Low alcohol consumption (up to 6-7 drinks per week) is not associated with the development of atrial fibrillation. The risk of atrial fibrillation seems to increase with moderate alcohol consumption (1-2 drinks per day) in men and with high alcohol consumption (different definitions) in women. These were the findings of a systematic review and meta-analysis, recently published in the scientific journal International Journal of Cardiology.
What is already known? Chronic high alcohol consumption is known to be associated with an increased risk of developing the heart rhythm abnormality ‘atrial fibrillation’. The strength of this association varies amongst studies.
What does this study add? This systematic review and meta-analysis examines the association between various levels of chronic alcohol consumption and incident atrial fibrillation.
Nine studies, incorporating almost 250.000 participants, are included in this systematic review and meta-analysis.1 The results show that high alcohol consumption (different definitions) is associated with an increased risk of atrial fibrillation in women. In men, this association is already present at moderate levels of alcohol consumption (1-2 drinks per day). No association is found between chronic low alcohol consumption (up to 6-7 drinks per week) and incident atrial fibrillation. The studies used different definitions of low, moderate, and high alcohol consumption, which could possibly account for some of the reported gender differences. Women in the highest category had a lower level of alcohol consumption than men in this category. In addition, the highest category group included a smaller number of women. More research is needed to find out at exactly what threshold the risk of atrial fibrillation increases.
Atrial fibrillation is a heart rhythm abnormality, characterised by an irregular and often accelerated pulse. Symptoms can include palpitation (being aware of your heartbeat), tiredness, shortness of breath, and dizziness or feeling faint. Whether symptoms are present or not, atrial fibrillation is one of the most common forms of abnormal heart rhythm and a major cause of stroke.2
The researchers did not study the mechanisms by which alcohol could influence the development of atrial fibrillation. However, other heart rhythm abnormalities and components of the nervous system are mentioned to possibly influence the underlying mechanisms. Although weight gain and hypertension are known independent risk factors for atrial fibrillation, it remains unclear whether the association between chronic alcohol consumption and incident atrial fibrillation is influenced by more factors.
Alcohol consumption in people with atrial fibrillation
Little is known concerning the prognosis in people with atrial fibrillation in relation to chronic alcohol consumption. Recent observational data has demonstrated that reduction in alcohol consumption to 30 g per week or less (< 3 standard drinks per week) could contribute to enhanced patient outcomes.3,4 Furthermore, previous research revealed that people with atrial fibrillation should preferably not drink alcohol.5
Strengths of this study
• Eight of the nine included studies were undertaken in the USA and/or in different European countries, with one study also incorporating Asian counties in the population. The other study was conducted in Japan.
• There is no evidence of so called ‘publication bias’ (the fact that negative or contradictory results are less likely to be published).
Limitations of this study
• The included studies use different definitions of low, moderate, and high alcohol consumption and are different in design. As a consequence, it is difficult to determine the exact amount of standard drinks per week by which the risk of atrial fibrillation increases. Standard drink definition ranges from 10 to 12 g of alcohol.
• The included studies provide little insight into patterns of drinking habits and its impact on atrial fibrillation. No distinction is made between spread drinking over the week and binge drinking.
• Both the impact of former drinking and type of alcohol consumed on the risk of atrial fibrillation are not included in this research.
1. Gallagher, C., Hendriks, J.M.L., Elliott, A.D., Wong, C.X., Rangnekar, G., Middeldorp, M.E., Mahajan, R., Lau, D.H., Sanders, P. (2017). Alcohol and incident atrial fibrillation – A systematic review and meta-analysis. International Journal of Cardiology, 246, 46-52.
2. British Heart Foundation (2017). Atrial fibrillation. Retrieved from https://www.bhf.org.uk/heart-health/conditions/atrial-fibrillation.
3. Pathak, R.K., Middeldorp, M.E., Lau. D.H., Mehta, A.B., Mahajan, R., Twomey, D., Alasady, M., Hanley, L., Antic, N.A., McEvoy, R.D., Kalman, J.M., Abhayaratna, W.P., Sanders, P. (2014). Aggressive Risk Factor Reduction Study for Atrial Fibrillation and Implications for the Outcome of Ablation: The ARREST-AF Cohort Study. Journal of the American College of Cardiology, 64(21), 2222-2231.
4. Pathak, R.K., Middeldorp, M.E., Meredith, M., Mehta, A.B., Mahajan, R., Wong, C.X., Twomey, D., Elliott, A.D., Kalman, J.M., Abhayaratna, W.P., Lau, D.H., Sanders, P. (2015). Long-Term Effect of Goal-Directed Weight Management in an Atrial Fibrillation Cohort: A Long-Term Follow-Up Study (LEGACY). Journal of the American College of Cardiology, 65(20), 2159-2169.
5. Voskoboinik, A., Prabhu, S., Ling, L., Kalman, J.M., Kistler, P.M. (2016). Alcohol and Atrial Fibrillation: A Sobering Review, Journal of the American College of Cardiology, 68(23), 2567–2576