Photo by Elise Amendola
Results of a large, retrospective study suggest that neurological diseases are not transmitted via blood transfusion.
Previous studies have shown that such diseases can be induced in healthy laboratory animals through the injection of diseased brain tissue from humans.
This has caused concern that neurological diseases might be transmitted from human to human via blood transfusions.
However, a study published in Annals of Internal Medicine suggests such transmission does not occur.
“The results are unusually clear for such a complicated subject as this,” said study author Gustaf Edgren, PhD, of Karolinska Institutet in Stockholm, Sweden.
“We’ve been working with this question for a long time now and have found no indication that these diseases can be transmitted via transfusions.”
Dr Edgren and his colleagues conducted this study by analyzing data from 1,465,845 patients who received blood transfusions in Sweden or Denmark between 1968 and 2012.
The team used multivariable Cox regression models (taking into account sex, age, place of residence, blood group, number of transfusions, and time since first transfusion) to estimate hazard ratios for dementia of any type, Alzheimer’s disease, and Parkinson’s disease in patients who received transfusions from donors who were later diagnosed with any of these diseases, compared to patients who received blood from healthy donors.
In all, 2.9% of patients received a transfusion from a donor diagnosed with one of the aforementioned neurological diseases. And there was no evidence of disease transmission via transfusion.
The hazard ratio for dementia in transfusion recipients whose donors were diagnosed with dementia, compared to recipients of blood from healthy donors, was 1.04 (95% CI, 0.99 to 1.09).
The hazard ratios for Alzheimer’s disease and Parkinson’s disease were 0.99 (95% CI, 0.85 to 1.15) and 0.94 (95% CI, 0.78 to 1.14), respectively.
“Blood transfusions are extremely safe in the Western world today, but, even so, we are working continuously and proactively on identifying any overlooked risks,” Dr Edgren said.
“The Swedish-Danish database that we have built up and used in many similar studies clearly demonstrates the value of our vast health registries. This kind of study would have simply been extremely difficult anywhere else in the world.”
