The EIRA Study: Vaccinations and RA Risk – no Association found!
“Common adult immunizations are not associated with an increased risk of developing rheumatoid arthritis” – that is the result of research published in the October issue of The Annals of the Rheumatic Disease, the EULAR journal. Last week that data were also presented at the American College of Rheumatology ACR Annual Scientific Meeting (took place from 6th to 11th November).
“Vaccinations are among the events which have long been postulated as inciting agents for rheumatoid arthritis, as well as for many other chronic inflammatory diseases of unknown origin,” lead investigator in the study, Camilla Bengtsson, PhD, stated in her lecture last Monday at the Georgia World Congress Center in Atlanta, USA.
No increased RA risk following immunizations
“In our case-control study including incident cases of newly diagnosed rheumatoid arthritis, no increased risk of RA following immunization was observed, at least not in the five years prior to disease onset”, the epidemiologist at the Institute of Environmental Medicine at Karolinska Institutet in Stockholm, Sweden, explained in more detail, noting that the study is still ongoing. From Dr. Bengtsson’s point of view these results are indicating that immunological provocation with commonly used vaccines in their present form do not carry a risk of rheumatoid arthritis in adults.
“Since rheumatoid arthritis has a hereditary component, our results are reassuring, not only for the population in general, but especially for children and other relatives of patients with RA,” the Swedish lead investigator said at the 2010 ACR scientific meeting.
The EIRA study: genes, environmental factors, and RA risk
The data is based on the Epidemiological Investigation of Rheumatoid Arthritis, the EIRA study. That study, Camilla Bengtsson explained in more fully, is an ongoing, population-based, case-control study in Sweden designed to investigate associations between genes as well as environmental factors and the risk of developing rheumatoid arthritis. The EIRA study began in 1996 and includes scientific data from more than 8,000 subjects. That means that the EIRA study is one of the largest etiological rheumatoid arthritis studies in the world, according to Camilla Bengtsson’s lecture at the 2010 ACR scientific meeting.
Common adult immunizations are not associated with an increased risk of developing rheumatoid arthritis. – Camilla Bengtsson, PhD, lead investigator
And this is how the researchers have designed the vaccination study: They compared 1,998 rheumatoid arthritis patients who were immunized within the five years prior to disease onset to 2,252 participants with rheumatoid arthritis (RA) who were not vaccinated. Each group was matched based on age, gender and place of residence, and all participants were between 18 and 70 years old.
Camilla Bengtsson and co-workers found no association between injections and the development of rheumatoid arthritis. Furthermore, they found no association between any specific vaccine – e.g., influenza and tetanus vaccination, diphtheria inoculation, tick-borne encephalitis, hepatitis A, B, C together, polio vaccination, flu shots, or pneumococcus vaccination – and the risk of developing rheumatoid arthritis.
From a scientific point of view it is an interesting approach, I think, that the study also examined whether vaccinations have a different impact on two groups of participants. Camilla Bengtsson and co-workers examined those subjects with ACPA-positive and those with ACPA-negative rheumatoid arthritis – and they found that the vaccines did not increase the risk of either disease form.
The ACPAs, or “anti-citrullinated protein antibodies”, are autoantibodies frequently detected in the blood of patients suffering from rheumatoid arthritis. These autoantibodies have proven to be powerful biomarkers of rheumatoid arthritis, and ACPA testing has become a commonly accepted and crucial part of diagnosing the autoimmune disease. Recently, ACPA testing even has become an ACR and EULAR criterion for rheumatoid arthritis classification (see the posts on ORGENTEC Autoimmunity Blog on 24/08/2010: New Classification Criteria for Rheumatoid Arthritis (RA) and the article The 2010 ACR-EULAR Rheumatoid Arthritis Classification Criteria, posted on 06/09/2010.)
In our case-control study including incident cases of newly diagnosed RA, no increased risk of RA following immunization was observed, at least not in the five years prior to disease onset.” – Camilla Bengtsson, PhD, lead investigator
By the way: You will find more information on ACPAs and ACPA testing in the respecting wikipedia article. Furthermore, you will find a bibliographical reference on Anti-MCV and antibodies against citrullinated protein/peptide antigens (ACPA) on the ORGENTEC website. I have to admit that it has been a while I have updated that list of literature about the ACPA topic. But it still is current, and I will take the opportunity to revise that list soon.
Genes of RA susceptibility, environmental factors and vaccinations – risk for RA?
Let’s go back to the results of the Swedish EIRA study group. – The researchers did also investigate the association between genes as well as environmental factors and the risk of developing RA. Finally, they noted that vaccinations did not elevate the risk of developing rheumatoid arthritis among participants who smoke and among participants who are carriers of HLA-DRB1 SE alleles both of which are established risk factors of rheumatoid arthritis.
Concerning the topic “cigarette smoking and rheumatoid arthritis”, see my article posted on the ORGENTEC Autoimmunity Blog on 21/05/2010: There is a Connection between Rheumatoid Arthritis (RA) and Smoking – what are the Reasons? and the Research Update article by my colleague Friederike Hammar posted on 07/04/2010: Genetics of Rheumatoid Arthritis Susceptibility . .
Author of this article: Tobias Stolzenberg
- Aletaha D, Neogi T, Silman AJ, Funovits J, Felson DT, Bingham CO 3rd, Birnbaum NS, Burmester GR, Bykerk VP, Cohen MD, Combe B, Costenbader KH, Dougados M, Emery P, Ferraccioli G, Hazes JM, Hobbs K, Huizinga TW, Kavanaugh A, Kay J, Kvien TK, Laing T, Mease P, Ménard HA, Moreland LW, Naden RL, Pincus T, Smolen JS, Stanislawska-Biernat E, Symmons D, Tak PP, Upchurch KS, Vencovsky J, Wolfe F, Hawker G. The 2010 ACR-EULAR classification criteria for rheumatoid arthritis. Ann Rheum Dis. 2010 Sep;69(9):1580-8 – the link is to the full text article in the EULAR Journal, accessed 12/11/2010
- Bengtsson C, Kapetanovic MC, H Källberg, Sverdrup B, Nordmark B, Klareskog L, Alfredson L, EIRA Study Group. Common vaccinations among adults do not increase the risk of developing rheumatoid arthritis: results from the Swedish EIRA study. Concise Report. Ann Rheum Dis 2010;69:1831-1833 doi:10.1136/ard.2010.129908. – the link is to the abstract, accessed 12/11/2010
- ORGENTEC’s Literature Service: List of recommended reading on anti-citrullinated protein antibodies: recommended reading on anti-mutated citrullinated vimentin antibodies (Anti-MCV) and anti-citrullinated protein antibodies (ACPA) on the ORGENTEC Diagnostika website
- website of The American Congress of Rheumatology, ACR
- website of the website of the EIRA Study Group (Epidemiological Investigation of Rheumatoid Arthritis)