March 2nd, 2015
Moderate Coffee Consumption Linked to Lower Coronary Calcium
Larry Husten, PHD
The relationship of coffee and cardiovascular disease has been difficult to assess. Although early studies found a possible increased risk associated with heavy coffee consumption, more recent studies have found the opposite. Now a new study published in Heart finds that people who consume moderate amounts of coffee may be less likely to have atherosclerosis.
In a study of more than 25,000 people in South Korea without known cardiovascular disease, researchers examined the relationship between various levels of coffee consumption and the coronary artery calcium (CAC) score as measured by a multidetector CT scan. They found that people who drank coffee were less likely to have calcium in their coronary arteries than nondrinkers. They described the relationship as U-shaped, with the lowest levels occurring in the people who drank 3 or 4 cups of coffee each day. The overall pattern remained present after multiple analyses adjusting for risk factors.
“Our findings are consistent with a recent body of literature showing that moderate coffee consumption may be inversely associated with cardiovascular events,” the authors wrote. But they concluded that “further research is warranted to confirm our findings and establish the biological basis of coffee’s potential preventive effects on coronary artery disease.”
Despite the recent positive findings, the senior author of the study, Eliseo Gualiar, an epidemiologist at Johns Hopkins, said in an email that he was “concerned that the role of coffee in preventing cardiovascular disease is exaggerated. Our study was an observational association study that by itself cannot prove causation.” However, Gualiar said the findings were “reassuring, in the sense that coffee intake, a very common habit, is not associated with increased cardiovascular risk.” Moderate coffee drinkers, he said, “should not be concerned that coffee is increasing their risk of cardiovascular disease. On the other hand, we believe that at this point we should still not recommend drinking coffee for preventing cardiovascular disease.”
Yale University cardiologist Harlan Krumholz said he agreed with Gualiar: “It is important that the public interpret this study in that context. People should not feel an imperative to drink coffee to lower risk, but those who enjoy coffee may take comfort in a study that failed to identify a risk and even suggested a benefit.”
Gualiar’s perspective was also largely endorsed by another expert not involved with the study, Thomas Whayne Jr., a cardiologist at the University of Kentucky, who disclosed that he is “a major fan of coffee as my favorite beverage.” “The bottom line,” he says, “is that, for the patient who loves coffee in moderation, there should be no restriction to moderate intake even in the severe heart-failure patient, and patients should be encouraged to enjoy coffee unless there were to be an unpleasant association with something such as increased arrhythmias.” Whayne said that cardiologists “should not recommend coffee, even in moderation, to prevent coronary atherosclerosis” but that they can reassure patients that there may be some benefit and, at worst, very little cardiovascular risk.”