Risk of death within five years of diagnosis is 30 percent to 50 percent. Swedish researchers studied 39,805 people 20-90 years old who didn't have heart failure when the study began in 1997. Researchers assessed their total and leisure time activity at the beginning of the study and followed them to see how this was related to their subsequent risk of developing heart failure. They found that the more active a person, the lower their risk for heart failure.
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