Red blood cell (RBC) transfusions from either previously pregnant, sex-discordant, or female donors were not significantly associated with higher mortality among transfusion recipients, according to a retrospective analysis of more than 1 million donors.
“This study used data from 3 large cohorts in the United States and Scandinavia to investigate whether blood donor sex and pregnancy history were associated with mortality of transfusion recipients,” wrote Gustaf Edgren, MD, PhD, of Karolinska University Hospital, Stockholm, and colleagues. The findings were published in JAMA.
The researchers analyzed data from three separate cohorts that included a combined 1,047,382 red blood cell transfusion recipients. Data collected included donor-related information, such as sex and pregnancy history, as well as survival data of transfusion recipients. The primary outcome measured was in-hospital mortality, and the secondary outcome was long-term mortality. Data were collected until Dec. 31, 2016.
The researchers found no statistically significant associations between either sex-discordant donors (male donor to female recipient or female donor to male recipient), female donors, or previously pregnant donors and in-hospital mortality of transfusion recipients.
The hazard ratio estimates for each unit transfused from a previously pregnant donor ranged from 1.00-1.01 in the three cohorts. Similarly, the HR estimates ranged from 0.99-1.00 for female donors in the three cohorts and 0.99-1.02 for sex discordant donors.
The only significant association found was observed in the smallest cohort of 34,662 recipients. Researchers found an increased risk of death in patients who received one to two sex discordant transfusions (HR, 1.08; 95% confidence interval, 1.03-1.14) or five to six transfusions (HR, 1.14; 95%CI, 1.01-1.29), compared with recipients who received no sex-discordant transfusions.
“The results are reassuring in that the survival of patients who got transfused with red blood cells does not appear to be associated with whether the blood they received was donated by a man, by a woman who had been pregnant — or by one who had not. That’s important to know,” Simone Glynn, MD, chief of the Blood Epidemiology and Clinical Therapeutics Branch at the National Heart, Lung, and Blood Institute, as well as a study author, said in a statement.
The study was funded by the National Heart, Lung, and Blood Institute. The authors reported financial disclosures related to the National Institutes of Health, RTI International, Cerus, AABB, Creative Testing Solutions, and the Nordic Cancer Union.
SOURCE: Edgren G et al. JAMA. 2019 Jun 11. doi: 10.1001/jama.2019.7084.