This article is more than 5 years old. Information may no longer be current.
Blood donors do not transmit neurodegenerative diseases to transfusion recipients
Click Here to Manage Email Alerts
Patients who receive blood transfusions from donors who later develop neurodegenerative disorders are at low to no risk for the transmission of these diseases, according to a retrospective cohort study published in Annals of Internal Medicine.
The aggregation of aberrantly polymerized, misfolded proteins in the brain occurs with several neurodegenerative disorders, including Alzheimer disease, Parkinson disease, amyotrophic lateral sclerosis (ALS) and other dementia-related disorders. Further, protein aggregation has been found to have similarities with prion diseases.
“Although animal models have not shown transmission of misfolded proteins through blood transfusion, concern has been raised that the similarity with prion diseases may extend to this route of transmission, especially given that variant Creutzfeldt–Jakob disease is transmissible through blood transfusion,” Gustaf Edgren, MD, PhD, from the department of medial epidemiology and biostatistics at Karolinska Institutet, and colleagues wrote.
To investigate the potential for transfusion transmission of neurodegenerative disorders, the researchers used data from the SCANDAT2 database, which houses information on blood donations, transfusions and donor-recipient links in Denmark and Sweden.
Of over 1.4 million blood transfusion recipients included in the analysis, 2.9% received at least one transfusion from a donor diagnosed with a neurodegenerative disorder within 20 years after donation. This included donors with dementia of any type (1.8%), Parkinson disease (1%), Alzheimer disease (0.8%) and ALS (0.3%).
Recipients exposed to blood from affected donors did not appear at greater risk for dementia of any type (HR = 1.04; 95% CI, 0.99-1.09), Alzheimer disease (HR = 0.99; 95% CI, 0.85-1.15) or Parkinson disease (HR = 0.94; 95% CI, 0.78-1.14) compared with patients who received blood from healthy donors.
Further, researchers found no evidence of transmission of any neurodegenerative diseases in analyses that considered disease concordance between donors and their recipients. This remained true when they tested for disease concordance between recipients of multiple blood transfusions from the same donor.
Edgren and colleagues acknowledged the study was limited by its observational study design, underascertainment of the outcome, and possible insufficient statistical power.
“Although our findings do not formally exclude the possibility of neurodegenerative diseases being transmissible via transfusion, they do offer reassurance for the fields of transfusion medicine and general medicine and for transfusion recipients in showing that such transmission must at least be rare or result in average induction times exceeding 20 years,” they wrote. – by Kristie L. Kahl
Disclosure: Edgren reports no relevant financial disclosures. Other researchers report grants from the Danish Council for Independent Research, the Swedish Heart-Lung Foundation and the Swedish Research Council during the conduct of the study.
Click Here to Manage Email Alerts