Systemic lupus erythematosus in an adult population in southern Sweden: incidence, prevalence and validity of ARA revised classification criteria.

In a defined Swedish population an annual incidence of 4.8 cases, a mortality of 1.3 cases and a prevalence of 39 cases per 100 000 individuals was found for systemic lupus erythematosus. Sensitivities were comparable (94%, cf. 92%) for ARA criteria of 1982 and those of 1971. Males had more internal organ criteria and showed a tendency to fewer cutaneous criteria than females. Spontaneous abortion was rare and hospitalization infrequent among the 65 patients studied.