A Comparative Family Study of Rheumatoid Arthritis and Systemic Lupus Erythematosus

Abstract

CONFLICTING results have been reported recently on the occurrence of serologic and physical abnormalities in families with a case of collagen disease. Most reports in the past fifteen years have described a high frequency of arthritic and serologic abnormalities characteristic of the collagen diseases among relatives of patients with rheumatoid arthritis or systemic lupus erythematosus.^{1 , 2} In a few reports on systemic lupus erythematosus, however, the increase above normal expectancy was not marked.^{3 , 4} And in some recent studies on rheumatoid arthritis no evidence of a familial aggregation of the disease was reported.^{5 6 7} These variations in results reflect differences in study design . . .