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Updated May 5, 2006

Economy Class Syndrome News


5/6/06 No newsPeople are still suffering disability and death from blood clots but it isn't news. David Bloom' death in Iraq was due to a misdiagnosed blood clot, but was forgotten after a few days.

7/15/04 Successful treatment Dr. Richard Chang at NIH announces succesful completion of his first DVT protocol dissolving clots with t-PA. He is opening a new protocol using a lower dose of thrombolytic agent that he believes will be even safer and still effective. Treatment is free but must commence within fourteen days of the formation of the clot. Call 1-800-411-1222 or Dr. Horne at 301-496-6891 or Dr. R. Chang at 301-402-0256.

12/20/03 Compression stockings didn't help four of nine people who developed DVT. Rodney Hughes et al followed up on 878 long-distance air travelers finding five cases of deep vein thrombosis and four pulmonary embolisms. People with risk factors such as recent injury or surgery were excluded. See our Research page.

10/4/03 National Alliance for Thrombosis and Thrombophilia, NATT, is organizing itself. Centers for Disease Control, CDC, brought victims and survivors of victims of thromboembolism together with experts and organizers such as Line Robillard, former head of the World Hemophilia Foundation. They are defining objectives and first-year goals and making plans to achieve those goals.

9/22/03 Pinokinase, a new pharmacologic compound, effectively prevents blood clots during air travel. Gianni Belcaro's latest study published 9/03 in Angiology found that, in two groups of air travelers considered to be at risk for blood clots, one group taking Pinokinase developed no clots. The other group developed clots at about the usual rate for these studies, about 5% developing clots larger than .5 cm, large enough to be harmful.

Both groups had been advised to flex their legs frequently but this and other studies are suggesting that leg flexing alone is not a reliable way to avoid clots. Both groups were also advised to drink plenty of water, about one cup per hour.

8/28/03 Centers for Disease Control hosted a meeting of people who can organize a sustained anti-thrombosis campaign. Included were people whose lives were changed by thrombosis, such as Kathy Earley, who lost her daughter Jessica. Also included is a support team of experts such as Line Robillard, who ran the World Hemophilia Foundation.

7/10/03 The Economist,a respected British journal, reports on a new study in the South African Medical Journal finding no clots detectable by ultrasound after long flights. However, elevated D-dimer levels, an indicator of clotting activity, were found in 10% of test subjects. This is consistent with a study by Rodney Hughes in New Zealand finding elevated D-dimer levels in 12% of test subjects.

6/28/03 The Lancet reports a study by Oxford University physiologists finding that coagulability does not rise in a hypobaric chamber simulating cabin altitude, contrary to several other studies.

4/7/03 David Bloom, 39, NBC reporter, dies in Iraq of pulmonary embolism: News reports say that he was complaining of calf pain for three days before his death. Anticoagulant treatment would have saved his life. We are looking for news whether, like many victims, he sought treatment unsuccessfully. One report says he was commuting weekly from the US to Iraq. If so, his flights are more likely the cause of the clot than his hours in the armored vehicle. Studies like Schobersberger's (below) show pro-clotting factors rising and anti-clotting factors falling during air travel, a dangerous combination.

4/2/03 UK Prosecution of Airline Executives: Investigators in the UK are preparing evidence for the Crown Prosecution Service to bring manslaughter charges for deaths of victims of economy class syndrome. Three cases are being investigated and eleven more expected shortly. Airline executives could face imprisonment and their companies unlimited fines. See 4/2 Independent story "Airlines may face charges over DVT deaths".

In the US, has asked for investigations by state attorneys general. US airlines are causing injury and death with statements asserting that blood clots are nothing to worry about. For example, Delta says: "These clots are not serious." (See Delta.) Certain state attorneys general are building files and/or committing to join if other states take action.

3/25/03 Wolfgang Schobersberger et al: A study of coagulation factors during a 9 hour flight found significant changes in blood chemistry. Coagulation involves a complicated interplay between factors that produce fibrin vs. factors that dissolve fibrin. In this study, Schobersberger et al found both increases in pro-clotting factors and decreases in anti-clotting factors. He found this in all of the test subjects, including 10 who were considered at moderate risk of clotting and 10 who had no known propensity for clotting. (See abstract at Thrombosis Research.) Dr. Schobersberger's research institute has been focusing on travel and liesure medicine and has published many studies on thromboembolism and related topics.

