PREVALENCE OF SPONDYLOARTHROPATHIES IN ALASKAN ESKIMOS

Objective. To estimate the prevalence of spondyloarthropathies (SpA) i n 2 Alaskan Eskimo populations, using improved methodology for case as certainment and new, more inclusive classification criteria. Methods, Through existing rheumatic disease registries, health care providers a nd the Alaska Area Native Health Service (AANHS) computerized patient information system, we identified ail native residents of the 2 study regions with a diagnosis of any inflammatory arthritis or problems cha racteristic of SpA, such as iritis or persistent back pain. Individual s with such diagnoses or problems were evaluated in clinic, according to a standardized protocol (interview, examination), and by medical re cord review, pelvic radiography and laboratory tests. Each case was ev aluated according to standard diagnostic criteria for the individual d isease entities and by the Amor and European Spondylarthropathy Study Group (ESSG) preliminary classification criteria for SpA. Results. We identified 104 cases of SpA in the combined Eskimo populations, an ove rall prevalence of 2.5% in adults aged 20 and over. Both undifferentia ted (USpA) and reactive SpA were more common than ankylosing spondylit is (AS). Conclusion, Using the new criteria and a more effective appro ach to case ascertainment we found the prevalence of SpA to be about t wice that found in our earlier studies of adult Eskimo populations. Th e prevalence of SpA was very similar in men and women. Despite the kno wn high prevalence (25-40 %) of HLA-B27 in the study populations we di d not find the prevalence of any form of SpA to be as strikingly high as that of AS (6-10%) for the Canadian Haida.