(AP) -- Stock market slides may hurt more than your savings. New research suggests they might prompt heart attacks. Duke University researchers found a link between how a key stock index performed and how many heart attacks were treated at their North Carolina hospital shortly after the recession began in December 2007 through July 2009, when signs of recovery emerged.

The trend weakened after they did a second analysis taking into account seasons of the year. Some research suggests heart attacks are more common in winter, meaning the initial finding could have been a statistical fluke.

However, leading scientists unconnected with the work said they found it plausible and worth further research in a nationwide study.

"I do think there's merit to their first-round conclusion," said Dr. James McClurken of Temple University in Philadelphia. He is chairman of the American College of Cardiology's annual conference, where the study results were released Saturday.

Dr. Janet Wright, vice president of quality and science for the cardiology college, agreed.

"This is an intriguing study and yet another example of how stress can affect a person's heart health," she said. "It is important to be aware that personal - in this case an economic one - can be a trigger for ."

Earlier studies have found higher rates of after World Cup soccer matches, earthquakes, and other stressful events.

Mona Fiuzat, a doctor of pharmacy and researcher at Duke, had the idea for the new study. She tallied all patients who had a among those coming to the hospital for a test to detect heart disease. There were 965 heart attacks during the study period.

She then researched economic indices and how to best measure financial changes over time.

"This is not as clear as say Sept. 11," a specific date, she said. The health effects of bad financial news may emerge over weeks rather than on a single day, so she averaged heart attacks over three months, taking into account a period before and after each one, and compared these with the Nasdaq composite index.

"We felt the Nasdaq was most appropriate for the mainstream because it reflects small businesses" and therefore would have the most impact on the general public, Fiuzat said.

As stock market values decreased, the incidence of heart attacks rose; the reverse also was true, she found.

The trend did not hold up when adjusted for seasons of the year, but the study's small size, at a single hospital, does not give enough information to answer the question, some researchers said.

McClurken also questioned how much impact winter in a place like North Carolina would have on heart attack rates.

"Do they really have that much harsh seasonality in that area?" he said. This winter, yes, but not usually, he said.