A previous study by Bendz found similar changes in blood chemistry in a hypobaric chamber with room to move about, showing that altitude, not immobility, was the cause of increased coagulability.

Dr. Schobersberger said: "Austrian Airlines supported the study by helping us in the logistics management (customs, equipment etc.). Moreover the last 3 rows of an airbus 330 were kept free for our study passengers and medical devices. Also Bichemie GmbH (producer of low molecular weight heparin Certoparin) supported our project." Austrian Airlines is the first airline to support a study of air travel thrombosis.

2/28/03 Washington: Congressional hearings: congressional staffers say that, with the support of the conferees from the CDC/APHA conference (below), congressional hearings are a possibility. In England, hearings in the House of Lords led to cooperation from UK airlines and most foreign airlines followed suit. Many of the conferees have signed a letter calling for congressional hearings. Others have said their organizations will sign after approval of their boards of directors.

2/26/03 Washington: APHS Survey - 99.5% unaware of economy class syndrome: In study released by the American Public Health Association 10 people in a group of 1,000 said they know what ECS is, but five of them said it relates to economic conditions. Only 5 were aware that it refers to blood clots caused by air travel.

2/26/03, Washington: DVT Conference: CDC and the American Public Health Association sponsored a conference in Washington today including 30 organizations such as the American Medical Association and the American Hospital Association , a who's who of public health organizations. Leading experts from Harvard, Mayo Clinic, and other institutions joined the group.

The main theme of the conference was that thromboembolism is a leading cause of death and it is largely preventable, mainly by increased awareness of how to avoid it. Several mentioned that the media's interest in economy class syndrome is the vehicle that should be used to increase public awareness.

The conference focused mainly on deaths caused by pulmonary embolism but thromboembolism also causes a substantial percentage of heart attacks and strokes. It also causes disability when DVT becomes chronic. Including these heart attacks and strokes, thromboembolism is far ahead of any other leading cause of death.

2/24/03 NIH study finds low-dose warfarin effective: A study released by the National Institutes of Health finds that, after initial warfarin treatment of three to six months, the dosage can be reduced for effective ongoing protection against recurrent DVT/PE. See

2/18/03 Leading causes of death: CDC's National Center for Health Statistics provides tables showing leading causes of death in age groups 20-24, 25-34, 35-44, and so on. But these tables don't list PE deaths separately; they are included as a subcategory of diseases of the heart. (Many more, according to Zamula and others, are erroneously reported as other forms of heart failure.)

To compare air travel thrombosis deaths with other leading causes of death in the 20-44 age groups, we counted the cases in's registry, finding that 47% are in the 20-44 range. If 100,000 deaths are caused by air travel and 47% are in the 20-44 age group, then there are 47,000 air travel thrombosis deaths in the 20-44 age range.

This makes air travel thrombosis the leading cause of death for people aged 20-44. Next highest is accidents with 34,540 victims. For all ages, air travel thrombosis is the fifth leading cause of death.

1/26/03 Athletic victims of air travel thrombosis: Executive Director Michael Reynolds presented a paper on athletic victims of air travel thrombosis at an International Angiology Union conference in Paris. Another speaker, Dr. Roland Questel, a member of the Olympic Committee , told of prevention methods that reduced the numbers of french Olympic athletes who suffered air thrombosis at the games in Sydney. Three UK athletes were victims.

1/9/03 WSJ - Don't drink the water : A November Wall Street Journal report found SERIOUS contamination of airline tank water, the water flowing from taps in the galley and in the lavatory. No airline had drinkable tap water. Water offered for drinking usually is bottled water, but sometimes they run out of it.

Mixing electrolytic beverages from powder is a way to avoid extra weight and bulk in carry-on luggage, but using airline tap water would be a serious mistake. And if you look for electrolytic beverages in other countries, mixable powder may be all you can find. director Michael Reynolds was unable to find Gatorade anywhere in Paris, including Decathlon, a big store catering to runners. In their Hydration section he found powders such as Isostar for mixing isotonic drinks.

He said: "To avoid carrying any more bottled water than necessary, I mixed bottled water and Isostar in an empty 20 oz wide mouth bottle, refilling it with bottled water in the galley. The airline, US Airways, had no objection to refilling the 20 oz bottle, but when I asked if I could take a one of their full bottles they said no, if they gave me a full bottle then 180 other people would also want one. I kept an extra 20 ounces of bottled water in reserve in a carry-on bag in case the airline ran out of bottled water."

