In work that illustrates the negative influence that mind can wield over body, a new study provides perhaps the strongest evidence yet that psychological stress can increase the risk of cardiac death. A report describing this so-called Baskerville effectnamed for the fate of a character in Sir Arthur Conan Doyle's The Hound of the Baskervilles who succumbs to a stress-induced heart attackappears in the current issue of the British Medical Journal.

To test this hypothesis, sociologist David Phillips of the University of California, San Diego, and colleagues focused on a Chinese and Japanese superstition that holds that the number four is extremely unlucky. Analyzing U.S. death certificates representing more than 200,000 Chinese and Japanese deaths and some 47 million Caucasian deaths that occurred between the years of 1973 and 1998, the team found that deaths among the Chinese and Japanese peaked on the fourth of each month. Indeed, 13 percent more cardiac deaths occurred in Chinese- and Japanese-Americans on the fourth day of the month than would be expected. The same pattern did not characterize Caucasian deaths.

"Our findings are consistent with the existence of psychosomatic processes, with the scientific literature, and with a famous non-scientific story," Phillips asserts. "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."