Fourteen drinks a week is linked with a higher risk of health problems including stroke and embolism in patients with atrial fibrillation, according to research published in EP Europace, a journal of the European Society of Cardiology (ESC).
“Our study suggests that atrial fibrillation patients should avoid heavy alcohol consumption to prevent stroke and other complications,” said author Dr. Boyoung Joung of Yonsei University College of Medicine, Seoul, Republic of Korea.
The study included 9,411 patients with atrial fibrillation from 18 tertiary hospitals covering all geographical regions of South Korea. Patients were categorised into four groups according to their weekly alcohol consumption (one drink contains 14 grams of alcohol): abstainer/rare (0 grams/less than one drink), light (less than 100 grams/7 drinks), moderate (100-200 grams/7-14 drinks), and heavy (200 grams/14 drinks or more).
A total of 7,455 (79.2%) patients were classified as abstainer/rare, 795 (8.4%) as light, 345 (3.7%) as moderate, and 816 (8.7%) as heavy alcohol consumption.
Patients were followed-up for a median of 17.4 months for adverse events, which included stroke, transient ischaemic attack, systemic embolism (a blood clot in a limb or organ), and hospitalisation for rate or rhythm control of atrial fibrillation or for heart failure management. The researchers recorded how many patients experienced any of these events and calculated the incident rate (number of events per 100 person-years). Incident rates were 6.73, 5.77, 6.44, and 9.65 in the abstainer/rare, light, moderate, and heavy drinkers, respectively.
The researchers compared the risk of adverse events in the light, moderate, and heavy drinkers to the abstainer/rare group. Heavy drinking was associated with a 32% increased risk compared with the abstainers and rare drinkers. No significant association was observed for light or moderate alcohol consumption.
Dr. Joung said: “Our study did not find any significant association between light or moderate drinking and complications. A significant deleterious relationship with heavy drinking was identified, suggesting that heavy alcohol consumption should be avoided.”
Subgroup analyses showed that the impact of heavy drinking was more pronounced in patients with low stroke risk2 compared to those at moderate or high stroke risk. Similarly, heavy drinking was associated with a greater likelihood of unfavourable outcomes in patients without high blood pressure compared to those with high blood pressure. Higher risks were also observed in patients not using beta-blockers or antiplatelet medications compared to those taking the drugs.
Dr. Joung said: “The findings indicate that heavy drinking is particularly detrimental for atrial fibrillation patients who are considered less vulnerable to complications. Clinicians should ask patients about their alcohol consumption and take it into account when calculating their stroke risk.”
He concluded: “While heavy drinking should be strongly discouraged among atrial fibrillation patients, moderate drinking seems to be safe.”