Autoantibodies of systemic rheumatic diseases in the healthy elderly.

Antinuclear antibodies, anticardiolipin antibodies and IgM rheumatoid factor were determined in 300 healthy aged subjects, comparing their prevalence to that in 100 healthy subjects aged between 19 and 44 years and 352 patients under 65 years of age, affected by various systemic rheumatic diseases. Increased production of IgM rheumatoid factor and antinuclear and anticardiolipin antibodies was found as characteristic of aged humans, and suggested that a correction for age should be considered in evaluating the clinical significance of autoantibody profiles in elderly patients.