Epidemiology

Effect of drinking on heart disease risk differs between men and women

Last Updated: 2006-05-25 19:01:20 -0400 (Reuters Health)

NEW YORK (Reuters Health) - The frequency of alcohol consumption is inversely associated with the risk of coronary heart disease (CHD) among middle-aged men, according to a study in Denmark. But for women of the same age, it appears that the risk may be affected more by the amount consumed rather than the frequency of consumption.

Multiple studies have demonstrated that moderate drinking reduces the risk of heart disease among men compared with abstainers. However, the effect of alcohol consumption on CHD among women has not received the same scrutiny as has that of men, Dr. Janne Tolstrup and her associates note in their article in the British Medical Journal for May 27.

To determine the effects of alcohol drinking patterns, Dr. Tolstrup, from the National Institute of Public Health in Copenhagen, and her associates requested that subjects between the ages of 50 and 65 complete food frequency questionnaires, including their alcohol consumption, between 1993 and 1997. Included were approximately 28,000 women and 25,000 men who were free of cardiovascular disease at baseline.

Data regarding the incidence of CHD and mortality were obtained from Danish registries. During median follow-up of 5.7 years, 749 women and 1283 men developed CHD.

Women who drank alcohol at least once each week had lower risk of CHD than women who abstained. However, the risk did not appear to change with frequency of drinking, since the hazard ratio (HR) for drinking one day per week (0.64) was similar to that of women who drank every day (0.65).

In contrast, women who drank the most generally had the lowest risk. For example, the HR for consuming 1-6 drinks on 2 to 4 days/week had an HR of 0.78, while for those who drank at least 14 drinks at the same frequency, the HR was 0.27 (p for trend < 0.0001).

Among the men, drinking frequency was inversely associated with CHD. The hazard ratio was 0.93 for drinking one day per week compared with those who didn't drink, decreasing to 0.59 for men who drank daily (p for trend < 0.0001).

The amount didn't seem to matter as much among men, since the HR was 0.80 for men who drank up to 6 drinks 2-4 times/week, compared with an HR of 0.91 for those who drank 14 to 20 drinks and 0.67 for those who drank at least 21 drinks (p = 0.22).

Dr. Tolstrup's team suggests that the differences between sexes may be explained by differences in alcohol pharmacokinetics. They also note that alcohol may affect levels of high density lipoprotein, fibrinogen or platelet aggregation.

Regardless of the mechanism, the researchers warn that their findings should not be used to condone heavy drinking, which increases mortality by causing liver disease, cancer, and traffic accidents.

Dr. Annie Britton, from University College London, echoes that advice in an accompanying editorial, noting that "as a population we are drinking well above the optimum level for health."

"The physiological effects of regular moderate drinking and binge drinking are markedly different," she adds, with the latter associated with increased morbidity and mortality.

BMJ 2006;332:1224-1225,1244-1247.