(LOS ANGELES) -- Football fans across the country will watch the Packers battle the Steelers Sunday in the Super Bowl. And for fans in Green Bay or Pittsburgh, the big game could be a heart-stopper, literally, in light of research suggesting that a Super Bowl defeat might boost the risk of cardiac death.
"Fans can develop an emotional attachment to their favorite team," said Dr. Robert Kloner, professor of medicine at the University of Southern California's Keck School of Medicine and director of research at Good Samaritan Hospital's Heart Institute in Los Angeles.
"And when there's an emotional response, the sympathetic nervous system gets jazzed up and releases adrenaline, causing a surge in heart rate, an increase in blood pressure and an increased demand for oxygen by the heart."
Kloner and colleagues had previously reported in April 2009 an increased incidence of heart-related deaths in Los Angeles two weeks after the city's 1980 Super Bowl loss. The group has now taken a closer look at who was most vulnerable in a study published in Clinical Cardiology, released Monday.
"We've known for many years that there are chronic risk factors for cardiac death, such as high cholesterol, high blood pressure and smoking," Kloner said. "But we're becoming increasingly aware of certain acute risk factors, such as emotional stress. I think that these stressors may add up."
The much-loved L.A. Rams were the underdogs in 1980 in an intense and emotional game being played close to home at the Rose Bowl Stadium in Pasadena. The Rams had the lead going into the fourth quarter, but lost 31-19 to the Pittsburgh Steelers.
Despite being sixth-seed in the National Football Conference playoffs this year, the Green Bay Packers are favored going into Sunday's game in Dallas. But Steelers fans might be less suited to handle a Super Bowl loss, according to a national survey.
Of 185 U.S. cities, Pittsburgh ranked 66th in emotional health, 123rd in physical health and 106th in healthy behavior, according to Gallup-Healthway's 2009 Well-Being Index. Green Bay scored better, ranking 33rd in emotional health, 25th in physical health and 84th in healthy behavior.
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