High-flying executives from some of Britain's leading companies are to take a new saliva test that will be used to predict whether they are likely to fall ill as a result of the stress of life at the top.
The saliva test, which monitors the state of a person's immunity against infections, is already being used on leading sportsmen and women as a method of guarding against the risk of developing chronic ill health during intensive training, which is thought to suppress resistance to disease.
It is hoped that long-term monitoring of the immune antibodies in a person's saliva will give doctors early warning against changes to the immune system due to stress that could result in chronic ill health from which a person may find it difficult to recover.
Lynn Fitzgerald, of Brunel University College, said the saliva test is proving to be an accurate indicator of susceptibility to serious illness as a result of intense physical or psychological stress. "American organisations and increasingly British ones are really becoming quite serious about monitoring and keeping their staff healthy. By next year we might expect to be studying some executives in the major corporations."
Dr Fitzgerald told the British Association that the level of immunity in saliva is a "first line of defence" against most viruses that are inhaled or swallowed. "When we look at when an athlete is most rested we find a level that seems to be associated with good health for them," she said. "If we see a precipitate decline in this level ... we have found that, if they get any infections, it tends to take them longer to recover."
British athletes, including some soccer players, are already believed to be taking the saliva tests, although Dr Fitzgerald said she "is not at liberty" to comment on who they are. South Africa's leading rugby teams have expressed an interest in the test for monitoring their players next season, she said.
"This is not a predictor for getting an infection, it's a predictor we think for a state of compromised immunity. If they have a robust immune system then they might recover in two days from a cold. But if they get something in this rather depressed state, it'll be there for three weeks and it could develop into a chronic fatigue thing where they are out for a season or a few months."
When it comes to employees, the saliva test could be used to advise them when it is a good time to take a holiday, she said.
An expert on stress, Nancy Rothwell, of Manchester University, said: "Just because you're happy it doesn't mean that you are never going to get ill. Nevertheless, there is now reasonable evidence to suggest that stress affects immune function and susceptibility to or recovery from disease."
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