Infections tied to increased risk for Sjögren’s syndrome
medwireNews: Individuals with primary Sjögren’s syndrome (pSS) are almost twice as likely to have experienced an infection requiring hospital care than those without, researchers report.
The registry-based study included 945 Swedish patients with pSS diagnosed between 1987 and 2013 and 9048 controls from the general population matched on age, sex, and geographical location.
As reported in the Journal of Internal Medicine, 21.4% of the pSS patients were hospitalized or required outpatient hospital care as a result of infection over an average period of 16 years prior to pSS diagnosis, compared with just 12.9% of matched controls, giving a significant odds ratio (OR) of 1.9.
When the analysis was broken down by infection type, pSS patients were significantly more likely than controls to have a history of respiratory (OR=2.5), skin (OR=1.7), and urogenital tract (OR=1.7) infections, but rates of gastrointestinal infections were not significantly elevated among those with pSS.
Marie Wahren-Herlenius, from Karolinska Institutet in Stockholm, Sweden, and colleagues note that the association between pSS and prior infection of any type was stronger among patients with Ro/SSA and La/SSB autoantibody-positive disease compared with those without autoantibodies (OR=2.7 vs 1.9), and the same was true for respiratory, skin, and urogenital infections.
Among autoantibody-positive patients, the researchers also demonstrated that the association between infection and pSS was stronger for those with at least two prior infections compared with one infection, which they say points to “a dose-response relationship between infections and autoantibody-positive pSS.”
These results “support the hypothesis that environmental triggers of the immune system are an important part of the etiology of pSS,” write the study authors. They caution, however, that “as we did not have access to serum samples from patients at the time of infection, such a hypothesis remains to be experimentally investigated.”
Writing in a press release, Wahren-Herlenius said: “To design strategies to prevent rheumatic diseases, we need to learn how and why they develop,” adding that these these findings are “a step in that direction.”
medwireNews is an independent medical news service provided by Springer Healthcare. © 2019 Springer Healthcare part of the Springer Nature group