Behçet Disease Associated With Increased Risk for Psoriasis and Psoriatic Arthritis

Behçet disease is a rare disorder in the United States with unknown etiology, and typically has a higher incidence in the areas between the Eastern Mediterranean Basin and the Middle East. Behçet disease shares characteristics with psoriasis in that they are both chronic, relapsing inflammatory skin diseases accompanied by joint involvement as well as other systemic manifestations. Despite these similarities, it is unknown whether Behçet disease and psoriasis are related.

Researchers conducted the current analysis to examine the link between Behçet disease and psoriasis/PsA in a large cohort of patients in the National Health Insurance Service of Korea database between 2002 and 2015.

The following cohort definitions were used to select patients for the study from the database, which included 1,113,656 registered individuals:

• Behçet disease cohort (n=2230): patients with Behçet disease with at least 2 consecutive visits within 6 months and a documented pathergy test.
• Psoriasis cohort (n=17,362): patients with psoriasis with at least 2 consecutive visits within 6 months and with a prescription of topical treatment, UV therapy, or oral medication for at least 3 consecutive months.
• PsA cohort (n=3664): patients with PsA with at least 2 consecutive visits, with each visit being at least 6 months apart; with antibody testing or HLA-B27 typing; or receiving treatment with disease-modifying antirheumatic drugs/biologics.

Researchers determined statistical relationships between Behçet disease and psoriasis/PsA using chi-square and binary logistic regression analyses, adjusted for sex, age, and gross income level.

Results showed that patients with Behçet disease were approximately 3 times more likely to be diagnosed with psoriasis (adjusted odds ratio [aOR], 2.36; 95% CI, 1.91-2.93; P <.001) and twice as likely to be diagnosed with PsA (aOR, 2.19; 95% CI, 1.42-3.38; P <.001). In addition, men (aOR, 1.19; 95% CI, 1.16-1.23; P <.001) and individuals aged 65 years or more (aOR, 1.51; 95% CI, 1.43-1.59; P <.001) with psoriasis were significantly more likely to be affected by Behçet disease.

On the other hand, compared with men with PsA, women with PsA were at higher risk of developing Behçet disease (aOR, 2.02; 95% CI, 1.88-2.16; P <.001). As in the case of the psoriasis cohort, older patients with Behçet disease were observed to be at greater risk for PsA (aOR, 3.13; 95% CI, 2.90-3.40; P <.001)

Researchers also noted an association between body mass index (BMI) and risk for Behçet disease; patients with a BMI of 30 to 35 had an aOR of 1.24 (95% CI, 1.12-1.38; P <.001)

Study limitations included a lack of information regarding disease severity or clinical subtypes, potential bias in the cohort because the data were derived from hospital-based records, and a small sample size of patients with PsA (n=21) who were also affected by Behçet disease.

“In summing up, the current investigation has backed up the long-held speculation about a potential immunological link between [Behçet disease] and [psoriasis] with a solid, population-based evidence,” the researchers wrote. “Further studies are warranted to elucidate the mechanism behind this disease interaction and apply the insight for better-guided clinical practice.”

Reference

Hahn HJ, Kwak SG, Kim DK, Kim JY. Association of Behçet disease with psoriasis and psoriatic arthritis. Sci Rep. Published online January 28, 2021. doi:10.1038/s41598-021-81972-4