Staying Upbeat: Women With Heart Disease May Benefit From Drinking Wine, Swedish Study Finds
Wine drinkers had healthier heart-rate variability than women who drank other beverages
A study of Swedish women hospitalized for heart problems found that those who drank a little wine daily after their hospital stay tended to have better-performing hearts than women who didn't drink or who preferred beer or spirits.
The research, published in the February issue of the medical journal Heart, looked at the body's ability to change its heart rate effectively, or its heart-rate variability (HRV). A person's HRV can be used to predict their chance of survival after a heart attack. When the body stops to rest, a healthy heart changes rhythm, pumping less blood. When the body begins exercising, a healthy heart begins to pump more, to provide oxygen to the cells. HRV measures these beat-to-beat alterations in heart rate. According to the study's authors, the higher the HRV, the healthier the heart.
"Wine intake was associated with an increased HRV," wrote the authors, headed by Imre Janszky at the Karolinska Institute in Stockholm. "In contrast, consumption of beer and spirits did not relate significantly to HRV."
The team said that few scientific studies have been done on the possible effects alcohol may have on HRV, although previous research has found that moderate alcohol consumption may reduce the risk of having a second heart attack and may help lower levels of bad cholesterol in heart attack patients. The lack of data is unfortunate, the authors wrote, "given the compelling evidence that decreased HRV is an independent predictor of coronary heart disease."
The researchers recruited 102 women under the age of 75 who were hospitalized for either a heart attack or heart surgery. The women were studied during their recovery program over a period of up to 16 months. Every few months, the women filled out questionnaires on their dietary habits, which included the type of alcohol they preferred, if any, and how much they drank in a typical day. Several times during the study, each of the women had to wear a heart monitor for 24 hours straight to measure their HRV. To account for any variations in their consumption patterns, each woman's set of HRV results were averaged.
Because the women tended not to drink very much, the scientists modified the definitions of light and moderate consumption. The women were grouped as nondrinkers, light drinkers (up to half of a standard drink per day) and moderate drinkers (more than half of a standard drink per day). A standard drink was defined as containing about 10 grams of alcohol. (In comparison, in the United States, a standard drink--4 ounces to 5 ounces of wine, a shot of liquor or 8 ounces to 12 ounces of beer-- is defined as having 12 grams to 14 grams of alcohol.) Women who significantly changed their drinking habits during the study were excluded from the results.
The heart monitor data was compared to the women's drinking habits. The results were adjusted to take account of whether the women smoked, had a history of diabetes or used hormone replacement therapy, as well as of the women's education levels, income and body mass index.
The scientists found that the women who drank beer or spirits, in any amount, had an average HRV similar to that of the nondrinkers. The wine-drinking women, however, showed a higher average HRV than the nondrinkers, regardless of the amount of wine they consumed.
When the results of the women in the light and moderate wine-drinking groups were averaged, they had an HRV of 3.89. The nondrinking women, on the other hand, had an HRV of 3.59. A typical HRV for someone without heart disease could range from 5.0 to 7.0.
Though the study had several limitations and the data on women may not apply to the general population, the scientists were still pleased with the findings. "Our results may contribute to the understanding of the complex relation of alcohol consumption with CHD," they wrote.
