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Understanding mental capacity
Understanding mental capacity

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2 Who and how many lack mental capacity?

Mental capacity problems can affect many different sorts of people.

Activity 4 Who might lack mental capacity?

Timing: Allow about 5 minutes

In the text box below, make a list of people you think are most likely to lack mental capacity. Think about people you know, or have seen on television, or have read about in newspaper articles. They might lack mental capacity permanently or temporarily.

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Your list might include:

  • older people who have dementia
  • adults and children with learning disabilities
  • people who are using health and social care services
  • people with a mental health illness
  • people with eating disorders
  • people who have had a stroke
  • people with temporary loss of capacity through intoxication
  • people with brain injuries.

However, understanding mental capacity is important for all of us as any of us, and our friends and family, may lack capacity in the future.

So how many people might lack mental capacity for some decisions? You look now at the numbers of people in some of the categories listed above.

People with dementia

At the time of writing (August 2017), there were an estimated 850,000 people with dementia in the UK (Alzheimer’s Research UK, 2017). This is similar to the number of ceramic poppies that were installed in the Tower of London in 2014 to represent the number of British military fatalities in World War One.

Tower of London Poppies art installation by Cummins and Piper (2014)
Figure 1 Tower of London Poppies art installation by Cummins and Piper (2014)

See the NHS Choices page About dementia [Tip: hold Ctrl and click a link to open it in a new tab. (Hide tip)] for more information on dementia.

People with learning disabilities

It has been estimated that just over a million people in England (2% of the population) have a learning disability. The numbers known to learning disability services are much smaller: an estimated quarter of a million people. (Figures taken from Public Health England, 2015.)

People with alcohol and drug problems

More than 9 million people in England drink more than the recommended daily amount (Health and Social Care Information Centre, 2017). In 2014 there were 8,697 alcohol related deaths in the UK (Health and Social Care Information Centre, 2017). People in this group are more likely to have impaired mental capacity because of resulting mental health issues, the temporary lack of capacity when drunk and the effect that severe addiction/craving has on decision making.

People who have suffered brain injury

Brain injury can occur at any age and from a number of causes.

People with mental health needs

Mental ill-health affects people in the UK and globally. Problems range from anxiety and depression to hearing voices and psychoses.

One in 50 people suffer from bi-polar disorder, and one in 100 from psychotic disorder (NHS Digital, 2014).

People in these groups may all have reduced mental capacity. Two million people in England and Wales are estimated to lack capacity (SCIE, 2016). But who else is affected as a result?