Rheumatoid arthritis does not get transmitted through blood transfusions, according to findings from a large retrospective study of blood transfusions in Denmark and Sweden.
Two separate analyses showed that the risk of developing RA among transfusion recipients was not correlated to the presence of RA in the blood donor.
There had been concern about risks of transfusion because of RA’s long preclinical phase, in which RA pathogenesis factors circulate in the periphery and could potentially be transmitted in a transfusion. Mouse models had suggested that anti–citrullinated peptide/protein antibodies could spark or worsen arthritis, and RA fibroblast-like synoviocyte cell precursors could spread RA between joints.
Two previous studies, based on self-reported history of blood transfusion, reached the opposite conclusion regarding the risk of RA transmission.
The latest findings, published online in Annals of the Rheumatic Diseases , involved an analysis of data from the Danish–Swedish population-based research donations and transfusions database (SCANDAT2). In one model, they looked at 938,942 blood donors, 2,412 of whom were diagnosed with RA during the follow-up period. The researchers then analyzed data from 13,369 subjects who had been exposed to blood from donors who went on to develop RA, and compared them to 139,470 recipients who received blood from donors who did not develop RA. There was no statistically significant correlation between risk of RA among recipients by RA status of the donors, RA serotype in the donors, donor age at RA diagnosis, or elapsed time between donation and RA diagnosis.
In a second analysis, the researchers looked for RA clusters among recipients who might have received blood from a donor with RA. They found no association between RA risk for a given recipient based on whether other recipients from the same donor had gone on to develop RA.
“In light of the study’s strengths, including low likelihood of confounding and large study size ensuring meaningful statistical power, we believe the possibility of RA transmission is unlikely to be clinically relevant,” the authors wrote.
The study was funded by the Danish Rheumatism Association, the Odense University Hospital PhD Fund and Fund for clinical research, the Nordic Cancer Union, the Swedish Foundation for Strategic Research, the Swedish Research Council, and ALF funds. One author reported receiving grants from AbbVie, Bristol-Myers Squibb, Merck, Pfizer, Roche, Samsung, and UCB.
SOURCE: Just SA et al. Ann Rheum Dis. 2018 Mar 1. doi: 10.1136/annrheumdis-2017-212844