ROME — Immunization with common vaccines is not associated with an increased risk for rheumatoid arthritis, nor does it trigger the autoimmune disease in individuals who have established risk factors, according to an analysis of data that was presented by Camilla Bengtsson.
Using data from the Swedish population-based EIRA (Epidemiological Investigation of Rheumatoid Arthritis) data set and 1,984 healthy matched controls, Ms. Bengtsson, a doctoral candidate at the Karolinska Institute in Stockholm, and her associates compared the 582 individuals in the EIRA data set who had been vaccinated in the 5 years prior to disease onset with the 1,269 RA patients who had not been vaccinated within 5 years prior to disease onset. Among the control subjects, 617 had been vaccinated and 1,367 had not been vaccinated within the preceding 5 years.
Vaccine by vaccine, the odds ratio for developing RA after influenza vaccination was 1.1 (252 RA patients and 279 controls had received the flu vaccine during the period of interest). The OR for RA after tetanus vaccination was 1.0 (170 cases and 179 controls had received that vaccination). The OR was 1.0 for diphtheria vaccination (71 cases/71 controls). For tick-borne encephalitis, the OR was 0.8 (91 cases/122 controls). The OR for hepatitis A, B, and C was 0.9 (105 cases/124 controls). The OR for polio vaccination was 1.1 (29 cases/31 controls). The OR for pneumococcus was 1.0 (22 cases/22 controls). The RA OR for the unvaccinated was 1.0 (1,269 cases/1,367 controls). She reported having no conflicts.