Phillips' research, published in the December 2001 issue of the British Medical Journal, may provide the most persuasive evidence to date linking extreme psychological stress and fatal heart attacks. In the study, Phillips, a well-known authority on mortality trends and the social and psychological factors affecting them, collaborated with UCSD Mathematics Professor Ian Abramson and UCSD students George Liu, Kennon Kwok, Jason Jarvinen, Wei Zhang.
"I have often wondered if people could indeed die by fright," said Phillips, "and if so, how this could be investigated quantitatively. I recalled that in 'The Hound of the Baskervilles,' Sir Charles Baskerville dies of a fatal heart attack, apparently because he is frightened to death by the hound. Since Arthur Conan Doyle was a physician as well as an author, I wondered if his story was based on medical intuition or literary license, i.e. were fatal heart attacks and stress linked in fact as well as fiction?"
Although numerous laboratory studies have shown cardiovascular changes following psychological stress, for ethical reasons only non-fatal stressors can be studied in the laboratory and one may not be able to generalize beyond these mild stressors to determine if, in the real world, fatal heart attacks are precipitated by extreme stress.
"The challenge was to find a way of testing this hypothesis that would circumvent the ethical problems of the laboratory experiment and yet retain some of its vigor," explained Phillips. "The best solution seemed to be to use a natural experiment - a real life event that met certain criteria. First, this real life event had to have distressing psychological effects on one segment of the population but not on others. In addition, it shouldn't actually be a dangerous event - it should only be perceived as such. Lastly, this event should not be linked to any changes in the quality of medical services."
It was not easy for Phillips and his collaborators to find such an event that met these criteria, but they did. The real life event they choose is connected to a Chinese and Japanese superstition. In Mandarin, Cantonese, and Japanese, the words "death" and "four" are pronounced nearly identically, and consequently the number "four" evokes discomfort and apprehension in many Chinese and Japanese people. Because of this, the number "four" is avoided and omitted in some Chinese and Japanese floor and room numberings, restaurants, and telephone numbers. In addition, the mainland Chinese air force avoids the number "four" in designating its military aircraft, apparently because of the superstitious association between "four" and "death."
The study by Phillips and his co-authors finds that cardiac deaths peak on the fourth of the month for Americans of Chinese and Japanese descent, and that this pattern is not seen among whites. The study used computerized U.S. death certificates to examine more than 200,000 Chinese and Japanese deaths, and 47,000,000 white deaths, from 1973 to 1998.
"Conan Doyle suggests that Sir Charles Baskerville was particularly susceptible to a stress-induced heart attack because he had a chronic heart condition," said Phillips. "If Doyle's medical intuition was correct, deaths from chronic heart disease should display a particularly large fourth-day peak. Sir Charles Baskerville's superstitious fear of an avenging spectral hound was shared and reinforced by his neighbors. Similarly, Chinese and Japanese superstitious fears are likely to be stronger where they are reinforced by large Chinese and Japanese populations."
Phillips' evidence supports both of these expectations. For U.S. Chinese and Japanese, there are 13% more cardiac deaths than expected on the fourth of the month. This fourth-day increase is still larger (27% above expected) in California, where Chinese and Japanese populations are concentrated.
Phillips and his co-authors tested nine, alternative, non-psychosomatic explanations for their findings, including the possibility that, on the fourth, Chinese and Japanese might change diets, increase alcohol consumption, refuse medicines, or overstrain themselves. The researchers concluded that their data suggest a link between psychological stress and heart attacks.
"Our findings are consistent with the existence of psychosomatic processes, with the scientific literature, and with a famous non-scientific story. The 'Baskerville effect' seems to exist both in fact and in fiction, and suggests that Conan Doyle was not only a great writer, but a remarkably intuitive physician as well."
Phillips has published extensively on the role that psychosomatic factors can play in precipitating and delaying death among certain groups. He has studied the effects of gambling and medical errors on mortality rates as well as the ability of some people to prolong their lives for a significant event. For more information on Phillips' work visit his web site at: http://weber.ucsd.edu/~dphillip/ To view the British Medical Journal paper in its entirety please go to: http://weber.ucsd.edu/~dphillip/baskerville.html
Note: David Phillips can be contacted directly at 858.534.0482 or firstname.lastname@example.org
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