Antiphospholipid syndrome: clinical and immunologic manifestations and patterns of disease expression in a cohort of 1,000 patients.

Objective: To analyze the clinical and immunologic manifestations of antiphospholipid syndrome (APS) in a large cohort of patients and to define patterns of disease expression.

Methods: The clinical and serologic features of APS (Sapporo preliminary criteria) in 1,000 patients from 13 European countries were analyzed using a computerized database.

Results: The cohort consisted of 820 female patients (82.