Past studies have found upswings in heart-related deaths after a stressful mass event, anything from natural disasters such as earthquakes to sports disasters like a home team losing the Super Bowl.

But the current study, published in the American Journal of Cardiology, found no evidence that the October 2008 crash led to a spike in deaths, from heart problems or otherwise, in Los Angeles.

"It was surprising, given what other studies have found," said lead researcher Bryan Schwartz, of the Heart Institute at Good Samaritan Hospital in Los Angeles.

What the findings suggested is that while the stock market crash was stressful, it may not have been an intense, personal emotional trigger for most Angelenos, he told Reuters Health.

There is plenty of research suggesting that for people with heart disease risk factors, such as high blood pressure or diabetes, acute stress can temporarily raise the odds of a cardiac "event" such as a heart attack.

Acute stress can be physical, like sudden heavy exertion, or it can be emotional, Schwartz said, noting that this study did not negate the importance of acute stress in heart risks.

But the stress surrounding the 2008 crash may not have been enough to cause a "population shift" in heart disease deaths, said Robert Kloner, senior researcher on the study.

The researchers set out to investigate a possible relation between a stock market crash and cardiac death in a large population within the United States. Their findings were based on LA county death certificate data and daily stock market figures for 2005 through the end of 2008.

The researchers found no evidence that the October market crash affected death rates, overall or from heart complications specifically. After the crash, deaths remained at or below the seasonal average.

For 2008 overall, the death rate from heart disease in LA was 0.12 percent, slightly lower than the 0.14 percent in 2005.

Their findings contrast to a study in Shanghai, China, where the stock market woes of 2008 were tied to a spike in deaths.

A study published last year by Chinese researchers found that every 100-point change in the Shanghai stock market index during 2007 and 2008 was linked to a five percent rise in heart-related deaths.

But the link may be due to population differences in Shanghai and LA, the researchers said.

In Shanghai, many new investors in China's boom years of 2006 and 2007 were elderly and already at increased risk of heart disease. And unlike LA investors, who typically leave their money in the hands of professionals, Shanghai investors were watching the market themselves, monitoring it daily.

"They were more personally and emotionally involved in it," Schwartz said, speculating that market volatility may have been a bigger risk for Shanghai investors' hearts compared to their LA counterparts.

By contrast, one risk factor for cardiac death did stand out consistently -- winter, even in LA's mild climate.

Holiday stress is often blamed for the effect, but Kloner also recommended maintaining a healthy diet and regular exercise during the winter, when those habits often tend to fall away. Low temperatures can also have potentially risky effects on the cardiovascular system, such as making the blood more prone to clotting. SOURCE: bit.ly/wCMwLE

(Reporting from New York by Amy Norton at Reuters Health; editing by Elaine Lies and Bob Tourtellotte)

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