1/8/03 Electrolytic beverage : Experts recommend drinking non-caffeine non-alcoholic beverages to avoid increased blood viscosity during air travel. In a recent study, test subjects taking a nine hour flight were divided in two groups, one drinking water and the other drinking an equal amount of an electrolytic beverage. The people drinking water developed significant increases in blood viscosity (thickness) and urine output. The people drinking the electrolytic beverage did not. sent this study to several experts who agreed that an electrolytic beverage is apparently a much better choice than water during air travel. See Hamada in Bibliography.

11/21/02 Galveston : In Blansett v. Continental Airlines, Judge Kent rules that Shawn Blansett's stroke suffered aboard a Continental flight to London was an accident as defined by the Warsaw Convention.

10/24/02 Dr. John Marx, Altitude Induced Venous Failure :

New research suggests that the main cause of air travel thrombosis is the low cabin air pressure. Previously Bjorne Bendz in Norway found coagulation factors rising, hour by hour, at cabin altitude and Gianni Belcaro in Italy found clots forming in about four percent of air travelers. Now Dr. John Marx at the Ashley clinic in Melbourne has measured venous failure in the lower legs caused by cabin altitude.

The veins return blood to the heart. In cases of poorly functioning veins, a standard treatment is to increase tissue pressure using compression stockings. Studies show that a compression stocking rated at 20 mmHg (twenty millimeters of mercury) doubles the venous return of blood from the leg to the heart. Dr. Marx wondered if reducing pressure has the opposite effect, reducing venous return. If so, the effect on air travelers could be profoundly harmful. In the first eight minutes of a jetliner's climb, cabin pressure drops from about 760 mmHg to about 560 mm, a difference of 200 mm, an effect ten times greater than that of a 20 mm compression stocking and in the opposite direction.

Using photoplethysmography, a standard technique for evaluating venous function, Dr. Marx took measurements while ascending a mountain with air pressure at the top about equal to cabin altitude. At the alpine village of Thredbo, altitude 1,380 meters, venous blood flow had fallen by about fifty percent. At the top of the mountain (2228 meters), venous blood flow had been further reduced to only thirty percent of normal. "Our subjects were tipped into severe venous failure," he says, suggesting that "All plane passengers will be in a state of hypobaric venous stasis" at cabin altitude. (Stasis is stagnant blood subject to clotting. Hypobaric means reduced barometric pressure.)

Compounding the effect of stasis is the movement of fluids from central circulation to the periphery causing the swelling that, for some people, makes it hard to get their shoes back on after the plane lands. The reduced venous return is unable to cope with the arterial inflow, and the result is a gradual accumulation of fluid in the peripheral tissues. Fluids escaping the capillaries leave behind blood cells and molecules too large to pass through capillary walls. The blood becomes thicker and more prone to clotting. The gradual movement of fluids correlates with Bendz' finding of hour by hour increases in coagulation factors and with Hamada's finding of increased viscosity of the blood in the lower leg.

Dr. Marx' study, titled "Altitude Induced Venous Failure," is being submitted to the Australasian Phlebology Journal for publication. He plans further tests in January '03. If the results are consistent with the initial study, it will explain why studies by Scurr and Belcaro found no clots in people wearing compression stockings. It will also explain why people in the front of the aircraft are just as likely to suffer clots as people in economy class. (Previously clots were thought to be caused by cramped seating in the rear.)

10/22/02, London, Daily Mail: Sixteen families of deceased victims of air travel thrombosis are calling for criminal prosecution of airline CEOs. The airlines named include American, Airtours, British Airways, Canadian, Emirates, JMC, Qantas, Singapore and Virgin. Roger Wiltshire, of the British Air Transport Association, said the industry had started advising passengers on avoiding DVT well before the Health Department's guidance was issued. Any charges would be vigorously defended, he added.

10/16/02 New anticlotting drug: An experimental blood-thinning drug, ximelagatran, (Xanta) developed by AstraZeneca Plc. is being tested for prevention of clots after surgery. In a trial involving 680 knee surgery patients in 74 hospitals, Xanta was substantially more effective than warfarin: 19% of the Xanta patients developed clots vs. 26% of the warfarin patients. See Annals of Internal Medicine, 10/15/02.

Xanta is much easier to use than warfarin or heparin. It is given in a pill in fixed doses, is rapidly absorbed, and does not require blood tests to make sure it is at a safe and effective level. It could become a safe and effective prophylactic for air travel thrombosis. Another drug, Plavix (clopidogrel bisulfate), has similar efficacy and ease of use.

