Prevalence and clinical characteristics of ankylosing spondylitis in Iceland - a nationwide study

• Main Authors: Geirsson, Arni Jon, Eyjolfsdottir, Helga, Bjornsdottir, Gyda, Kristjansson, Kristleifur, Gudbjornsson, Bjorn
• Other Authors: Department of Rheumatology, The National Hospital of Iceland, Reykjavik, Iceland.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Clinical And Experimental Rheumatology S.A.S 2011
• Subjects: Adolescent; Adult; Age of Onset; European Continental Ancestry Group; Female; HLA-B27 Antigen; Humans; Iceland; Incidence; Male; Prevalence; Questionnaires; Severity of Illness Index; Spondylitis; Ankylosing; Young Adult
• Online Access: http://hdl.handle.net/2336/118907

To access publisher full text version of this article. Please click on the hyperlink in Additional Links field OBJECTIVES: To determine the prevalence and clinical characteristics of ankylosing spondylitis (AS) in the Icelandic population, which carries a high prevalence of HLA-B27. METHODS: A nationwide search was performed by screening hospital records and private rheumatology services for cases of AS in association with an on-going genetic study. Individuals diagnosed with AS according to the modified New York criteria were asked to participate in the study by answering a standardised questionnaire and to undergo an interview and clinical evaluation. RESULTS: A total of 256 individuals fulfilled the modified New York classification criteria for AS (169 male, 87 female); 84% of these individuals were HLA-B27 positive vs. 15% in the population (p<10-16). Of those contacted 223 patients (87.1%) answered the standardised questionnaire and were included in the study. The prevalence of AS in Iceland was 0.13% (CI 0.11-0.14%). A highly conservative prevalence number, based only on clinically evaluated patients, gave prevalence of 0.10% (CI 0.09-0.11%). Mean age at onset of symptoms was 24+/-8 years and at diagnosis 32.1+/-10.2 for male and 34.2+/-10.1 for female patients (not significant). Female patients more often had arthritis in peripheral joints and male patients were more often diagnosed with iritis. Prostatitis was experienced by 27% of male patients. CONCLUSIONS: AS is less common in the Icelandic population than reported in various Caucasian populations with a similar prevalence of HLA-B27.