A stroke damages part of the brain because the blood flow is interrupted. The medical term for stroke is apoplexy. A stroke can have many different consequences.
The symptoms particularly depend on which part of the brain is affected. The following are common signs of a stroke: sudden weakness, numbness and signs of paralysis, speech problems, trouble seeing, dizziness and difficulty walking, severe headache.
There are two main causes of a stroke. They are most frequently caused by a blood clot that is blocking a blood vessel in the brain. These clots can form in the brain itself, for example because of changes in the artery wall caused by infection. However, they occur more often in another part of the body and are carried into the brain along the bloodstream, where they then block a blood vessel. A stroke that is caused by a blocked blood vessel is referred to as an ischemic stroke.
Bleeding (hemorrhage) in the brain is the second, less common cause. This can occur because a blood vessel ruptures and blood leaks into the brain tissue.
In both cases, part of the brain is temporarily or permanently no longer supplied with enough oxygen. The sooner oxygen supply is restored, the better the chances are of keeping damage to a minimum.
It is very uncommon for blood clots to develop in the blood vessels of healthy people. But certain illnesses and genetic factors can increase the risk of a stroke. They include high blood pressure and long term atrial fibrillation.
It is possible that the typical symptoms of a stroke go away by themselves after a few hours. This could be a "transient ischemic attack" (TIA), where a blood clot had formed and then went away again before the brain was damaged more severely. A TIA is however an indication of an increased risk of a stroke.
Prevalence and outlook
Around one out of 1,000 people has a stroke in their lifetime. The risk increases with age: Around 20 out of 1,000 people aged over 85 are affected.
Most people survive a stroke. But strokes can cause paralysis in certain parts of the body or problems with various bodily functions, for example speech.
Symptoms such as paralysis often get better over time, but they can also be permanent. Psychological problems like depression are therefore not uncommon.
People who have had a stroke are also at greater risk of having another one. Around 40 out of 100 people who survive an ischemic stroke have another stroke within ten years.
The risk is particularly high within the first six months. But people who have had a stroke are also more likely to have other cardiovascular diseases such as a heart attack.
Somebody having a stroke requires urgent medical attention. If you think you or somebody else might be having a stroke you should call for an ambulance immediately (112 in Germany; 911 in the U.S.). Do not wait to see if the symptoms go away.
After the paramedics have provided first aid, the patient will be taken to a hospital that specializes in the diagnosis and treatment of strokes, as long as it is not too far away. The patient is then thoroughly examined to find out the cause of the symptoms. That includes CT or MRI scans.
Whether particular preventive measures against a stroke are worthwhile depends on any other conditions and risk factors that someone might have.
Doctors will usually suggest preventive measures after precisely examining people who have already had a transient ischemic attack or even a stroke.
People with high blood pressure can reduce their risk of a stroke by taking blood-pressure lowering medication. If somebody has an increased risk of blood clots, for example due to long term atrial fibrillation, anticoagulant (anti-clotting) medication can be an option.
Acute treatment aims to save a person's life and minimize the damage of the stroke as much as possible. The type of treatment mainly depends on whether the stroke was caused by a blood clot or a hemorrhage.
If it was caused by a blood clot, the doctors generally try to dissolve it as quickly as possible using medication or a catheter. Brain hemorrhages have to be stopped quickly, where necessary by operating.
Further treatment and observation then depends on the severity of the stroke, the type of symptoms afterwards, and the results of further examinations.
It is often very important for people to regain their mobility, muscle strength, speech, and independence after having a stroke. It is also important to restore emotional balance.
There are various rehabilitation programs with different contents. Different therapists prefer different treatments, and there are also differences from country to country.
The main elements of rehabilitation include speech therapy, physiotherapy and fitness training to try and minimize any physical disabilities and learn to deal with them. Rehabilitation also includes occupational therapy, where patients learn how they can go about their daily lives as independently as possible despite any restrictions.
It is normal to feel sad and depressed after a stroke. Depending on the severity of the stroke, it can considerably restrict a patient's life.
People who lived independently before and are then dependent on others for help first have to learn to come to terms with the effects of the stroke, both the physical consequences as well as in practical everyday situations.
That is why therapy can help people to regain some of their independence after a stroke. Over time, most patients and their families manage to adapt their lives to the changes.
However, as a result of a stroke some people develop depression that requires treatment from trained professionals. If the depression lasts for a long time it can affect a patient's overall health. These kinds of depression often go unnoticed, or sadness and feeling down is considered to be a normal reaction and no steps are taken to treat it.
It is not always easy to differentiate between deep sadness and depression after a stroke. It is important that patients and their families receive the support that they need to prevent depression, or are offered help if depression has already set in.
There is lots of support available for people who have had a stroke and their families. That includes counseling centers and self-help groups that can provide patients and their families with help about care, finances and psychosocial issues.
Lots of cities and municipalities provide care counseling centers free of charge.
Family members can also take part in care courses to learn basic care techniques.
What is on offer depends on the center and cannot always be found immediately. That is why we have put together a list of places that you can contact to find out where you can get help in your local area.
Brereton L, Carroll C, Barnston S. Interventions for adult family carers of people who have had a stroke: a systematic review. Clin Rehabil 2007; 21: 867-884.
Hackett ML, Yang M, Anderson CS, Horrocks JA, House A. Pharmaceutical interventions for emotionalism after stroke. Cochrane Database Systematic Reviews 2010, Feb.
Hackett ML, Yapa C, Parag V, Anderson CS. Frequency of depression after stroke. A systematic review of observational studies. Stroke 2005; 36; 1330-1340.
McPherson K, Kersten P, Turner-Stokes L. Background to neurorehabilitation. In Candelise L et al (eds). Evidence-based neurology. London: BMJ Books. 2007.
Forster A, Brown L, Smith J, House A, Knapp P et al. Information provision for stroke patients and their caregivers. Cochrane Database of Systematic Reviews 2012, Issue 11.
Warburton E. Stroke management. Clinical Evidence. 2007; 04: 201
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