Contrast between Epidemiological and Clinical Concepts of Rheumatoid Arthritis

Abstract

The synovial membrane and the joints can react to disease in only a few ways. The histological picture of synovitis is very similar in most inflammatory joint diseases, and the clinical signs of arthritis are only occasionally specific for a certain disease. In addition, the clinical picture of diseases may vary widely. Thus the clinical picture of various inflammatory joint diseases is overlapping, and the specificity of clinical diagnostic criteria is poor. A cross-sectional study of a population will always reveal cases with polyarthritis meeting the clinical criteria of rheumatoid arthritis (RA), but never developing chronic disability. These cases have usally been classified as RA in epidemiological studies.