Atopic dermatitis was significantly associated with 11 of 22 examined autoimmune diseases and with having multiple autoimmune diseases, especially in smokers, according to study results published in Journal of the American Academy of Dermatology.
The researchers identified 8,112 Danish adults who had been diagnosed with atopic dermatitis between Jan. 1, 1997, and Dec. 31, 2012. These patients were compared with a control group of 40,560 age- and sex-matched individuals. Mean patient age was 42.4 years in both groups.
The autoimmune diseases that were significantly associated with atopic dermatitis included: alopecia areata, vitiligo, chronic urticaria, celiac disease, chronic glomerulonephritis, Sjögren syndrome, systemic lupus erythematosus, ankylosing spondylitis, Crohn's disease, unspecified inflammatory bowel disease, ulcerative colitis and rheumatoid arthritis.
Atopic dermatitis was also found to have a stronger association with having three or fewer autoimmune diseases compared with one or two comorbidities. There were overlapping confidence intervals, though these were still significant.
A history of smoking was significantly associated with having one or more autoimmune disease in patients with atopic dermatitis (P = .001).
According to the researchers, because of the common occurrence of autoimmune comorbidities, especially in patients who smoke, and the association of high living standards and urban lifestyles with atopic dermatitis found in previous studies, atopic dermatitis and autoimmune diseases may have shared genetic risk loci and common environmental triggers.
“Clinicians who care for patients with atopic dermatitis should be aware of the link with autoimmune disease and discourage smoking in their patients,” the researchers concluded. – by Talitha Bennett
Disclosure: The researchers report no relevant financial disclosures.