Drinking less alcohol confers cardiovascular benefits among heavy drinkers

Reducing alcohol consumption helps lower the risk of future adverse cardiovascular events, especially angina and ischaemic stroke, among people who drink heavily, according to a study.

For the study, researchers used data from the Korean National Health Insurance Service–Health Screening database and identified Korean citizens aged 40 to 79 years who had national health insurance coverage. A total of 21,011 individuals with heavy alcohol consumption at baseline (mean age 56.08 years, 90.3 percent men) were included in the study. Heavy drinking was defined as consumption of more than 4 drinks (56 g) per day or more than 14 drinks (196 g) per week for men and more than 3 drinks (42 g) per day or more than 7 drinks (98 g) per week for women.

Habitual change in heavy alcohol consumption during the second health examination period was assessed using self-reported questionnaires. The primary outcome was the occurrence of major adverse cardiovascular events (MACEs), defined as a composite of nonfatal myocardial infarction or angina undergoing revascularization, any stroke accompanied by hospitalization, and all-cause death.

Of the participants, 14,220 (67.7 percent) sustained heavy drinking whereas 6,791 (32.2 percent) shifted to mild to moderate drinking. Over a follow-up of 162,378 person-years, MACE occurred with significantly greater frequency in the sustained heavy drinking group than in the reduced drinking group (817 vs 675 per 100,000 person-years; p=0.003).

In propensity score matching analysis, reduced alcohol consumption reduced the risk of MACEs by 23 percent compared with sustained heavy drinking (hazard ratio [HR], 0.77, 95 percent confidence interval [CI], 0.67–0.88). This association was driven by a significant reduction in the incidence of angina (HR, 0.70, 95 percent CI, 0.51–0.97) and ischaemic stroke (HR, 0.66, 95 percent CI, 0.51–0.86).

The cardiovascular benefits with reduced alcohol intake were consistently observed across various subgroups of participants.