New Pulmonary Embolism Risks - Why?

Autoimmune disorders are linked to an increased risk for pulmonary embolism

/ Author:  / Reviewed by: Joseph V. Madia, MD

(RxWiki News) Blood clots affect many parts of your body, including your lungs. A new study shows that autoimmune disorders increase the risk of blood clots, which in turn, increases the risk of a pulmonary embolism.

A study examining hospital admissions discovered a link between autoimmune disorders and an increase in pulmonary embolism hospitalization within a year. Autoimmune disorders were linked to a six-fold increase in the risk to be hospitalized for a pulmonary embolism. Researchers believe that this could warrant preventative medical treatment.

"Ask your doctor about symptoms of blood clots if you have an autoimmune disorder."

Autoimmune disorders affect the normal behavior of the immune system, causing it to attack healthy tissue. These disorders include psoriasis, Crohn's disease, chronic rheumatic heart disease and Graves' disease (which affects the thyroid). Autoimmune disorders cause inflammation, which is linked to venous thromboembolism, or blood clots.

The study examined 500,000 patients admitted to a hospital due to one of 33 types of autoimmune diseases from 1964 until 2008. The research led by Dr. Bengt Zöller, Center for Primary Health Care Research, Lund University and Clinical Research Centre, Malmo University Hospital in Sweden, discovered that all 33 types of autoimmune diseases were linked to an increased risk in pulmonary embolism hospitalization within a year.

The total risk of a pulmonary embolism within a year was six times higher for patients hospitalized with an autoimmune disorder compared to patients without an autoimmune disorder. Dermatomyositis, a muscular disease whose symptoms include inflammation and a skin rash, was associated with a 16-fold increase in the risk of a pulmonary embolism.

The risk of a pulmonary embolism was 50 percent higher after one year and slowly goes down to 15 percent after five years and down to four percent after 10 years.

The study notes that while autoimmune disorders increase the risk of blood clots, there are different reasons in each autoimmune disorder that cause the increased risk. Researchers concluded that autoimmune disorders should be considered blood clotting disorders as well as inflammatory disorders.

In an additional comment, future studies can help identify inflammation indicators for pulmonary embolism according to Dr. Carani B. Sanjeevi, Karolinska Institutet and Karolinska University Hospital, Stockholm, Sweden. 

Researchers recommended prophylaxis, or preventative treatments, for patients with autoimmune disorders. Dr. Sanjeevi also recommends possible treatment involving anti-inflammatory drugs as well as preventative treatments for blood clots. Future research can focus on which autoimmune disorders need preventative treatment for pulmonary embolism and which disorders best respond to preventative treatment.

This study was published in the November edition of The Lancet.

Reviewed by: 
Review Date: 
November 29, 2011
Last Updated:
December 1, 2011