Prevalence and clinical characteristics of ankylosing spondylitis in Iceland - a nationwide study
A.J. Geirsson, H. Eyjolfsdottir, G. Bjornsdottir, K. Kristjansson, B. Gudbjornsson
2010 Vol.28, N°3
PI 0333, PF 0340
Free to view
(click on article PDF icon to read the article)
PMID: 20406616 [PubMed]
Accepted : 10/12/2009
In Press: 23/06/2010
To determine the prevalence and clinical characteristics of ankylosing spondylitis (AS) in the Icelandic population, which carries a high prevalence of HLA-B27.
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.
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.
AS is less common in the Icelandic population than reported in various Caucasian populations with a similar prevalence of HLA-B27.