Stroke

What is a stroke?

Another term for stroke is cerebrovascular accident (CVA), a blockage or rupture of a blood vessel in the brain resulting in brain damage. A stroke can take three forms:

1. In a cerebral infarction, a blood clot or vascular constriction closes off a blood vessel in the brain. As a result, part of the brain is deprived of oxygen and dies off. A cerebral infarction with symptoms that last for less than 24 hours is known a transient ischaemic attack (TIA). The sudden losses of function in a TIA are the result of a temporary disruption of circulation in a part of the brain. Functions return when the blood supply recovers. About 75% of strokes result from cerebral infarction, including TIAs.
2. In a cerebral haemorrhage, a blood vessel with a thin or rigid vessel wall ruptures and blood flows into a part of the brain. About 15% of strokes involve a ruptured blood vessel in or around the brain.
3. In a subarachnoid haemorrhage, the haemorrhage is located in the space between the meninges, just below the skull. This accounts for about 5% of strokes.

A small proportion of strokes (5%) are caused by rare abnormalities and they are classified as 'other strokes'.

Strokes are usually caused by poor blood-vessel quality, which is generally due to age (arteriosclerosis), smoking, diabetes, high blood pressure or raised cholesterol levels.

What are the complaints associated with a stroke?

A stroke produces sudden-onset symptoms. These may include: facial paralysis (a skewed mouth, for example), loss of visual field, confused speech and thinking, swallowing problems, incontinence, arm or leg paralysis, loss of vision and tingling. A cerebral haemorrhage may also be accompanied by severe headache or drowsiness. Common long-term consequences are character changes and changes in emotions. ¹⁴¹

How common is stroke in the general population?

The one-year prevalence for stroke is about 1.34%.  ¹⁴⁰

Stroke is the second most common cause of death for women and the third for men. The prevalence of stroke has increased in recent years due to the ageing of the population, while the incidence has remained stable. The current incidence rate (without TIAs) is 2 to 3 per 1000 people a year. The incidence of stroke increases significantly with age: the annual incidence rate in the age group 15 to 64 is 1 per 1000, increasing to 10 to 11 per 1000 in the age group over 65. About 80% of cases are cerebral infarction, with the other cases resulting from intracerebral haemorrhage. ¹⁴¹

A study by the Dutch National Institute of Public Health and the Environment (RIVM) found an annual incidence rate in the group of 50 years and older of 4 per 1000. ¹⁴⁰

How common is stroke in people with intellectual disabilities?

The European POMONA questionnaire survey of a random sample of 1269 adults with intellectual disabilities found a prevalence rate for stroke of 1.5%. ¹⁴²

A three-year follow-up study to the Dutch GOUD study found an annual incidence rate for stroke in people with intellectual disabilities aged 50 years and older of 4 per 1000, which is exactly the same as the rate for the general population. ⁴⁹⁰

This finding confirmed a previous Dutch file study. ⁴⁹¹

There are indications that stroke occurs more frequently in people with Williams syndrome. ^{143   492}