Ankylosing spondylitis: an Australian experience

Background: The purpose of this study was to characterize an Australian cohort of ankylosing spondylitis (AS) patients and examine predictors of important disease outcomes. Methods: Cross-sectional study of first visit data among patients referred to the Austin Spondylitis Clinic from rheumatology or general practices. We obtained clinical and laboratory data and validated composite indices through self-reported questionnaire. Results: Delay in AS diagnosis averaged 8.1 years and was higher among women and younger-onset disease. Cervicothoracic mobility was better in women although they showed more entheseal tender points and greater impairment of quality of life. Those with long-standing AS had similar disease activity to recent onset disease but had greater functional disability. Current smoking was associated with worse outcomes although there was no association between cumulative exposure and AS outcomes. Conclusion: The clinical expression of AS in this first-described Australian cohort is similar to previously described cohorts. We observed greater cervicothoracic mobility and a higher enthesitis index among women perhaps contributing to longer delay to diagnosis.