Early stage Middle stage Late stage
The early stage is often overlooked. Relatives and friends (and sometimes professionals as well) see it as "old age", just a normal part of the ageing process. Because the onset of the disease is gradual, it is difficult to be sure exactly when it begins. The person may:
■ have problems talking properly (language problems)
■ have significant memory loss — particularly for things that have just happened
■ not know the time of day or the day of the week
■ become lost in familiar places
■ have difficulty in making decisions
■ become inactive and unmotivated
■ show mood changes, depression or anxiety
■ react unusually angrily or aggressively on occasion
■ show a loss of interest in hobbies and activities
As the disease progresses, limitations become clearer and more restricting.
The person with dementia has difficulty with day-to-day living and:
■ may become very forgetful, especially of recent events and people's names
■ can no longer manage to live alone without problems
■ needs help with personal hygiene, i.e. washing and dressing
■ has increased difficulty with speech
■ shows problems with wandering and other behaviour problems such as repeated questioning and calling out, clinging and disturbed sleeping
■ becomes lost at home as well as outside
■ may have hallucinations (seeing or hearing things that are not there)
The late stage is one of nearly total dependence and inactivity. Memory disturbances are very serious and the physical side of the disease becomes more obvious. The person may:
■ have difficulty eating
■ be incapable of communicating
■ not recognize relatives, friends and familiar objects
■ have difficulty understanding what is going on around them
■ be unable to find his or her way around in the home
■ have difficulty walking
■ have difficulty swallowing
■ have bladder and bowel incontinence
■ display inappropriate behaviour in public
■ be confined to a wheelchair or bed in this document (17) constitute the best available basis for policy-making, planning and allocation of health and welfare resources.
There is a clear and general tendency for prevalence to be somewhat lower in developing countries than in the industrialized world (18), strikingly so in some studies (19, 20). This trend was supported by the consensus judgement of the expert panel convened by Alzheimer's Disease International, reviewing all available evidence (17). It does not seem to be explained merely by differences in survival, as estimates of incidence are also much lower than those reported in developed countries (21, 22). It may be that mild dementia is underdetected in developing countries because of difficulties in establishing the criterion of social and occupational impairment. Differences in level of exposure to environmental risk factors might also have contributed. The strikingly different patterns of mortality in early life might also be implicated; older people in very poor countries are exceptional survivors — this characteristic may also confer protection against AD and other dementias.
Long-term studies from Sweden and the United States of America suggest that the age-specific prevalence of dementia has not changed over the last 30 or 40 years (23). Whatever the explanation for the current discrepancy between prevalence in developed and developing countries, it seems probable that, as patterns of morbidity and mortality converge with those of the richer countries, dementia prevalence levels will do likewise, leading to an increased burden of dementia in poorer countries.
Studies in developed countries have consistently reported AD to be more prevalent than VaD. Early surveys from South-East Asia provided an exception, though more recent work suggests this situation has now reversed. This may be due to increasing longevity and better physical health: AD, whose onset is in general later than that of VaD, increases as the number of very old people increases, while better physical health reduces the number of stroke sufferers and thus the number with VaD. This change also affects the sex distribution among dementia sufferers, increasing the number of females and reducing the number of males.
Disability, burden and cost
Dementia is one of the main causes of disability in later life. In a wide consensus consultation for the Global Burden of Disease (GBD) report, disability from dementia was accorded a higher weight than that for almost any other condition, with the exception of spinal cord injury and terminal cancer. Of course, older people are particularly likely to have multiple health conditions — chronic physical diseases affecting different organ systems, coexisting with mental and cognitive disorders. Dementia, however, has a disproportionate impact on capacity for independent living, yet its global public health significance continues to be underappreciated and misunderstood. According to the GBD estimates in The world health report 2003, dementia contributed 11.2% of all years lived with disability among people aged 60 years and over: more than stroke (9.5%), musculoskeletal disorders (8.9%), cardiovascular disease (5.0%) and all forms of cancer (2.4%). However, the research papers (since 2002) devoted to these chronic disorders reveal a starkly different ordering of priorities: cancer 23.5%, cardiovascular disease 17.6%, musculoskeletal disorders 6.9%, stroke 3.1% and dementia 1.4%.
The economic costs of dementia are enormous. These can include the costs of "formal care" (health care, social and community care, respite care and long-term residential or nursing-home care) and "informal care" (unpaid care by family members, including their lost opportunity to earn income).
In the United Kingdom, direct formal care costs alone have been estimated at US$ 8 billion, or US$ 13 000 per patient. In the United States, costs have been estimated at US$ 100 billion per year, with patients with severe dementia costing US$ 36 794 each (1998 prices) (23,24). A more recent estimate is of US$ 18 billion annually in the United States for informal costs alone. In developed countries, costs tend to rise as dementia progresses. When people with dementia are cared for at home, informal care costs may exceed direct formal care costs. As the disease progresses, and the need for medical staff involvement increases, formal care costs will increase. Institutionalization is generally the biggest single contributor to costs of care.
Very little work has been done on evaluating the economic costs of dementia in developing countries. Shah et al. (25) list five reasons for this: the absence of trained health economists, the low priority given to mental health, the poorly developed state of mental health services, the lack of justification for such services, and the absence of data sets. Given the inevitability that the needs of frail older persons will come to dominate health and social care budgets in these regions, more data are urgently needed.
Detailed studies of informal costs outside western Europe and North America are rare, but a careful study of a sample of 42 AD patients in Denizli, Turkey, provides interesting data (26). Formal care for the elderly was rare: only 1% of old people in Turkey live in residential care. Families therefore provide most of the care. The average annual cost of care (excluding hospitalization) was US$ 4930 for severe cases and US$ 1766 for mild ones. Most costs increased with the severity of the disease, though outpatient costs declined. Carers spent three hours a day looking after the most severely affected patients.
The 10/66 Dementia Research Group also examined the economic impact of dementia in its pilot study of 706 persons with dementia and their caregivers living in China, India, Latin America and Nigeria (27). The key findings from this study are summarized in Box 3.1.2.
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Although nobody gets a parenting manual or bible in the delivery room, it is our duty as parents to try to make our kids as well rounded, happy and confident as possible. It is a lot easier to bring up great kids than it is to try and fix problems caused by bad parenting, when our kids have become adults. Our children are all individuals - they are not our property but people in their own right.