A new report released yesterday shows evidence of a reduction in blood clots for air passengers who received the flu vaccination. The so-called “economy class syndrome” can affect people travelling on long haul flights who have little leg room, and thus increase their chances of a blood clot developing.
The results of the research display a 26 per cent reduction rate of patients developing a venous thrombotic embolism (VTE) after receiving the injection. In addition, women taking the contraceptive pill had up to a 59 per cent less chance of developing the illness.
Deep vein thrombosis (DVT) is just one type of VTE - and clots usually form in the legs. However, if the clot gets into the blood stream and moves around the body, it could potentially reach the lungs, resulting in a possibly fatal pulmonary embolism.
The research, named the Faivre study, was carried out by a group of French scientists. A total of 727 VTE male and female patients took part in the study - all had no previous incidents of VTE and had an average age of 52.
Patients answered questions about their exposure to any VTE risk factors. Among these are pregnancy, use of the contraceptive Pill, hormone replacement therapy, recent injury or surgery, prolonged periods of immobilisation, or travel lasting more than five hours.
Participants then expressed whether they had received the flu jab within the last year. The results showed that on average, there was a 26 per cent less chance of developing a VTE for patients who had received the vaccination.
Risk was also reduced by 48 per cent for patients under 52, while women under the age of 51 who had received the jab had a 50 per cent risk reduction. Women on the Pill who had the injection were found to be 59 per cent less at risk.
The chance of developing either DVT or a pulmonary embolism were equally reduced by taking the influenza jab.
Yesterday scientists presented the results of their study at the American Heart Association’s Scientific Sessions meeting in New Orleans.
The study was headed by Dr Joseph Emmerich of the University Paris Descartes. On the findings he said, “Our study suggests for the first time that vaccination against influenza may reduce the risk of venous thrombotic embolism.”
The vascular medicine specialist added, “This protective effect was more pronounced before the age of 52 years.”
More research is needed to determine excactly why the flu jab has this protective effect. However one theory suggests the vaccine could prevent infection thickening the blood or reduce dangerous inflammation.
Dr Emmerich said, “Infections in general increase blood viscosity, and systemic inflammatory reactions to infectious agents can themselves trigger a thrombotic process,”
“However, influenza vaccination might lower the risk of thrombosis in other ways, as suggested by the even distribution of VTE events across the 12 months of the year in both vaccinated and unvaccinated cases in our study.”
Dr Emmerich suggested prescribing the flu injection for patients who had already suffered one VTE could be useful.