DOWN'S SYNDROME AND ALZHEIMER'S DISEASE
A Guide For Carers

by Richard Marler and Cliff Cunnngham

Richard Marler is a social worker with a special interest in adults with a learning disability. Experience with many families led him to embark on research about how carers cope with ageing and, in particular, the onset of Alzheimer's disease in Down's syndrome. (1) He carried out in-depth interviews with some 50 family members, care staff, and other professionals involved with people with Down's syndrome who had developed symptoms of Alzheimer's disease. The results clearly showed the need for accessible information for carers about the connection between Down's syndrome and Alzheimer's disease.

Cliff Cunningham has had a long interest in Down's syndrome, particularly the needs of families and care staff for accurate information, and advice on helping to promote the best quality of life for individuals and their families. (2)

They have collaborated with the Down's Syndrome Association to produce this article, which provides information about the connection between Down's syndrome and Alzheimer's disease. It is intended to support carers, after their initial reactions, to be in a better position to respond positively to the new and changing needs of the person with Down's syndrome. In particular, it deals with the questions:

• What is known about the connection between Down's syndrome and Alzheimer's disease?
• What are the risks of an individual getting the condition and when is it likely to happen?
• How is a diagnosis made and what are the symptoms?
• How can an individual be helped?
• Where can support services be found?

Cameos of real life situations have been included to illustrate the facts being presented. It is hoped that the information will help families, care staff, and other professionals cope more effectively in such circumstances, and so maintain the best quality of life for the person with Down's syndrome.

Introduction

People with Down's syndrome generally live longer and enjoy more independent lifestyles than previously. However, longer life can bring problems as well as advantages. One of the problems of old age can be Alzheimer's disease. Although the majority remain unaffected, some people with Down's syndrome seem to experience early ageing, and develop symptoms of Alzheimer's disease in middle age. This is sometimes overlooked because of their learning difficulties and other problems. Even when Alzheimer's disease is diagnosed, carers frequently find it difficult to get the support and information needed to help them cope with the additional problems.

Clearly, learning that someone we care for has a serious condition is a shock. We all want to know why. How could it happen? What can we do now? Without some answers to these questions we feel hopeless, are likely to become demoralised, and the constant anxiety of not knowing can drain our energy. When someone with a disability like Down's syndrome has additional problems, such feelings can be accentuated.

The sister of a 54-year-old woman with Down's syndrome put it this way: "I never asked 'why?' when my father got cancer. But I did ask: 'why Alzheimer's disease on top of Down's syndrome?'". The mother of a 42-year-old man affected by Alzheimer's disease pointed out: "With an older person it's expected, with a younger person it's harder to accept".

Families and care staff have considerable emotional and practical difficulties to face. Moreover, people with Down's syndrome who develop the symptoms of Alzheimer's disease do not always fit into the pattern of services available, and this can pose additional problems.

A community nurse described her experience of working with a middle-aged woman with Down's syndrome and Alzheimer's disease like this: "I felt so inadequate. I had to wheel and deal to get any service at all for my client. If I felt helpless, I can imagine how it must have felt for her family".

Carers are faced with an enormous adjustment in their approach to the individual affected, before they can begin to set about things positively. Shock, sadness, and a flood of other emotions constitute a normal reaction when such a diagnosis is suggested, and carers may experience a period of bereavement before being able to move forward.

The parent of a man in early middle age affected by the condition commented: "When they first told me .... all those years of striving to make him independent and give him some sort of life .... just seemed to have been fruitless. It was just like the beginning when they told me he had Down's syndrome. But things are better now. I have had to change my ideas for him .... he still enjoys things .... I have learnt lots of little practical things to do to keep us going."

Current knowledge

The connection between Down's syndrome and premature ageing has been known for a very long time. It is a sad but interesting story dating back to the first report in 1876 of a "mongol" whose early death was ascribed to a sort of "precipitated senility". (3). In 1907, Alois Alzheimer, a German neurologist, described the brain changes characteristic of the disease which now bears his name and accounts for a large proportion of the dementias in the general population.

It was not until 1948, however, that premature ageing in Down's syndrome was directly linked to Alzheimer's disease. (4) More recent research has confirmed that people with Down's syndrome are vulnerable to the development of the senile plaques and neurofibrillary tangles in the brain which are typical features of Alzheimer's disease. These plaques and tangles are made up of dead and dying brain tissue, and they cause the memory loss, confusion, and behavioural change, which are characteristic of this form of dementia. (5)

A further finding from research has been that all people with Down's syndrome over about the age of 40 develop the typical neuropathology (the plaques and tangles) of Alzheimer's disease but, for reasons not yet fully understood, only a proportion go on to have the disease.

