Posted - January 31, 2010

Venous Clotting and Obesity

Your risk of deep vein thrombosis and pulmonary embolism increases with obesity, but researches have discovered that your gender and the location of the excess weight are also important factors.

In a study posted online in Circulation: Journal of the American Heart Association, Dr. Marianne Tang Severinsen of Aarhus University Hospital noted that the distribution of body fat has an important impact on venous clotting and arterial thrombotic risk.

For men, an increase in waist circumference of 5 centimeters was associated with an increase in risk of venous thromboembolism of up to 18 percent, but for women, that risk rose up to 21 percent for an increase in hip size instead.

The researchers studied results from a “Diet, Cancer and Health” study of almost 60,000 mean and women. Following up 10 years later, there were 641 venous thromboembolic events that occurred. Whether they were deep vein thrombosis or pulmonary embolism, these events were less affected by known risk factors, such as prolonged travel, than they were by increased body size and circumference.

Dr. Severinsen and her team found that with obese patients, a diagnosis of venous thromboembolism can be more challenging, because obesity can underestimate the effects.

While the complete biological link to venous thromboembolism remains unknown, the researchers have speculated that fat secretes substances that contain procoagulant activity.