About 40 percent of U.S. women admitted to a hospital for a heart attack never had chest pain, researchers said. The study, published in The Journal of the American Medical Association, found about 31 percent of men admitted to the hospital admitted didn\'t experience chest pain, and 15 percent of women treated for heart attack died, versus 10 percent of the men. Study author John G. Canto of the Lakeland Regional Medical Center in Florida and colleagues used data from a national registry of people admitted to hospitals for heart attack from 1994 to 2006 involving more than 1 million people, The New York Times reported. The study found women age 55 and under who presented at the hospital with no chest pain had higher mortality than men within the same age group, who had classic heart attack symptoms including chest pain. For women age 55 and older, the difference dropped the older the women were.