Rosacea in women is linked with an increased risk for a wide variety of autoimmune disorders including type 1 diabetes, celiac disease, multiple sclerosis, and rheumatoid arthritis, according to a large population-based case-control study.

The finding expands the association of rosacea and autoimmune diseases beyond the previously reported associations with type 1 diabetes and celiac disease, reported Dr. Alexander Egeberg of Herlev and Gentofte Hospital, University of Copenhagen, and colleagues ( J Am Acad Dermatol. 2016;74:667-72 .)

“Remember that the absolute risk is still low; having rosacea does not guarantee that patients will develop other autoimmune diseases, and vice versa,” Dr. Egeberg said in an interview. “The links may provide insight into the pathogenesis of these diseases, and it will be interesting to see if systemic treatment of rosacea also affects the autoimmune diseases and the other way around.”

Using Danish registered health records, the researchers found 6,759 patients with rosacea, and matched them by age and sex to 33,795 control subjects. About two-thirds of the patients were women.

Compared with their matched controls, people with rosacea were at least twice as likely to have type 1 diabetes, celiac disease, and rheumatoid arthritis (odds ratio 2.6 for type 1 diabetes, 2.0 for celiac disease, and 2.1 for rheumatoid arthritis) and 1.65 times as likely to have multiple sclerosis. The differences, with the exception of rheumatoid arthritis, were statistically significant only in women.

The researchers said the broader association with autoimmune comorbidities is “intriguing” and suggests the genetic component of rosacea could be stronger than previously assumed with autoimmune inflammatory pathways contributing to the disease course. Because distinct rosacea subtypes (erythematotelangiectatic, papulopustular, phymatous, and ocular) could be associated with specific comorbidities, future association studies should attempt to stratify for clinical subtypes of rosacea, they noted.