Disease of the brain that impairs,
Daily activities
Worldwide, there is one new case of dementia diagnosed every seven seconds.

5% of people over 65 have dementia.

This increases to 10% after 75 years of age.


What causes dementia?

Alzheimer’s disease is the most common cause. Damaged tissue builds up in the brain to form deposits called ‘plaques’ and ‘tangles’. These cause the brain cells around them to die.Â

Alzheimer's also affects the chemicals in the brain which transmit messages from one cell to another, particularly acetylcholine. It comes on gradually and develops slowly over several years. It can sometimes run in families and it is more likely to affect people with Down’s syndrome.

Alzheimer’s disease produces particular problems with memory and thinking. Learning new information becomes harder – you can't remember recent events, appointments or phone messages.Â

You may forget the names of people or places and may struggle to understand or communicate with others. Commonly, you just can't find the right word for objects or people you know well. This can make you frustrated and depressed. You may accuse people of taking things when all that has happened is that you have lost them.

Sometimes people with dementia do not feel there is anything wrong with them and get cross when people try to help. Carers often comment that the Alzheimer’s has changed the personality, so the person behaves or reacts differently to how they did before they became ill.Â

Vascular dementia - the arteries supplying blood to the brain become blocked. This leads to small strokes - parts of the brain die as they are starved of oxygen. It is more common if if you are a smoker or if you have high blood pressure, diabetes or high cholesterol.

It is difficult to predict how fast it will deteriorate. It can be stable for several months or years but then, when more strokes happen, you get further deterioration.

The problems caused by vascular dementia will depend on which part of the brain is affected. There may be memory loss, poor concentration, word finding difficulties, mood swings or depression. Some people have hallucinations (where they see or hear something that is not there). Physical problems can develop, such as difficulties with walking or incontinence.

Lewy body dementia - People with Lewy body dementia have symptoms which overlap with Alzheimer’s disease and Parkinson’s disease. The level of confusion can vary during the course of the day, but visual hallucinations of people or animals are more common. They may also have a tremor, muscle stiffness, falls or difficulty with walking.Â

Fronto-temporal dementia – if the dementia affects the front of the brain more than other areas, it is more likely to cause personality changes as well as memory problems.

Other causes of dementia

Many other illnesses can cause memory problems. Depression can cause a 'pseudo-dementia' which can get better with antidepressants and talking therapy. Physical illnesses which cause memory problems include:

  • kidney, liver or thyroid problems
  • shortage of some vitamins (rare)
  • chest or urine infections can lead to confusion and can be treated with antibiotics
  • rarer conditions such as Huntington’s disease, which causes dementia in younger people.Â

What is mild cognitive impairment?

Many of us worry about our memory as we get older. This term is used when the problem is more than you would expect for your age but not bad enough to be called dementia.

About 1 in 20 of people with this problem may develop dementia, but we can't yet predict who these people will be.

Risk facors

Untreatable Treatable Increase riskÂ
Age Cerebrovascular disease 9×
Genetics Diabetes 2×
Gender Hypertension 2×
Head trauma Hyperlipidaemia 2×

Early diagnosis and treatment can make a differenceÂ

Screening test for Dementia

Mini Mental State Examination (MMSE)

Mini Mental State Examination gives the 'mini-mental state' examination of cognitive function. This is a 5-minute bedside test that is useful as a screen and in assessing the degree of cognitive dysfunction in patients with diffuse brain disorders. It correlates well with more time-consuming Intelligence Quotient (IQ) tests, but it will not as easily pick up cognitive problems caused by focal brain lesions. A score of 23 or less will pick up about 90% of patients with cognitive impairments, with about 10% false positives.

The mini-mental state examination

Score one point for each correct answer:

What is the: time, date, day, month, year? Maximum: 5 points

What is the name of: this ward, hospital, district, town, country? 5 points


Name three objects only once. Score up to a maximum of 3 points for each correct repetition. 3 points

Repeat the objects until the patient can repeat them accurately (in order to test recall later).

Attention and calculation

Ask the patient to subtract 7 from 100 and then 7 from the result four more times.

Score 1 point for each correct subtraction. 5 points


Ask the patient to repeat the names of the three objects learnt in the registration test. 3 points


Score 1 point for each of two simple objects named (e.g. pen and a watch). 2 points

Score 1 point for an accurate repetition of the phrase: 'No ifs, ands or buts'. 1 point

Give a 3-stage command, scoring 1 point for each part correctly carried out; e.g. 'With the index finger of your right hand touch your nose and then your left ear'. 3 points

Write 'Close your eyes' on a blank piece of paper and ask the patient to follow the written command. Score 1 point if the patient closes the eyes. 1 point

Ask the patient to write a sentence. Score 1 point if the sentence is sensible and contains a noun and a verb. 1 point

Draw a pair of intersecting pentagons with each side approximately 1 inch long. Score 1 point if it is correctly copied. 1 point


This depends on the diagnosis and your circumstances. Unfortunately there are no cures for many of these conditions.

There is a group of drugs called acetyl cholinesterase inhibitors which may slow the progression of Alzheimer’s dementia. These drugs may also help in Lewy Body dementia if hallucinations are a problem. In Vascular dementia, a small dose of aspirin may help to prevent further strokes or medication may help to control high blood pressure or raised cholesterol. It is also important to stop smoking, eat healthily and take exercise.

Who to consult / Where to get help?

Family docter
Psychiatry and Neurplogy departments in hospitals.