Clinical Spectrum of Ankylosing Spondylitis in Korea

Objectives: The aim of this study was to determine the clinical profile of ankylosing spondylitis (AS) in Korea.

Methods: A total of 732 men and 98 women with AS were recruited for the cross-sectional component of the Hanyang University ankylosing spondylitis (HYAS) Study. All participants completed extensive questionnaires about their medical and personal histories, and two rheumatologists concomitantly performed clinical evaluation and previous medical record reviews for all participants.

Results: The mean age of onset (SD) was 20.9 (8.1) years. Three hundred and ninety-one patients (47.1%) were found to have a history of peripheral arthritis. Six hundred and four patients (73.9%) were found to have a history of hip joint involvement. Two hundred and thirty-six patients (28.7%) were found to be juvenile-onset AS (JoAS) patients. The frequency of uveitis differed between the sexes (28.2% of men vs 40.8% of women; p=0.03; OR: 1.63; 95% CI: 1.05-2.53). Peripheral arthritis (p<0.001; OR: 4.19; 95% CI: 2.98-5.88) and hip joint involvement (p<0.001; OR: 2.76; 95% CI; 1.77-4.29) were more frequent in JoAS group. HLA-B27 positive cases had a significantly younger age of symptom onset (by 5.3 years), more uveitis, and a higher frequency of hip joint involvement than HLA-B27 negative patients.

Conclusions: The clinical features of our patients are largely similar to those in other studies, with a few noticeable differences: 1) AS patients in Korea have a higher prevalence of peripheral arthritis and hip joint involvement; 2) female patients have more uveitis, and; 3) JoAS is common in our group.