List of Flight Health Risks is Growing

An aging population increasingly must consider whether getting on a plane is a wise health decision.

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Add health risks to the list of concerns that plague commercial air travel these days. We've been worried about paying for a piece of checked luggage or getting chiseled on a meager snack. But it turns out the medical and scientific community sees an airline cabin as a big petri dish -- and one that carries many threats.

[ See America's Best Healthy Places to Retire.] Consider this chilling summation in a recent medical journal piece by physicians Danielle Silverman and Mark Gendreau:

Almost 2 billion people travel aboard commercial airlines every year. Health-care providers and travellers need to be aware of the potential health risks associated with air travel. Environmental and physiological changes that occur during routine commercial flights lead to mild hypoxia and gas expansion, which can exacerbate chronic medical conditions or incite acute in-flight medical events. The association between venousthromboembolism [potentially lethal blood clots] and long-haul flights, cosmic-radiation exposure, jet lag, and cabin-air quality are growing health-care issues associated with air travel. In-flight medical events are increasingly frequent because a growing number of individuals with pre-existing medical conditions travel by air.

No wonder John Madden takes the bus!

Older travelers who fly frequently are at greatest risk here, especially if they take longer flights. And if they have pre-existing medical conditions, it makes sense for them to make an appointment with their doctor before booking a flight.

[See 9 Health Tips for Overseas Travel.]

In the case of life-threatening blood clots, for example, there is an emerging consensus that flying on an airplane can double or triple your health risks. And while the likelihood of an event remains small, untreated clots are so often fatal that even a small number is not to be ignored. What's a traveler to do? Drink lots of water, cut back on alcohol and caffeine, move around frequently during the flight, do calf-muscle exercises and, if you're not the most nimble goat in the herd, wear compression stockings. Here's a set of more formal tips assembled by Drs. Silverman and Gendreau , who reviewed the body of existing air flight health research in a recent Lancet article, "Medical issues associated with commercial flights":

Low risk: Flight time less than 8 hours or distance less than 5000 kilometers. Recommendations: Avoid constrictive clothing around waist and lower extremities; avoid dehydration; move about cabin several times or do calf-stretching exercises.

Moderate risk: Flight time more than 8 hours or distance more than 5000 kilometers, plus obesity, large varicose veins, pregnancy, hormone-replacement therapy, tobacco use or oral contraceptives, or relative immobility. Recommendations: Low-risk measures plus wear properly fitted below-knee compression stockings and aisle seating.

High risk: Flight time more than 8 hours or distance more than 5000 kilometers plus history of previous venous thromboembolism; hypercoagulable state, major surgery six weeks before air travel (including hip or knee arthroplasty), known malignancy. Recommendations: Moderate-risk measures plus low-molecular-weight heparin injected before departure in individuals who are not on warfarin.

Newer aircraft tend to have better air-filtration and circulation systems but not to the point of providing enhanced passenger protection against airborne illnesses. The article says the science has yet to be done about the specific impact that grounding planes would have on the spread of a pandemic. But it notes that one study "showed that the peak date of the U.S. influenza season was delayed 13 days after the terrorist attacks of Sept. 11, 2001, consistent with a greatly reduced number of flights during that period."

While cosmic radiation is not a health risk for general travelers, it can pose problems for airline crew members and especially for frequent fliers who are pregnant. Is there any good news here? Yep. We're getting closer to effective treatments for jet lag. Taking the hormone melatonin, research indicates, has become "the gold standard treatment for jet-lag symptoms."