Autoimmune diseases and risk of pulmonary embolism

1have obtained data from the MigMed2 database (constructed from sev eral national Swedish data registers) and report analyses to show that pulmonary embolism is a serious problem in patients with autoimmune disease. The investigators’ conclusion that autoimmune disorders should be re garded as hypercoagulable is well validated in their study. The data sources used in the accompanying article are very reliable because they contain information about all registered residents of Sweden. A personal identifi cation number identifi es every individual in the country and allows the databases and registers to track medical events in their lives. This aspect is a boon for researchers trying to identify diff erent risk factors for diseases with great reliability. Zoller and colleagues’ results are therefore able to show that autoimmune disorders are clearly associated with risk of pulmonary embolism, especially in the fi rst year after hospital admission. Venous thromboembolism (deep vein thrombosis and pulmonary embolism) has a high mortality and is a common complication during hospital admission. Pulmonary embolism accounts for 5–10% of deaths in patients admitted to hospital.