That is, whilst postmortem examinations of the brains of older people with Down's syndrome always show the damage caused by Alzheimer's disease, the associated behavioural changes do not always become apparent in their lifetime. Indeed, it is important to remember that the majority will remain unaffected. This is despite increasing evidence that people over 50 years of age are particularly vulnerable. (7) The risks for individuals with Down's syndrome of developing Alzheimer's disease are discussed in more detail below.

Research in recent years has established that there is a genetic link between one type of Alzheimer's disease and chromosome 21. Since people with Down's syndrome have an extra chromosome 21, this may explain their particular vulnerability to developing this form of dementia. (8) It appears that a tiny genetic defect on chromosome 21 causes the build-up of amyloid deposits in the brain. These deposits in turn create the accumulation of dead and dying cells in the form of plaques and tangles, which cause the loss of abilities of the person affected.

The research on people with Down's syndrome has contributed greatly to this advance in knowledge about Alzheimer's disease, and it is hoped that in the future this group of doubly affected people will reap the benefits. Despite some excitement in research circles that one day genetic manipulation will become possible, and ways will be found to prevent the destruction of brain cells, the reality is that there is as yet no known treatment.

Incidence

The first point to make, when considering incidence, is the remarkable change in the life expectancy of people with Down's syndrome in recent years. It is well known that people with Down's syndrome have an increased vulnerability to various illnesses including heart disease, respiratory infections, and immunodeficiency. However, the advances made in antibiotics, open-heart surgery, immunisation programmes, and better general standards of treatment and care, have had a major impact on life expectancy.

Whereas the average life expectancy of people with Down's syndrome in 1929 was only 9 years, a recent study has suggested that over 70% are now surviving to their 30s, with 44% reaching age 60 years and 13% living to 68 years. (9)

Although the good news is that people with Down's syndrome are living longer, the bad news is that a proportion are succumbing to Alzheimer's disease in mid-life. There are no national statistics on the incidence of those developing the condition, and we have to turn again to the findings of research studies. Here, however, the story is not at all clear. Although most studies report a lower competence in older people with Down's syndrome, some show no or low incidence of Alzheimer-type symptoms, whilst others report a high incidence.

For example, a study on a large group of people with Down's syndrome living in a big mental handicap hospital in the West of England found that although 39% had deteriorated in mental age, many in a severe way, none had lost self-care skills or shown symptoms of dementia. (10) By contrast an American study on a large institutionalised group of people with Down's syndrome found that 45% of those aged 45 or over had full Alzheimer's disease symptom. (11) Other more recent American and British studies have suggested similarly high rates for people with Down's syndrome living in the community. (12,13) A study of all people with Down's syndrome living in Leicestershire found that the average age of onset of Alzheimer's disease was 54 years. (7)

The confusion over the incidence of Alzheimer's disease in the Down's syndrome population is not easily explained. There is a lack of reliable tests at present, which makes it difficult to diagnose the condition in people with learning difficulties. Also people with Down's syndrome may be affected by other impairments as they get older (e.g. deterioration in vision, hearing, or mobility). These can mask the early signs of Alzheimer's disease.

Thus, the research studies and our own experience suggest that as people live longer, an increasing number of mainly over 50 year olds are affected by Alzheimer's disease. However, even the most pessimistic findings indicate that less than half the middle-aged Down's syndrome population is implicated, so the majority appears to remain unaffected. It may turn out that the same percentage of people with Down's syndrome become affected by Alzheimer's disease as in the general population, but from a much earlier age.

In conclusion, despite the universal presence of Alzheimer's disease neuropathology, only a proportion of people with Down's syndrome develop the condition. We personally know many people in their 50s and 60s who show no symptoms whatsoever, and who are leading full and active lives.

Real life situations

Three cameos presented here illustrate the kind of situations faced by people with Down's syndrome affected by Alzheimer's disease. Although they are real life situations, names have been changed to preserve privacy. Symptoms and living situations are described in broad terms. A later section looks at how services responded to the needs of these particular individuals and their carers.

Nancy

Nancy is a 61-year-old woman with Down's syndrome living with her older sister, Theresa, who had made a promise to their mother before her death not to let Nancy go into residential care. Nancy was always an easy person to live with - sociable, friendly, and helpful around the house. About two years ago, another sister who lives nearby noticed that Nancy was becoming quieter, less lively, with less sparkle to her personality. Both sisters put it down to Nancy's getting older. Then out of the blue, she had an epileptic fit. Tests followed, and a tentative diagnosis of Alzheimer's disease was made. It came as a big shock to the sisters, who were vaguely aware that people with Down's syndrome had shorter life expectancies, but were ignorant of the connection with Alzheimer's disease.

