Chapter 2 - What is Stroke?

Key Points

  • Stroke accounts for 10% of all deaths
  • Stroke affects 150,000 people in the UK, killing 53,000, each year
  • Stroke-related costs in the UK NHS amount to £2.8 billion
  • Surviving a stroke is frequently reported to be 'worse than death'
  • Stroke is a leading cause of adult disability
  • The consequences of stroke are dramatic and can negatively impact many people beyond the stroke victim

The brain requires a constant supply of blood for it to receive essential oxygen and nutrients.  A stroke happens when the blood supply to any part of the brain is cut off and brain tissue is damaged.

The impact of a stroke is both instant and unpredictable.  The nature and the severity of the effects depend on the amount of damage caused and the part of the brain that has been affected.  Frequently people become paralysed, numb or incapable of normal speech.  Vision can be impaired, as can both thoughts and feelings.

Stroke accounts for 10% of all deaths,43,56 and is also a leading cause of adult disability.3,38  The sudden nature of stroke means that sufferers, families and carers have no opportunity to prepare for what is usually a tremendous blow to their lives.

Beyond the personal impact of death and disability, stroke costs us all through the massive burden it places on National Health Service (NHS) budgets and the impact it has on the wider economy.  It is estimated that the direct cost of stroke to the NHS is £2.8 billion, and that stroke patients occupy up to a quarter of all hospital beds.3

Effective methods to prevent stroke in people at high risk are both widely available and inexpensive.  The potential exists to save thousands of lives and millions from healthcare budgets.

What causes a stroke?

The vast majority, around 85%, of strokes are caused by a blockage in one of the blood vessels that supplies the brain.56  The remaining 15% are usually the result of a bleed.  Strokes caused by blockages are called ischaemic (ISS-KEEM-IC).  Ischaemic is a medical term denoting a lack of oxygen.  The most common cause of ischaemic strokes is a blockage caused by a blood clot.  Most ischaemic strokes are the result of an embolism, which is a clot, or other material, that travelled to the brain in the bloodstream from somewhere else.  For example, a blockage caused by a clot that formed in the heart is a cardioembolic ischaemic stroke.  Strokes caused by bleeds are called haemorrhagic (HEM-UH-RA-JIC).

What’s a mini-stroke or TIA?

If the blood supply to the brain is only briefly interrupted a mini-stroke might result.  Also known as a transient ischaemic attack or TIA.  The symptoms of a TIA are very similar to those of a stroke but last fewer than 24 hours.  It is vital that medical attention is sought regardless of the temporary effects; individuals who have had a TIA are at high risk of suffering a stroke.  Studies have shown that in the 90 days following a TIA, the risk of stroke exceeds 10%.39

How many people does stroke affect?

Worldwide, stroke is the most common cardio-vascular disorder after heart disease, accounting for 5.7 million deaths annually, nearly one in ten of all deaths.43 In the UK, 150,000 people are struck by stroke each year,1 and 53,000 people are killed.40  This makes stroke the third biggest killer in the UK after heart attacks and cancer.41Stroke accounts for 9% of all deaths among UK men and 13% among UK women.42

For many, surviving a stroke is a fate worse than death; stroke is the leading cause of adult disability.  Over 300,000 people in the UK are living with permanent disabilities as a result of suffering a stroke.3

The total number of people living through the consequences of stroke in Europe has been estimated to be 9.6 million.43  A World Health Organization (WHO) study reported that the annual number of new cases in Europe to be two million in 2004.43 This was comparable to the estimated annual incidence of cancer cases at 2.9 million for the same year.44

For countries within the EU, a study based on data from WHO estimated the number of strokes to be 1.1 million in 2000.69  Furthermore, it has been predicted that stroke incidence will increase to 1.5 million per year by 2025, largely owing to the increasing proportion of elderly individuals.69

The below charts illustrate authoritative estimates of stroke incidence throughout Europe.  It is immediately apparent from the first chart that some countries face a greater challenge than others and that, Europe-wide, men are generally affected more than women.  It is also clear that the UK has a long way to go if we are to reduce the rate of stokes to levels currently observed in France and Switzerland.  Unless we act now to prevent avoidable strokes in AF patients, this task will become immeasurably more difficult.

Comparing stroke rates in Europe69.  Click to enlarge.

This second chart shows the same data by age.  While it is clear that stroke is most commonly an affliction of the elderly, there are many countries within which a disproportionate number of those affected by stroke are aged 55-74.

The risk of stroke generally increases with age69. Click to enlarge.

