Clinical, Laboratory, and Imaging Features Between Men and Women With Axial Spondyloarthritis in a Specialized Center in Argentina.

Objectives: The aims were to estimate the frequency of axial spondyloarthritis (axSpA) in women and to analyze the clinical, laboratory, and imaging differences with respect to men at the time of diagnosis.

Methods: Consecutive patients older than 18 years with a diagnosis of axSpA admitted to the "Reumacheck" SpA program were included between 2017 and 2022. At baseline, all patients underwent clinical assessment, laboratory tests including C-reactive protein and human leukocyte antigen B27, and imaging (plain radiography and magnetic resonance imaging of sacroiliac joints, and ultrasound of heel entheses). All evaluators were blinded to the results of the other evaluations.

Results: One hundred sixteen patients with a diagnosis of axSpA were included. The frequency at diagnosis in women was 61.55%. In the univariate analysis, the significant differences between women and men at diagnosis of axSpA were good response to nonsteroidal anti-inflammatory drugs, elevated C-reactive protein, New York Criteria (+), enthesis ultrasound (+), years of education, number of swollen joints, erythrosedimentation rate, and the very low frequency of bone bridges in the magnetic resonance imaging of the sacroiliac joints. In the logistic regression analysis, the dependent variable was "men," and the only feature that was independently associated was having radiographic compromise according to the New York criteria (odds ratio, 2.6).

Conclusions: The frequency of axSpA in women was 61.55%; clinical, laboratory, and imaging differences were observed. Women experienced less radiographic compromise.