Since then, although good days follow bad, the general picture is one of decline. Her sisters refer to the "AD curtain" coming down. When this happens Nancy cries a lot, gets frustrated, and pushes people away when she does not want to do something. She wanders aimlessly from place to place, talking to the carpet or imaginary people in the garden. She has lost some of her washing, dressing, and eating skills, and has become less mobile. Theresa, who has arthritis, is often exhausted by the physical and emotional demands of caring for her sister. With support, however, she is determined to continue caring for Nancy.

Charles

Charles is a 42-year-old man with Down's syndrome who, until recently, was living in a social services hostel several miles away from where his parents live. He had a relatively independent lifestyle going out to pubs, swimming pools, and football grounds, on his own and indulging in his love for photography. He suffered from alopecia (hair loss) at an early age, but has coped well with taunts of "baldy" from local children.

About three years ago, some concern was expressed about his tiredness and the fact that he would fall asleep sometimes at the workshop he attended. Staff in the hostel, however, were so confident in his abilities that he was moved to a training flat within the hostel to prepare for independence in the community. He had his own furniture there and for a time was very happy. Then he began to come home to his parents with strange stories about people trying to get him into their cars in the middle of the night. He started wandering off from the workshop, giving further cause for concern.

The news of the opening of a new hostel near his parents' home seemed to offer the answer to the problem of his parents keeping a closer eye on him, and Charles wanted to apply. He started to attend a different day centre, near the new hostel, where he was happy, but got confused about the journey from the old hostel. His parents decided that it would be best if he came home to live with them until the new hostel was ready. However, at home he became more and more withdrawn and irrational. One of his chores was laying the table, which he could always do perfectly for any number of people, and for any meal. He started to get up in the middle of the night to do this.

Eventually he moved into the hostel, but on the first weekend, he attacked another resident and wrecked the lounge. Prior to this, the most violent thing he had ever done was to slam a door. He was treated for depression without success and finally, after a brain scan, Alzheimer's disease was diagnosed by the local consultant in learning disability.

Although shocked by the diagnosis, his parents and a wide circle of friends continued to love and support him.

Frank

Fourteen years ago, shortly before his mother's death, Frank moved into a community house run by a voluntary organisation. He had been the sole carer of his elderly, failing mother and was seen by the professionals involved as a very good one. He surprised those who had fixed images of people with Down's syndrome by being very articulate and very capable. He independently used a bus to get from his house to the organisation's craft workshop daily, accompanying a less able resident. At the workshop he designed and made rugs to a highly skilled level.

About five years ago, at the age of 49, he began to forget people's names and became more absent-minded generally. This was followed by a period of slowing down and some unusual incidents, such as changing the sheets on his bed three times on a Saturday instead of once. Ever polite, he asked his carers: "Could you please tell me what's wrong with me?".

Then two years ago he suffered a major fit for the first time in his life, and simultaneously what appeared to be a stroke. There was a massive deterioration after that. He became less mobile, less communicative, and lost his writing ability and some self-care skills. He went on to have fits and minor strokes, losing a bit more ability each time. He continued to attend the workshop, but increasingly for social reasons, as designing rug patterns dwindled to doodling and eventually scribbling on his clothes.

Then Frank began to have hallucinations and to see dogs on the ceiling of his bedroom, and flamingoes. He stood on one leg himself for a while. He no longer recognised the house as his home and at times thought his mum was alive or, more distressingly, had just died. "I'd like to go home now please", he would say. He went on to become less polite and, out of character, somewhat aggressive. His GP, recognising the symptoms of Alzheimer's disease, began to mobilise support for Frank and his carers who were committed to maintaining him in the home he had lived in for 14 years.

Diagnosis

A confirmed diagnosis of Alzheimer's disease can only be made on postmortem examination of brain tissue. As people get older, problems with sight and hearing can also occur, and may affect a person's behaviour and confidence. Other conditions such as depression and hypothyroidism can cause similar symptoms to Alzheimer's disease. Since these are treatable, it is vitally important to have a full medical assessment at an early stage.

After other disorders are excluded by the medical profession, changes in the individual's abilities and behaviour will be considered to see if they are consistent with symptoms of Alzheimer's disease. Sometimes a brain scan is suggested, as in Charles's case, to see if there has been cortical atrophy (shrinkage of areas within the brain), although this will be only one factor in coming to a tentative decision. A GP may suggest the involvement of a consultant in learning disability or a psychogeriatrician when considering a diagnosis.

