TUESDAY, Aug. 6, 2019 (HealthDay News) -- Evidence shows that vaccination is not associated with an increased risk for being diagnosed with multiple sclerosis (MS) within the next five years, according to a study published online July 30 in Neurology.
Alexander Hapfelmeier, Ph.D., from the Technical University of Munich, and colleagues used ambulatory claims data for 12,262 individuals from the Bavarian Association of Statutory Health Insurance Physicians covering 2005 to 2017 to examine the correlation between MS and vaccinations in the first years preceding diagnosis. Participants newly diagnosed with Crohn disease or psoriasis (19,296 and 112,292 participants, respectively) and those with no history of these autoimmune diseases (79,185 individuals) served as controls.
The researchers found that the odds of MS were lower in participants with a recorded vaccination compared with those without autoimmune disease, with Crohn disease, and with psoriasis (odds ratios, 0.870 [95 percent confidence interval (CI), 0.837 to 0.904; P < 0.001], 0.919 [95 percent CI, 0.876 to 0.963; P < 0.001], and 0.973 [95 percent CI, 0.936 to 1.012; P = 0.177], respectively). The most pronounced lower odds were seen for vaccinations against influenza and tick-borne encephalitis. These effects were consistent across different time frames, control cohorts, and definitions of the MS cohort. Increased effect sizes were seen toward the time of first diagnosis.
"These data alone do not allow for any conclusion regarding a possible protective effect of vaccinations regarding the development of MS," the authors write. "However, our results do not support the assumption that vaccinations are a risk factor for the development of MS."
Two authors disclosed financial ties to the biopharmaceutical industry; one author holds two relevant patents.