggested an advantage of a male donor strategy.
• Further trials are needed to investigate other potential donor characteristics.

According to the results of a study published in Jhe New England Journal of Medicine.

Results from previous observational studies have suggested that recipients of red blood cells from female donors may have poorer survival outcomes than those who received red blood cells from male donors, but evidence to guide transfusion strategies was limited.

Dean A. Fergusson

“I was surprised that we didn’t find any advantage to a male dealer strategy over [with] a female donor strategy, as laboratory evidence and our observational studies and those of others have indicated a significant benefit,” Dean A. Fergusson, MHA, PhD, FCAHS, senior scientist and director of the clinical epidemiology program at the Ottawa Hospital Research Institute, Healio told Healio. “This demonstrates the power and necessity of randomized controlled trials to answer important questions.”

Methodology and results

Fergusson and colleagues conducted the multicenter, double-blind trial assessing donor sex on recipient mortality among 8,719 hospitalized patients (median age, 69 years; interquartile range, 58-78) randomly assigned to receive red blood cell units from male (n=5190) or female (n=3529) donors. The 60:40 ratio matched the historical allocation of red blood cell units from the blood supplier.

Most patients (79.9%) received their first transfusion for impatience, and among them, 2942 (42.2%) had already been admitted to a surgical department.

The patients had an initial hemoglobin level before the first transfusion of 79.5 ± 19.7 g/L. Those in the female donor group received an average of 5.4 ± 10.5 units of red blood cells, while those in the male donor group received an average of 5.1 ± 8.9 units (difference = 0.3 units; 95% CI, 0.1 to 0.7).

Survival served as the primary outcome, with the male donor group as the reference group.

During the trial, 1712 patients in the male donor group and 1141 patients in the female donor group died (adjusted RR for death = 0.98; 95% CI, 0.91-1.06). The researchers observed no difference between the groups in the secondary outcomes, although they noted a higher incidence of MRSA infection among the female donor group (HR=2; 95% CI, 1 ,15-3.46).

Limitations of the study included a potential lack of generalizability of the results to other jurisdictions that have significantly different blood bank practices or red blood cell products.

Next steps

Further testing may identify donor characteristics other than gender that can have a significant impact on recipient survival, Fergusson said.

“Our data confirms that current blood collection, blood banking and clinical practices do not need to be changed, as male donors confer no clinical benefit,” he told Healio. “Next steps would be to assess other donor characteristics such as donor age and their effect on recipient outcomes.”

For more information:

Dean A. Fergusson, MHA, PhD, FCAHS, can be reached at the Center for Research on Changing Practice, Ottawa Hospital Research Institute, 501 Smyth Road, Box 201B, Ottawa, ON K1H 8L6; email: [email protected].