Prevalence of rheumatoid arthritis in circumpolar native populations.

Objective: To compare the prevalence of rheumatoid arthritis (RA) in related, but geographically separate, indigenous circumpolar populations.

Methods: Cases were identified by community survey in Russia and by examination of cases located through arthritis registries, a computerized patient information database, and query of local health care providers in Alaska. All possible cases were verified by examination and application of the American College of Rheumatology 1987 criteria.

Spondylarthropathic diseases in indigenous circumpolar populations of Russia and Alaska.

Aims: To compare the nature and frequency of spondylarthropathy in geographically separated but genetically related populations with a high prevalence of HLA-B27.

Methods: Using a common questionnaire and disease criteria, cases were ascertained through cross-sectional community surveys in Russia and by examination and study of possible cases identified through rheumatic disease registries and the Native Health Service's computerized patient care data system in Alaska.

Results: Similar overall prevalences of spondyloarthropathy (2.

Spondyloarthropathies in circumpolar populations: II. Characterization of the populations.

For epidemiologic studies of spondyloarthropathy in circumpolar peoples of Chukotka, Russia and Alaska, we gathered demographic, physical and laboratory data to provide a background for evaluating and comparing factors that may influence susceptibility and clinical expression of disease. The study groups included the Chukchi and Siberian Eskimo of Russia and the Inupiat and Yupik Eskimo of Alaska. The 4 groups were remarkably similar in population structure, educational attainment, mean hemoglobin concentrations and frequency of the Class I histocompatibility antigen HLAB27.

Spondyloarthropathies in circumpolar populations: I. Design and methods of United States and Russian studies.

Parallel epidemiologic studies of spondyloarthropathy in aboriginal circumpolar populations were carried out by U.S. and Russian investigators.

HLA class II and HLA-B27 oligotyping in two Siberian native population groups.

It was the purpose of this study to better define the frequency of HLA-B27 subtypes and HLA class II alleles among indigenous populations from the eastern tip of the Chukotka Peninsula of Siberia, Russia, which have higher frequencies of HLA-B27 (40%) and spondyloarthropathies (2%) than Caucasian populations and test the hypothesis that these populations are more closely related to Orientals. Siberian Eskimos and Chukchi residing in four coastal villages on the Chukotka Peninsula inhabited by Siberian Eskimos and Chukchi people were examined using oligotyping of the polymerase-chain reaction-amplified second and third exons of the HLA-B27 gene. HLA-class II alleles (DRB1, DQA1 and DQB1) were similarly determined.

"Cross-sectional" study of low back pain among workers at an industrial enterprise in Russia.

Study Design: A representative sample of 18- to 65-year-old workers from a machine-building factory was studied using a standardized questionnaire.

Objectives: To study the prevalence of low back pain syndrome among workers at an industrial enterprise and to estimate the association between low back pain syndrome and certain factors.

Methods: This was a cross-sectional study of 800 workers (400 men and 400 women), who were invited to participate in the study.

HLA-B27 subtypes among the Chukotka Native groups.

The purpose of this study was to assess the relative frequency of the known HLA-B27 subtypes in HLA-B27 positive Chukotka natives, which have higher frequencies of HLA-B27 (to 40%) and spondyloarthropathies (to 2%) than the Russian Caucasian population. Using oligotyping of the polymerase-chain reaction amplified second and third exons of the HLA-B27 gene in 86 DNA samples from HLA-B27 positive individuals were successfully typed. All had HLA-B*2705, including 4 patients with Reiter's syndrome and 5 with ankylosing spondyloarthritis, except one Eskimo who had HLA-B*2702.

Prevalence of spondyloarthropathies and HLA-B27 in the native population of Chukotka, Russia.

Objective: We sought to determine the prevalence and nature of spondyloarthropathies (SPA) and the prevalence of HLA-B27 in the native selected circumpolar population of Chukotka, Russia.

Methods: We conducted a cross sectional study that included medical examinations and interviews of 355 of 498 (71.3%) native residents of 2 Eastern Chukotka settlements, Enmelen and Nunligran.

Spondyloarthropathies in circumpolar populations of Chukotka (Eskimos and Chukchi): epidemiology and clinical characteristics.

Objective: We sought to determine the prevalence of HLA-B27 and the prevalence and nature of spondyloarthropathies in the native residents of Eastern Chukotka, Siberia, Russia.

Methods: We conducted a cross sectional study with medical examination and interview of 464 of 640 (72.5%) native residents of 2 Eastern Chukotka settlements, Sireniki and Novo-Chaplino.