Factors other than immobility, such as lower air pressure and oxygen levels, may contribute to the development of potentially fatal blood clots during air travel, according to new findings by researchers from the Netherlands (Schreijer AJM et al. Lancet. 2006;367:832-838).
Studies indicate that air travelers have a 2-fold to 4-fold increased risk of deep vein thrombosis (DVT), with higher risks after longer flights compared with shorter ones. To investigate whether factors other than immobility might play a role in increasing DVT risk, researchers from Leiden University Hospital in the Netherlands measured the concentration of markers for clotting activation in the blood of 71 volunteers before, during, and immediately after an 8-hour flight. The same individuals also participated in two control exposure scenarios, sitting for 8 hours in a movie theater and engaging in 8 hours of regular daily activities.
Stephenson J. Air Travel and DVTs. JAMA. 2006;295(15):1763. doi:10.1001/jama.295.15.1763-b