Coffee consumption is linked to reduced risk of heart failure

A large analysis looked at hundreds of factors that could influence the risk of heart failure and found one dietary factor in particular associated with a lower risk: coffee consumption.

Heart failure, sometimes called congestive heart failure, occurs when the heart muscle weakens and cannot pump blood efficiently. It can be caused by high blood pressure, disease of the heart valves, heart attack, diabetes, and other diseases and conditions.

The analysis included extensive data over decades from three large health studies with 21,361 participants and used a method called machine learning that uses computers to find meaningful patterns in large amounts of data.

“Usually, researchers choose things they suspect are risk factors for heart failure – smoking, for example – and then look at smokers versus non-smokers,” said lead author Dr David P. Kao, assistant professor of medicine at the University. from Colorado. “But machine learning identifies predictors of increased or reduced risk, but which you may not have thought of.”

Using this technique, Dr. Kao and his colleagues found 204 variables associated with the risk of heart failure. Next, they looked at the 41 most important factors, including smoking, marital status, BMI, cholesterol, blood pressure, and consumption of various foods. The analysis is in circulation: heart failure.

In all three studies, coffee consumption was associated more strongly than any other dietary factor with a lower long-term risk of heart failure.

Drinking one cup a day or less had no effect, but two cups a day conferred a 31% reduced risk and three or more cups reduced the risk by 29%. There weren’t enough subjects who drank more than three cups a day to know if more coffee would further reduce the risk.

This isn’t the first study to find health benefits in drinking coffee. “In other studies, coffee consumption was also associated with a reduced risk of stroke and coronary heart disease,” said Dr Kao, although “we did not find this in our study” .

The study could not report on the different types of coffee or brewing methods, or the use of additives like sugar or cream. There was no association with a decreased risk of heart failure with drinking decaffeinated coffee – in fact, one study suggested it might increase the risk.

Caffeine may be an important factor, the authors suggested, but the mechanism of the effect is not known. The study did not examine the effect of tea or other foods containing caffeine.

Unlike conventional observational studies that start with a hypothesis and then build evidence for it, this machine learning analysis began without an initial hypothesis. Dr Harlan Krumholz, a professor of medicine at Yale who was not involved in the work, called the approach “innovative,” but noted that one limitation was that “many other behaviors likely followed coffee consumption. , and it is difficult to disentangle the specific effect. of coffee from other things that may accompany it.

Should you start drinking coffee or increase the amount you already drink to reduce your risk of heart failure? “We don’t know enough about the results of this study to recommend this,” Dr Kao said, adding that more research is needed. “It would be helpful if we could determine if drinking an extra cup would prevent some complications.”