9/27/02 Heart Attack: Rebecca Yates, 22, died of cardiac arrest after a flight to Las Vegas from Brisbane. Doctors say an artery was blocked by a blood clot developed during her flight.

6/26/02 Dr. Richard Chang: of National Institutes of Health, is offering free clot-dissolving treatment using recombinant tissue plasminogen activator, rt-PA. The standard treatment for DVT is three to six months on warfarin, a blood thinner which does not dissolve clots but protects the victim against additional clots while a natural process called lysing dissolves the DVT. However, permanent damage often occurs in the vein by the time the clot has naturally dissolved. In about 30 percent of victims, chronic phlebitis develops later, resulting in disabling swelling and pain in the leg. With Dr. Chang's treatment, clots are dissolved before the permanent vein damage occurs.

Dr. Chang is offering free rt-PA treatment to DVT victims but only if they can reach him within two weeks of the formation of the clot. After that, clots resist rt-PA treatment. This two-week limit is a catch-22 for most victims of air travel thrombosis because they typically spend more than two weeks wondering what is wrong and/or receiving incorrect diagnoses.

5/23/02 Soccer teams: The English and Irish soccer teams flying to the World Cup games in Japan broke the trip into two segments with a two-day stopover in the middle. They also wore compression stockings.

5/9/02 DVT after three hour flight.: A few days ago a young man reported suffering a DVT after a three hour flight from to Orlando from San Juan, where he had run a marathon. Today we heard from Jay Gordon, who nearly died from PE in both lungs after a three hour flight from Moline to Pheonix. Graham was in excellent health, walking three miles aerobically three times per week.

5/7/02 Aerospace medical association: At an annual meeting in Montreal, Dr. Michael Bagshaw, medical director for British Airways, was the main speaker on the subject of air travel thrombosis. He apologized for having nothing new to report. Apparently he was unaware of the largest and most recent study, Belcaro's work with 1,900 subjects finding DVT in 5% of air travelers.

One of the questions following Bagshaw's presentation was: "Why do we keep advising that people with risk factors should consult their physician, while the physician probably has no idea what to recommend?" Bagshaw's response was that a mailing had been sent to physicians. The mailing was in the UK. In the rest of the world, physicians remain generally unaware of air travel thrombosis.

4/16/02: Bo Eklof wants to work toward publishing our data on athletic victims of air travel thrombosis. He wants to ". . really get the scientific community as well as the public aware of the problem." He said he was criticized at the conference in New York that too many physicians and the majority of the public are still unaware of this problem. Meanwhile in the New York Times, Mike Wascom, spokesman for the Air Transport Association, says "I think we have done more than enough to properly inform the traveling public."

4/11/02 New risk of heart attack and stroke: At the World Congress of the International Angiology Union in New York a session on air travel was chaired by Bo Eklof, MD, one of the best-known US experts. Unlike other sessions, this one was standing room only, indicating intense interest.

Dr. Omer Iqbal of Loyola University pointed out that it is a mistake to focus only on venous clotting. Dr. Iqbal warns that when coagulability rises during air travel, the risk of arterial clotting also rises, leading to heart attacks and strokes. Heart attacks and strokes during air travel were thought to be coincidental. Now it is clear that some of them are actually caused by air travel.

People being treated for atrial fibrillation are often instructed to take warfarin because of the risk of clotting and stroke. Air travel aggravates this risk. A study in Norway found increased coagulability in all of the subjects tested at simulated cabin altitude. Dr. Iqbal warns that people being treated for atherosclerosis, diabetic arteriopathy, and microangiopathic disorders are all at increased risk. (An excerpt from Dr. Iqbal's abstract is on our Research page.)

3/15/02 Another bad week:This week we posted messages regarding a young bride and a young groom (not related) who died of pulmonary embolisms after their wedding trips. The count of athletic victims of flight-induced DVT is now at 56 and still ten times higher than the number associated with any other risk factor for DVT, such as a family history of DVT.

2/28/02 IATA Conferences: A physician working as a consultant to the International Air Transport Assn. called He wanted us to know how sincere and dedicated the airline medical directors are and how much they want to do the right thing about economy class syndrome. He said they have conferences to discuss what should be done. I asked if I could attend the next conference. "They're not really for lay people," he said, "at the last conference, three of the speakers were attorneys."

