Population Studies of Rheumatic Diseases on a Coastal Island: PART II. ANTINUCLEAR FACTORS AND ANTITHYROID ANTIBODIES

Abstract

In 1951 and 1961 the population (about 500 persons over 15 years of age) of a small island (Schiermonnikoog) was investigated for the presence of rheumatic disease. About 25% of those investigated had been born on the island. The results of the 2 surveys were about the same. About 25% complained of rheumatism, and of these about 6% had rheumatoid arthritis, about 50% had osteo-arthritis, and about 44% had non-articular rheumatism. In 1961 2.27% of the population had a positive Waaler-Rose and/or latex-fixation test, and 1.8% were "false-positives". Positive serological reactions were not more common in relatives up to the third generation of patients with rheumatoid arthritis or of "false-positive" cases. Rheumatoid arthritis and "false-positive" reactions were not more frequent in that part of the population that could be regarded as autochthonous. Tests for anti-nuclear factor and antithyroid antibodies gave a number of positive reactions, but there was no correlation between the immunofluorescent technique, the Coombs" consumption test, and Boyden''s passive haemagglutination technique, or between the presence of antibodies and the diagnosis of clinical rheumatic disease. No patients with systemic lupus erythema-tosus or Hashimoto''s disease were found in the island.