Studies on Down's syndrome and Alzheimer's disease suggest that, despite individual differences, people with Down's syndrome who have this sort of dementia show similar symptoms and stages to other people with Alzheimer's disease, although they may appear different because of the additional learning disability and other difficulties.

The common early symptoms are:

• loss of interest in activities
• short-term memory loss
• withdrawal of spontaneous communication
• loss of amenability and sociability
• loss of domestic skills
• increase in wandering
• loss of road sense
• problems in unfamiliar places
• epileptic fits
• loss of comprehension
• confusion/disorientation

There may be very gradual changes which are not recognised until after a dramatic event. In Frank's case, incidents such as changing the sheets of his bed three times on the same day served to highlight his loss of short-term memory. In another case, we were told of an incident when a woman with Down's syndrome had put on five pairs of pants because she kept forgetting she had already put some on.

In the early stages, personality change may happen gradually and be more easily noticed by those who are not in daily contact (as in Nancy's case). In other cases personality change can seem to happen suddenly. Holidays have been reported as absolute disasters in the early stages, the person with Down's syndrome becoming disoriented in the unfamiliar surroundings and alterations of routines. This is often accompanied by a change of mood characterised by sullenness, stubbornness, and obstructiveness. As one parent put it: "We left our old Trish in Blackpool".

Any changes in behaviour are particularly important to note. This may be surprisingly difficult, especially if the person is experiencing a lot of other changes in his or her life (e.g. moving to a group home, a change in family circumstances, or a key member of staff leaving). In Charles's case, he had experienced considerable changes in his living and working situations, including altered patterns of contact with his family and friends. Such changes may produce disturbed behaviour in some people with Down's syndrome, even if they do not have Alzheimer's disease, but the uncharacteristic difference in behaviour is likely to continue longer for those with the condition.

As in Frank's and Nancy's situations, epilepsy can often be a feature and this may require treatment with anti-convulsants. Symptoms can appear at any stage, but those particularly noticeable in the later stages of Alzheimer's disease include the following:

• loss of personal care skills
• loss of mobility
• episodes of depression
• hallucinations
• delusions
• irrational fears
• screaming
• incontinence
• verbal aggression
• physical aggression

Although everyone with Alzheimer's disease shares common symptoms and stages, all follow their own individual path through the condition. This is the same for those with Down's syndrome. They will progressively lose skills and abilities, some at a slow pace, others at a fast one, whilst yet others will experience plateaus (periods when their symptoms remain stable). This creates some unpredictability which can make it difficult for carers to plan how they are going to respond and cope.

References

1. R Marler (1992) Unpublished. The service needs of people with Down's syndrome who develop Alzheimer's disease. University of Portsmouth, MSc research thesis.
2. C Cunningham (1985) Down's syndrome: an introduction for parents. Souvenir Press: London. (2nd edition).
3. J Fraser and A Mitchell (1876) Kalmuc idiocy: report of a case with autopsy with notes on 62 cases. Journal of Mental Science, vol.22, p161-169.
4. G Jervis (1948) Early senile dementia in mogoloid idiocy. Americal Journal of Psychiatry, vol.105 2, p102-6.
5. C Oliver and A Holland (1986) Down's syndrome and Alzheimer's disease: a review. Psychological Medicine vol.16, p307-322.
6. D Mann (1988) Alzheimer's disease and Down's syndrome. Histopathology vol.13, p125-137.
7. R Collacott, S Cooper and C McGrother (1992). Differential rates of psychiatric disorders in adults with Down's syndrome compared with other mentally handicapped adults. British Journal of Psychiatry vol161, p671-674
8. C Wischik (1989) The relationship between Alzheimer's disease and Down's syndrome. In Eds V Cowie and V Harten-Ash, Current Approaches: mental retardation, p1-11. Duphar press: Southampton.
9. P Baird and A Sadovnik (1988) Life expectancy in Down's syndrome adults. Lancet, p1354-6.
10. K Hewitt (1985) Psychological aspects of ageing in Down's syndrome. Mencap: Taunton.
11. M Thase, L Liss, D Smeltzer and J Maloon (1982) Clinical evaluation of dementia in Down's syndrome: a preliminary report. Journal of Mental Deficiency Reesearch vol.26, p239-244.
12. W Muir, I Squire, D Blackwood, M Speight, D St Clair, C Oliver and P Dickens (1988). Auditory P300 response in the assessment of Alzheimer's disease in Down's syndrome: a 2 year follow-up study. Journal of Mental Deficiency Research vol.32, p455-463.
13. F Lai and R Williams (1989) A prospective study of Alzheimer's disease in Down's syndrome. Archives of Neurology vol.46, Aug, p849-853.