Flight attendants get cancer more than the general population, ‘striking’ new study shows
Higher prevalence of every type of cancer examined found in flight crew, despite their low rates of overweight and smoking, Harvard research finds. Also in health news, the ‘holy grail’ of an insulin pill for diabetics is a little closer
Flight crews have higher than average rates of some cancers, according to a study of more than 5,000 US-based flight attendants.
“We report a higher lifetime prevalence of breast, melanoma and non-melanoma skin cancers among flight crews relative to the general population,” said Irina Mordukhovich, a researcher at the Harvard TH Chan School of Public Health and co-author of a study published in the journal Environmental Health.
“This is striking given the low rates of overweight and smoking in this occupational group,” she said.
Just over 15 per cent of the 5,366 flight attendants who took part in the study reported ever having been diagnosed with cancer. The study found a higher prevalence of cancer in flight crew for every type of cancer examined, even taking age into account.
About 3.4 per cent of the women who flew for a living had breast cancer, compared to 2.3 per cent in the general population. The flight-crew rate was 0.15 per cent compared to 0.13 per cent for uterine cancer; 1.0 compared to 0.7 per cent for cervical cancer; 0.47 compared to 0.27 per cent for stomach or colon cancer; and 0.67 compared to 0.56 per cent for thyroid cancer.
The risk of breast cancer was higher in women who had never had children, as well as those who had three or more. Having no children was a known risk factor, noted Mordukhovich.
“But we were surprised to replicate a recent finding that exposure to work as a flight attendant was related to breast cancer exclusively among women with three or more children,” she said.
“This may be due to combined sources of circadian rhythm disruption – sleep deprivation and irregular schedules – both at home and at work.”
Male flight attendants were found to have higher rates of skin cancer – 1.2 and 3.2 per cent for melanoma and non-melanoma cancer, respectively, compared to 0.69 and 2.9 per cent for the adult population as a whole. This was especially true of the attendants working before smoking on planes was banned in the United States, in 1998.
Flight crews are regularly exposed to known and probable carcinogens, including cosmic radiation from space, circadian rhythm disruption, and possible chemical contaminants.
The authors used 2013-14 data from the Flight Attendant Health Study, which has been tracking the health of selected flight crew since 2007.
This was compared to data from 23,729 men and women with similar economic status who took part in the National Health and Nutrition Examination survey during the same years.
More than 80 per cent of the flight attendants who took part in the study were women. On average, attendants were 51 years old and had been working in the profession for more than two decades.
Insulin pill lab rat studies show promise for diabetics
Studies on laboratory rats have shown promise for a new type of insulin pill that may be able to help millions of diabetics avoid daily injections, researchers at Harvard University said.
Much more work is needed before the pill can be tested in people or possibly be made available on a wide scale. The main challenge in developing an insulin pill has been finding a way to preserve the insulin protein once it encounters stomach acid.
The experimental pill, described in the Proceedings of the National Academy of Sciences, carries insulin in a liquid, enclosed in a coating that resists acid breakdown in the stomach. The polymer coating dissolves when it reaches the alkaline environment of the small intestine, allowing liquid carrying insulin to be released.
“Once ingested, insulin must navigate a challenging obstacle course before it can be effectively absorbed into the bloodstream,” said senior author Samir Mitragotri, professor of bioengineering at Harvard. “Our approach is like a Swiss Army knife, where one pill has tools for addressing each of the obstacles that are encountered.”
It will likely be years before human trials can take place. More animal studies are needed, along with research on any toxic effects of long-term use. About 40 million people worldwide have type 1 diabetes, a condition that requires daily injections with insulin, which their bodies cannot make on their own.
According to Mark Prausnitz, chair of chemical and biomolecular engineering at Georgia Institute of Technology, the hunt for an oral insulin delivery system has been considered the “holy grail” in diabetes research.
“The implications of this work to medicine could be huge, if the findings can be translated into pills that safely and effectively administer insulin and other peptide drugs to humans,” said Prausnitz, who was not involved in the research.