Who suffers from stroke

While predominantly affecting the elderly, approximately 25% of strokes occur in people aged below 65 years.22  In the UK, it has been estimated that 20,000 strokes occur in those who are 45 and younger every year.

Several risk factors other than age contribute significantly to stroke risk.  Principal among them are atrial fibrillation, heart failure, heart disease and high blood pressure.  Atrial fibrillation has the most powerful impact, elevating risk over a non-AF patient by five times.  AF is directly responsible for 20% of strokes.  High blood pressure on its own elevates the risk less than each of the other three main risk factors, but because so many people have high blood pressure, it represents the single biggest cause of stroke in the UK.

Lifestyle factors also play an important role.  Smoking has been shown to double a person’s risk of suffering a stroke.  Poor diet, lack of exercise and excessive alcohol intake have also been shown to increase stroke risk.

Some ethnic differences may also exist, reflecting differences in the predisposition to some of the risk factors associated with stroke.  For example, there is a high prevalence of high blood pressure and, as a consequence, stroke, among afro-caribbean populations.  In the UK, the death rate from stroke has also been found to be higher among individuals of south asian origin than among the caucasian population.45

What are the consequences of stroke?

As well as accounting for nearly 10% of all deaths43 56, stroke is a major cause of long-term disability.  Worldwide, five million stroke sufferers are left permanently disabled every year.56  In the UK, over 300,000 stroke survivors are living with permanent disabilities which leave them dependent upon others.  Stroke can affect nearly all human functions, making it difficult for many patients to get out of bed, walk short distances or perform the basic activities of daily living.  As well as impairing speech and physical functioning,56 stroke can also adversely affect mental health.46 

Strokes are sudden and they frequently affect people who were unaware they were at risk.  Consequently, they and their families are often poorly prepared to deal with the stroke and the damage it brings to their lives.46  Long-term disability can dramatically affect the quality of life of both patient and relatives.  

Not only does the patient and his or her family frequently have to shoulder the burden of an unexpected long-term disability, those living with the aftermath of a stroke are often in constant fear of death or another stroke

The consequences of stroke are far from limited to the elderly.  A long-term study assessing outcomes in young adults (aged 15–45) after a stroke found that within six years only 49% were still alive, not disabled, had not suffered from a recurrent event or had not undergone major vascular surgery.  The majority of the survivors also reported emotional, social or physical effects that reduced their quality of life.47

What are the costs of stroke?

Not only are strokes tragic, fatal and debilitating, they are extremely expensive.  It has been estimated that a single stroke costs the NHS between £9,500 and £14,000.  The factors that cause a stroke have been found to have a bearing on the severity of a stroke.  For example, people with AF tend to have more severe strokes which are consequently more expensive.48 62

Strokes cost more than their direct burden on healthcare budgets.  The wider economy suffers from the loss of productivity associated with disability and death.  The long-term care required for stroke survivors is usually informal and often overlooked.  Yet this also comes with a tremendous cost to society.  Then there is the human cost, which is incalculable.

Our NHS hospitals are also burdened with providing the physical space required to treat stroke patients. Stroke survivors occupy around 20% of all acute hospital beds and one quarter of all of long-term beds3

The direct cost of stroke to the NHS has been estimated to be £2.8 billion every year.  This huge sum, however, does not represent even half of the total costs.  The indirect costs to the wider economy are £1.8 billion and the costs of informal post-stroke care amount to an estimated £2.4 billion.3

If just the avoidable strokes arising because of AF were prevented, the NHS would save nearly £60 million in direct stroke costs alone.  In the chart below, the cost of stroke to the UK can clearly be seen.  Both the total of stroke costs and the cost per head of population are among the highest spent of any country in Europe.

The cost of stroke for the whole of the EU was calculated to be over €38 billion in 2006. This figure included healthcare costs (about 49% of the total), productivity loss due to disability and death (23% of the total) and informal care costs (29% of the total).57  These figures demonstrate the tremendous financial burden to society posed by stroke in Europe.

It is clear that stroke is a costly health problem in the UK and beyond.  Stroke accounts for a massive burden on patients, their carers, families, friends and society.  This burden falls disproportionately on the elderly, who are most at risk.  Early diagnosis and effective management of atrial fibrillation would help to reduce the burden of stroke in the UK.  Furthermore, the prevention of stroke with existing, cost-effective therapies in patients at high risk has the potential to reduce this huge economic burden significantly.50 

For example, in patients with AF, who are known to have a high risk of stroke, the cost of treating a stroke has been calculated to be almost four times greater than the cost of prevention with ten years’ anticlotting therapy.97

Stroke is a massive expense for the NHS and the taxpayer. Click to enlarge.