In a 2017 study, researchers investigated the link between alcohol consumption and cardiovascular disease. They report that moderate alcohol consumption reduces the risk of ten cardiovascular conditions over non-drinking, occasional drinking, former drinking, and heavy drinking.
The relationship between alcohol consumption and cardiovascular disease is contested. Some studies have found moderate drinking to have a protective effect on cardiovascular disease compared to non-drinking and heavy drinking. Critics, however, have suggested unclear designations – that is, grouping lifelong abstainers, former drinkers, and occasional drinkers as non-drinkers and failing to define different types of cardiovascular disease – may have biased study results. If the effect of alcohol consumption on cardiovascular disease is to be clarified, and recommendations concerning cardiovascular health are to be made or revised accordingly, such factors should be taken into account.
In a 2017 UK study published in the British Medical Journal, researchers investigated the link between alcohol consumption and 12 cardiovascular diseases. The Clinical Practice Research Datalink (CPRD) health records of 1,937,360 patients over the age of 30 with no history of cardiovascular disease were examined. Self-reported drinking behaviour within the five years leading up to the study and alcohol abuse history were used to classify participants: non-drinkers who were lifelong abstainers or current non-drinkers; former drinkers who were ex-occasional, moderate, or heavy drinkers; occasional drinkers who rarely or occasionally drank; moderate drinkers who drank lightly or sensibly on a daily or weekly basis; and heavy drinkers who were alcohol abusers or drank above sensible levels. Patient records were followed until the date of first diagnosis with a cardiovascular disease, death, or withdrawal from the CPRD system. Twelve cardiovascular diseases were investigated: chronic stable angina, a type of consistent, usually exertion-related chest pain; unstable angina, irregular chest pain associated with heart attacks; heart attacks; death from coronary heart disease without warning signs; heart failure; cardiac arrest; transient ischemic attacks (TSA), temporary ischemic (vessel blockage-related) strokes; ischemic strokes; intracerebral hemorrhage, strokes caused by internal bleeding within the brain; subarachnoid (between the brain and skull) hemorrhage; peripheral arterial disease; and abdominal aortic aneurysms (AAA). Age, sex, body mass index, socioeconomic status, smoking, and diabetes status, high-density lipoprotein (HDL; “good cholesterol”), blood pressure, the use of blood pressure medications or statins, and the receipt of dietary advice were taken into account.
Moderate drinking was associated with more favourable cardiovascular outcomes overall compared to other drinking patterns. Compared to moderate drinkers, non-drinkers were 33% and former drinkers were 23% more likely to have a diagnosis of unstable angina. Non-drinkers were 32%, former drinkers were 31%, and occasional drinkers were 14% more likely to have a heart attack; heavy drinkers, however, were 12% less likely. Non-drinkers were 56%, heavy drinkers were 21%, former drinkers were 40%, and occasional drinkers were 13% more likely to suffer coronary death without warning signs. Non-drinkers were 24%, heavy drinkers were 22%, former drinkers were 40%, and occasional drinkers were 19% more likely to experience heart failure. Non-drinkers were 12%, heavy drinkers were 33%, and former drinkers were 16% more likely to experience an ischemic stroke. Non-drinkers were 22%, heavy drinkers were 35%, former drinkers were 32%, and occasional drinkers were 11% more likely to have peripheral arterial disease. Non-drinkers were 32% and former drinkers were 23% more likely to have an AAA. Heavy drinkers were 50% and former drinkers were 37% more likely to suffer cardiac arrest. Heavy drinkers were 11% and former drinkers were 16% more likely to have a TSA. Heavy drinkers were also 37% more likely to have an intracerebral hemorrhage and 7% less likely to have chronic stable angina.
With respect to cardiovascular disease(other than chronic stable angina), total cardiovascular disease-related mortality, non-cardiovascular-related mortality, and all-cause mortality, non-drinkers, former drinkers, and heavy drinkers were at increased risk compared to moderate drinkers. For total coronary heart disease (heart attack and coronary death without warning signs), however, heavy drinking was not associated with increased risk over moderate drinking. Among female participants, there was no link found between heavy drinking and heart failure. Further, the increased risk of heart failure was shallower for female compared to male non-drinkers.
Overall, the findings suggest that moderate alcohol consumption reduces the risk of 10 of the 12 cardiovascular diseases investigated in this study compared to non-drinking, occasional drinking, former drinking, or heavy drinking. Moderate drinking, however, did not significantly reduce the risk of subarachnoid hemorrhage over any other drinking pattern and was associated with greater risk than heavy drinking for heart attacks and stable angina. Both non-drinkers and heavy drinkers were found to have an increased risk of coronary death without warning signs. As such, it may benefit clinicians to also consider non-drinking as a risk factor for coronary death and tailor recommendations accordingly. It should be noted that cardiovascular risk as it pertains to this study relates to the initial cardiovascular diagnoses. Further research will be required to determine the risk of developing subsequent cardiovascular diseases with each drinking pattern over longer periods of time. Future research into the relationship between alcohol consumption and cardiovascular risk would benefit from further delineating cardiovascular diseases (e.g. distinguishing between thrombotic and embolic ischemic stroke), further exploring drinking patterns (i.e. assessing the spacing of drinks throughout specified time periods), investigating the impact of drink type, diet, and exercise on cardiovascular outcomes, and examining the effect of intervention (i.e. switching from high- to low-risk drinking habits) on cardiovascular risk.
Written By: Raishard Haynes, MBS