New biomarkers are identifying an increasing number of women with spondyloarthritis, contrary to the idea that the disease affects mostly men. New research shows that severity and inflammatory lesions differ between the sexes.
Tournadre A, Pereira B, Lhoste A et al. Differences between women and men with recent onset axial spondyloarthritis: Results from the DESIR cohort, (2013) Arthritis Care and Research, accepted article: DOI: 10.1002/acr.22001
The emergence of new and more sensitive diagnostic and prognostic markers, such as positivity for the gene HLAB27, have resulted in increasing numbers of women being diagnosed with ankylosing spondylitis (AS). This contradicts the notion that AS affects mostly men, and may explain why women are underdiagnosed.
French researchers find that women with early axial spondyloarthritis (SpA, which falls under the umbrella of AS), have less evidence of radiological abnormalities than men, but greater disease activity and worse functioning.
The researchers studied 239 men and 236 women in a prospective multicenter study of patients with early inflammatory back pain suggestive of SpA who fulfilled the Assessment of SpondyloArthritis International Society (ASAS) classification criteria. Not only did women with SpA have more self-reported disease activity as measured by the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), but also greater fatigue and worse functioning, although fewer inflammatory lesions were visible on imaging.
Women with sacroiliitis had more peripheral involvement, higher tender and swollen joint counts and enthesitis scores (perhaps indicating associated fibromyalgia), and a lower quality of life compared with men.
Women with early axial SpA also had a greater incidence of family histories of psoriasis, Crohn’s disease and ulcerative colitis, supporting the idea that females may require higher genetic load to develop the disease.
Radiographic sacroiliitis and MRI-evident inflammatory lesions of the sacroiliac joints and/or spine were significantly more frequent in men. Men also had increased HLAB27 positivity and elevated C-reactive protein. There were no significant gender differences in disease duration.
The researchers say differences in disease expression and presentation may play a role in missed or delayed diagnosis among women, as well as affecting the perception that biologic therapy with TNF inhibitors works better in men with this condition.