Occasional coffee may trigger rare heart attacks
People who drink only an occasional cup of coffee may be at higher risk of heart attack than heavy drinkers, a new study has found.
The study, which found a correlation between drinking coffee and increased risk of heart attack in a small percentage of infrequent coffee drinkers, is sure to heat up the debate on the health risks of the popular caffeinated beverage.
According to a study in the September issue of the journal Epidemiology, certain people were susceptible to a heart attack within an hour of drinking only one cup of coffee.
Those at highest risk were:
- People who drink coffee rarely;
- Those who lead inactive lifestyles;
- and people with existing risks for coronary heart disease.
Risk of heart attack rose 60 per cent in moderate coffee drinkers, defined as those who typically drink two or three cups a day. The risk quadrupled for light coffee drinkers, who drink one cup or less than a cup per day.
Risk was more than doubled for patients with three or more risk factors for coronary heart disease, such as high blood pressure, high cholesterol, obesity, diabetes and smoking.
There was no measurable impact on heavy coffee drinkers.
Researchers speculated that the bodies of infrequent coffee drinkers are less tolerant of the effects of caffeine.
Based on their findings, the researchers said that people at risk for coronary heart disease who drink coffee rarely might want to consider avoiding it altogether.
For the study, Ana Baylin of Brown University and her colleagues at Harvard School of Public Health examined 503 cases of non-fatal myocardial infarction between 1994 and 1998 in Costa Rica.
Patients were asked about their coffee consumption prior to their heart attacks and researchers examined socio-demographic data, along with the patients' lifestyles and medical histories.
The researchers were exploring a theory that a short-term increase in blood pressure and sympathetic activity in the nervous system could cause a heart attack by having an impact on atherosclerotic plaque.
Caffeine, the active ingredient in coffee, is known to increase sympathetic nerve activity, which raises blood pressure.
The impact of coffee drinking and caffeine consumption has been the subject of many studies, but Baylin's study is the first to measure immediate rather than long-term effects. The study examined only the first hour after the patients drank coffee.
Baylin's study is sure to add fuel to the debate over the health impact of coffee.
The New York Times reported Tuesday that a review of a series studies published in the Journal of the American Medical Association said there is evidence to support the argument that the beverage could reduce risks for certain diseases, such as diabetes, heart disease and cirrhosis of the liver.
www.ctv.ca
|