1/31/02 230 Victims Sue Airlines. In England the suit of 286 victims against 30 airlines has been certified as a class action. The headline says 230 while the body of the story says 286, suggesting that the number of claimants is rapidly rising, as it did in Australia. see

12/24/01 Diver, 28 dies of flight-induced DVT .. More examples of a healthy young women falling victim. The diver was with her father, who thought he was more at risk and was wearing compression stockings. see The story also says that Scotland's leading woman squash player, Pamela Nimmo, 23, was diagnosed as suffering from pulmonary embolisms or blood clots to the lungs in February, a month after making a ten-hour flight. In June, Shirley Henderson, 46, from Carluke, Lanarkshire, died with a DVT while on a long-haul flight.

11/30/01 UK Department of Health issues Advice on Travel-Related Thrombosis. This report tries to avoid saying anything that anyone might disagree with. For example: "There is some evidence that long-haul flights, especially when passengers have little or no exercise, may increase the risk of developing DVT. The number of victims is unknown, but experts say it is small. Also, it is not easy to decide whether the flight itself caused the DVT/PE or whether these people were at risk for other reasons (over 40, family DVT history, etc). This is because DVT and PE are relatively common conditions anyway and more people than ever now travel by air every year."

You can see the full text of the Department of Health advisory at

On the 30th BBC was saying, at half-hour intervals, that people with risk factors should consult their doctor, again ignoring the fact that most victims do not have any risk factors. The BBC story is at

11/15/01 Still More Bad News. A man, 33, dies of PE after a flight to Paris. He thought he was safe because he exercised his legs at two-hour intervals.

10/15/01 More Bad News. Recent messages raise a new level of urgency.

1. A woman suffered a DVT on a two-hour flight from England to Spain. Previously it was thought that there is no danger in flights of less than four hours. She had to make the return trip by surface transportation, including a ferry.

2. An additional DVT developed in a woman being treated with warfarin for flight-induced DVT. Doctors concluded that she is resistant to warfarin and now she is taking daily heparin shots.

3. A healthy physician is stricken with multiple pulmonary embolisms and nearly dies after a flight from Arkansas to Idaho. If this can happen to a healthy physician, no one is safe.

9/20/01 New England Journal of Medicine A study of 56 victims of pulmonary embolism at Charles de Gaulle Airport found a direct correlation between the distance traveled and the likelihood of PE.

9/19/01 Bad News See 9/19 Susan on the Message page. She had no risk factors, flexed her feet at 30 minute intervals, but also slept and suffered a massive DVT injury which has become chronic. She has been told she will have to take warfarin for life.

This puts a new level of urgency on the need to tell people what they need to know. Susan's injury could have been treated before it became chronic if someone had told her what symptoms to watch for. Should this be put off while the airlines focus on security? The number of people whose lives are ruined or ended every single day by flight-induced DVT is greater than the number of people on board all four of the hijacked airliners.

9/11/01 Large Study in New Zealand A study is beginning in New Zealand which apparently would be similar to Scurr's study but about five times larger. Scurr did ultrasound scans of air travelers before and after their vacation flights and found that 10% developed blood clots. The New Zealand study is described at .

9/5/0148 Hours This CBS News program included two segments on flight-induced DVT, one focusing on Karen Perkins, the woman who died in the water off Belize. The second segment featured Bo Eklof of the John Burns School of Medicine at the University of Hawaii. He has done several studies of flight-induced DVT published in medical journals. On CBS he appears simply as a physician who sees a lot of DVT victims arriving in Hawaii.

8/25/01 Away on Business, Mike Conlon (Reuters) Conlon says is the most comprehensive source of expert and anecdotal information about flight-induced DVT. His column appears in many newspapers, such as the St. Louis Post-Dispatch.

7/29/01 The Observer, Airlines to be Sued Over DVT Deaths, Mark Townsend. Watford-based Collins Solicitors - experts in transport litigation - have launched proceedings against airlines on behalf of 30 British air passengers, 10 of whom died, and are confident of success. These cases were carefully selected to have the best chance of success. If successful, many more will follow. See,3858,4230225,00.html

7/22/01 "No Evidence . . . " Michael Wascom, spokesman for the Air Transport Association, says "The overwhelming body of medical evidence" supports ATA's position that air travel does not cause blood clots. In fact, he has only one discredited study to back him up. This study was so badly flawed that it concluded that recent injury reduces the risk of blood clots. This is like saying that having a few drinks reduces the risk of auto accident. All of the credible scientific studies say that air travel causes blood clots.

Older news items:
News items through June 2001