|
| health information | health news
Hot topic - Heavy drinking linked to increased stroke risk
11 January 2005 - written by Bupa's Health information team
Men who drink more than the daily recommendations of alcohol may be more likely to suffer from a stroke, according to a new US study published in the 4 January 2005 edition of the Annals of Internal Medicine.1
What did the study show?
The study showed that men who drank three or more alcoholic drinks a day (more than three units) may be nearly 45 percent more likely to suffer from a stroke compared with non-drinkers.
However, moderate drinkers - who drank one or two alcoholic drinks (one to three units) on three to four days of the week - had an average 32 percent lower risk of stroke than non-drinkers.1
Who took part in the study?
The study included 38,156 men aged between 40 and 75 years of age. None of the men had ever had a stroke.1
How was the study carried out?
The men filled out questionnaires every four years for a total of 12 years. They answered questions about how much alcohol they drank, what types and how often. They were also asked if they'd had a stroke since the last questionnaire.1
What is a stroke?
A stroke is a type of brain injury. When a person suffers a stroke, the blood supply to a part of the brain is suddenly cut off. This means that the brain cells don't get enough oxygen. When this happens, the cells in this part of the brain become damaged or die.
Every stroke is different and people who have strokes are affected in different ways, depending on how severe the stroke is and which part of the brain is affected.2,3
What causes a stroke?
A stroke is most commonly caused by a blood clot in an artery which blocks the flow of blood to the brain. But it can also result from a damaged blood vessel causing bleeding into the brain.2
Some strokes can occur for no reason at all. But there are known factors that may make you more likely to suffer from a stroke, including:
- high blood pressure
- strong family history of stroke
- diabetes
- smoking
- high cholesterol
- obesity
- heart disease
- heavy alcohol consumption3
Why may heavy drinking be linked to an increased risk of stroke?
Alcohol may be linked to the risk of a stroke because heavy drinking is associated with high blood pressure and a fast, irregular heart beat.1,3
High blood pressure is the single most important risk factor for stroke. High blood pressure puts a strain on the blood vessels, which can lead to the narrowing of arteries and the formation of blood clots.3,4
A fast, irregular heart beat can cause erratic blood flow, which may lead to the formation of a blood clot. A blood clot may block the flow of blood to the brain and cause a stroke.3,5
Why may moderate drinking be linked to a decreased risk of stroke?
Research has shown that drinking moderate amounts of alcohol may protect against heart disease.3 The blood vessel disease (that can lead to formation of a blood clot) that causes a stroke is similar to that which causes heart disease. The same factors that cause or prevent heart disease often cause or prevent stroke.
In this study, the lower risk of stroke associated with moderate drinking is also linked to drinking patterns - the number of days a week that alcohol is drunk and how much is consumed on those days.1
How do drinking patterns affect the risk of stroke?
The lowest risk of stroke seems to occur when drinking alcohol is limited to one or, at most, two drinks approximately every other day. This benefit appears to be lost if alcohol is drunk on more than three to four days of the week.1
What are the daily recommendations for drinking alcohol?
The sensible drinking recommendations for adults in the UK are:
- three to four units a day for men
- two to three units a day for women6
How much is a unit of alcohol?
In the UK, one unit is equal to 8g of alcohol. As a rough guide, the following drinks contain one unit of alcohol:
- one small glass (125ml) of table wine
- a single pub measure (25ml) of whisky, gin or brandy
- half a pint of beer or cider
- quarter of a pint of superstrength beer or cider7
Are all types of alcohol linked to an increased risk of a stroke?
The study showed that men who drank red wine had a 23 percent lower risk of a stroke compared with those who drank other types of alcohol. Further research is needed to confirm this finding.1
Who suffers from strokes?
Most people who suffer from strokes are over 65 years old. But a stroke can occur at any age, even in babies.2
How common are strokes?
Each year about 110,000 people in the UK suffer from a stroke for the first time. Another 30,000 people have a further stroke. A stroke is the third biggest cause of death in the UK after heart disease and cancer.2
What are the symptoms of a stroke?
The symptoms of a stroke depend on the part of the brain that is injured. Symptoms develop very quickly and usually include one or more of the following:
- headache
- confusion
- problems with balance, co-ordination, vision or speech
- weakness of an arm or leg, or both
- weakness and twisting of one side of the face, which may cause drooling
- numbness in a part of the body
- loss of consciousness (in severe cases)2
How are strokes treated?
If you have a stroke, you are very likely to be admitted to hospital. Your treatment plan will depend on how severe your stroke is. Medicines may be given to help prevent blood clots forming in the blood vessels. This may help to prevent a further stroke.
The most important part of treatment is rehabilitation. Rehabilitation involves helping you back to good health after your stroke.2
What can I do to lower my risk of having a stroke?
Certain risk factors increase the chance of you having a stroke. You can lower your risk of a stroke if you reduce your risk factors:
- drink alcohol only in moderation - do not exceed the daily recommended units (see above)
- aim to eat a healthy balanced diet that is low in cholesterol
- keep your salt intake low (maximum of 6g a day) so that your blood pressure stays within normal limits
- don't smoke - the chemicals in cigarettes can damage your arteries and increase your risk of suffering a stroke
- take regular exercise - aim for 30 minutes of physical activity (eg brisk walking) on five or more days of the week
- try to lose some weight if you are overweight
- if you have diabetes, it is important that you keep your blood sugar as close to normal levels as possible - having diabetes increases your risk of having a stroke
- some people may be advised to take medicines that help prevent blood clots, particularly if they have already suffered a stroke2
Further information
Bupa resources:
External resources:
References
- Mukamal KJ, Ascherio A, Mittleman MA et al. Alcohol and risk for ischemic stroke in men: the role of drinking patterns and usual beverage. Ann Int Med 2005;142:11-19.
- Patient UK. Stroke.
http://www.patient.co.uk
- The Stroke Association. All about stroke.
http://www.stroke.org.uk
- Blood Pressure Association. What is high blood pressure?
http://www.bpassoc.org.uk
- Patient UK. Atrial fibrillation.
http://www.patient.co.uk
- NHS Health Development Agency. Alcohol: Facts and figures.
http://www.wiredforhealth.gov.uk
- Institute of Alcohol Studies (IAS). IAS Factsheet: Alcohol and you.
http://www.ias.org.uk
All websites accessed on 06/01/05
|