HEART ATTACKS TWICE AS DEADLY FOR WOMEN THAN MEN UNDER 50.

Byline: Linda A. Johnson Associated Press 

A heart attack is twice as likely to be fatal for a woman as for a man younger than 50, but the gap narrows and eventually disappears later in life.

The discovery by Yale University researchers suggests that biological factors, not differences in medical care, largely explain why heart attacks are more deadly for women.

The researchers found, as many others have, that women's heart attacks in general are more likely to be fatal. Seventeen percent of female heart attack victims die while they are still in the hospital, compared with 12 percent of males.

When the researchers broke the numbers down by age, however, they came to the surprising conclusion that the difference results entirely from a much higher death rate among the younger victims.

Heart attacks are especially rare among women younger than 50, but they kill 6 percent of those who experience them, compared with 3 percent of male victims under 50. By age 75, the death rate for both sexes is about equal, around 19 percent.

Over the years, experts have speculated about why heart attacks are more deadly for women, and some have suggested that differences in medical treatment play a role. While this may be part of the story, the new work suggests that biology is probably a more important factor.

The study, directed by Dr. Viola Vaccarino, was based on a review of the records of 384,878 heart attack victims between 1994 and 1998. It was published today in the New England Journal of Medicine.

``Probably biological mechanisms play a major role, but we need to look at the big picture and take into account all aspects of the women and their care,'' Vaccarino said. ``Heart disease is the No. 1 killer of women,'' she said, noting this is true for women younger than 65 as well as those who are older.

In earlier work, the Yale team and other researchers found that women wait hours longer after a heart attack before going to the hospital, then are treated less aggressively than men. That delay, which allows further damage to the oxygen-starved heart, results partly because women tend to doubt they are experiencing heart attack symptoms. Sometimes they feel only pressure or a burning feeling, not crushing pain.

The researchers also noted that younger female victims are more likely than men to have other health problems, such as diabetes, high blood pressure and heart failure.

Still, the treatment differences and the poorer overall health of younger women who died of heart attacks only explained one-third of the mortality difference. For each five years younger than 75, women still had a 7 percent higher risk of dying after a heart attack than men with equal overall health and equal treatment. By age 80, the men had a slightly higher risk.

In an accompanying editorial, Dr. Laura F. Wexler of the University of Cincinnati called the discovery striking and new.

``Do these women have some especially potent risk factor, or do they lack a protective factor that is normally present in women?'' she asked.

Typically, heart disease afflicts women about a decade later in life than men, probably because the female hormone estrogen protects their hearts before menopause. Those who are struck at an early age may have differences in the way their bodies use estrogen.

In another study cited in the journal, researchers directed by Dr. Judith S. Hochman of St. Luke's-Roosevelt Hospital Center in New York City looked at records of 12,142 men and women who had serious heart attacks, milder heart attacks or severe chest pain.

In all three categories, women were up to twice as likely to suffer serious complications. Among those who had heart attacks, the women were 50 percent more likely to die within 30 days.

``Taken together, these studies suggest that there are gender-specific factors at play in heart attacks that are not necessarily related to differences in care but to the underlying disease process,'' said Dr. Lynn A. Smaha, president of the American Heart Association.

Whatever the reasons, several experts stressed the need for women to seek testing and treatment at the first hint of heart trouble and to try to prevent it by controlling their weight, exercising and quitting smoking.

``We really have to look for new treatments'' because those now being used are based mainly on research of men and don't work as well on women, added Dr. Kevin Schulman of Georgetown University Medical Center in Washington.