Contrary to findings from an earlier study, new research suggests that coffee lovers don't face an increased risk of heart failure.
Researchers found that among more than 37,000 middle-aged and older Swedish men, those who regularly drank coffee were no more likely to develop heart failure than those who infrequently, if ever, drank the beverage.
The findings, reported in the American Heart Journal, add to evidence that coffee may not be the heart-health threat it was once suspected to be.
The initial studies suggesting that heavy coffee consumption might contribute to heart attacks or other cardiac problems were mainly retrospective – asking heart-attack sufferers about their coffee consumption and comparing them with people who had never had a heart attack, for example.
But more recent studies have been better designed to weed out a true association. These so-called prospective studies have first asked people about their coffee intake and then followed them over time to record new cases of heart trouble.
Those studies have generally linked coffee to either a neutral or even a protective effect on heart health, said Dr Emily Levitan, one of the researchers on the new study.
Few studies on heart failure
Heart failure, however, has been little studied as compared with heart attack, noted Levitan, who was with Beth Israel Deaconess Medical Center in Boston at the time of the study and is now based at the University of Alabama at Birmingham.
Heart failure is a chronic condition in which the heart muscle is weakened and can't pump blood efficiently enough to meet all the body's needs, leading to symptoms like fatigue and breathlessness on exertion.
A 2001 study raised concerns that heavy coffee drinking might contribute to heart failure. It found that of roughly 7,500 Swedish men, those who drank five or more cups of coffee per day had a higher risk of developing heart failure than men who drank less than that.
Based on that study, a recent statement from the American Heart Association (AHA) noted that coffee consumption might raise the risk of heart failure, but added that more research is needed to confirm that possibility.
The AHA statement motivated the current study, Levitan told Reuters Health.
No clear relationship
She and her colleagues found that among 37,315 men ages 45 to 79, 784 went on to develop heart failure over nine years. The researchers found no clear relationship between the men's reported coffee intake at the outset and their risk of developing heart failure.
Whether the findings apply to men with existing heart problems isn't known, according to Levitan. Going into the study, none of the men had a history of heart attack; heart-muscle damage from a heart attack is one of the major causes of heart failure.
Nor did the study include women. It's possible, Levitan noted, that the results could be different for women, but that would be unlikely.
"I don't think there's any strong evidence of an association between coffee and heart failure," she said. It would be "premature", Levitan added, for people to give up coffee in an effort to prevent the disease.
(Reuters Health, October 2009)