The risk of stroke appears to double an hour after consuming just one drink – whether it’s wine, beer or hard liquor. “The impact of alcohol on stroke risk appears to depend on how much and how often you drink,” said Murray A. Mittleman, MD, Dr.PH, senior author of the Stroke Onset (SOS) study and director of the Research Unit of Cardiovascular Epidemiology at Beth Israel Deaconess Medical Center at Harvard Medical School in Boston, Massachusetts. Before SOS, researchers did not know whether alcohol consumption had a direct impact on ischemic stroke (caused by a blood clot in a vessel or lead to the brain), although moderate alcohol use (less than two drinks a day) may to potentially lower risk in the long term. The researchers interviewed 390 stroke patients (209 men, 181 women) about three days after their stroke about several aspects of their lives. READ MORE: Drink enjoyed by millions in UK ‘significantly’ increases cancer risk – and it’s not alcohol The patterns remained the same whether participants consumed wine, beer or spirits. When the researchers excluded patients who had been exposed to other potential triggers (such as vigorous exercise or drinking a caffeinated beverage) just before their strokes, the association with alcohol did not change. Only one participant had consumed more than two drinks in the hour preceding the stroke, and removing these data did not change the pattern. “The evidence on heavy drinking is consistent: Both long-term and short-term it increases the risk of stroke,” said Mr. Mittleman. READ MORE: Diabetes: The red juice that can ‘fight’ diabetes by ‘continuously’ improving blood sugar “But we find that it’s more complicated with light to moderate drinking. It’s possible that the transient increased risk of stroke from moderate drinking is outweighed by the long-term health benefits.” Immediately after drinking, blood pressure rises and platelets become stickier, which can increase the chance of a clot forming. However, continued use of small amounts of alcohol is associated with beneficial changes in blood lipids and more flexible blood vessels, which may reduce risk overall. “At this point we don’t have enough evidence to say that non-drinkers should start or that people who drink small amounts – on the order of one drink a day – should stop,” Mr Mittleman said. A more conclusive answer would require a controlled study in which some people are randomly selected to drink alcohol while others are not, he said. It is important to note that the findings may not apply to patients with severe stroke.
Unchanged risk factors
It is not possible to completely prevent strokes because some things that increase the risk of the condition cannot be changed. According to the NHS, these include:
Age – you’re more likely to have a stroke if you’re over 55, although around one in four strokes happen in younger people Family history – if a close relative (parent, grandparent, brother or sister) has had a stroke, your risk is likely to be higher Ethnicity – if you are from South Asia, Africa or the Caribbean, your risk of stroke is higher, partly because rates of diabetes and high blood pressure are higher in these groups Your medical history – if you’ve had a previous stroke, transient ischemic attack (TIA) or heart attack, your risk of stroke is higher.
