The Prevalence of Atopy in Biologically Treated Spondyloarthropathies: A Retrospective Study of 200 Patients

(1) Background: Recent data shed light on the association between atopic disorders (ADs) (atopic dermatitis, allergic asthma, allergic rhinitis) and spondyloarthropathies (SpAs), underpinning the critical role of T helper (Th)1-Th17/Th2-T regulatory cells disbalance. We evaluated the prevalence of AD in axial SpAs (axSpAs) and psoriatic arthritis (PsA) and explored the potential association between atopic status, disease-related parameters, and biological therapy. (2) Methods: A monocentric, retrospective study was conducted that enrolled 200 patients taking biologics. Demographics, disease, and drug-related variables, along with a screening questionnaire focused on Ads, were systematically collected. (3) Results: Overall, 51 patients (25.5%) had atopy—namely, 24.4% of axSpA and 28% of PsA, with a higher frequency of rhinitis (43%) vs. atopic dermatitis (37.2%) or asthma (21.5%). We failed to demonstrate any statistically significant difference in demographics, SpA-related parameters excepting concomitant inflammatory bowel disease, and biologic drug exposure in patients with and without atopy (p > 0.05). However, significantly more non-atopic patients need only one TNF inhibitor (54%) vs. atopic patients (28%) (p < 0.05) to control active SpA. (4) Conclusions: We successfully demonstrated that AD is associated with one out of four SpA. Irrespective of the SpA subtype, atopic patients require more frequent switching among biologics, as significantly more non-atopic patients remain on their first anti-TNF.