“Our study suggests for the first time that vaccination against influenza may reduce the risk of venous thrombotic embolism (VTE),” said Dr. Joseph Emmerich, lead author of the study and professor of vascular medicine at the University Paris Descartes and head of the INSERM Lab 765, which investigates thrombosis.
“This protective effect was more pronounced before the age of 52 years,” he said while presenting the findings at the American Heart Association’s Scientific Sessions 2008.
VTE, the formation of a blood clot in a vein, is dangerous because the blood clot can break loose and travel through the circulatory system to the right side of the heart. It can further travel to the lungs, where it may prove to be life-threatening or even fatal.
For their research, the team conducted a case-control study among 1,454 age- and sex-matched patients (average age 52 years) from 11 centers in France (the FARIVE study).
The researchers compared 727 patients without personal history of cancer within the last five years who had initial episodes of VTE to a control group of age- and sex-matched patients free of venous and arterial thrombotic disease.
They revealed that patients younger than 18 years old — or those who already had VTE, had a diagnosis of active cancer or a history of malignancy less than five years previously, or had a short life expectancy due to other causes — were ineligible to participate in the study.