Alzheimer’s disease overview
Alzheimer’s disease is a progressive brain disorder, in which the brain gradually degenerates. It most frequently occurs in people aged above 65–70 years. People with Alzheimer’s disease develop distressing changes in memory, thought, function and behaviour, which worsen over time. These changes increasingly impact upon the person’s daily life, reducing their independence, until ultimately they are entirely dependent on others.
Alzheimer’s disease also has an enormous impact on the patient’s caregiver.1 Most caregivers are close relatives who provide care in the home – a demanding and exhausting role that represents a huge emotional and physical burden.1
Alzheimer’s disease damages and kills brain cells, leading to significant brain shrinkage and neurotransmitter imbalances. As the brain cells degenerate, characteristic waste accumulates in the brain, known as ‘plaques’ and ‘tangles’.
The symptoms of Alzheimer’s disease emerge gradually, over a period of years, and vary from person to person. The first symptoms to appear are usually forgetfulness and mild confusion. Symptoms of Alzheimer’s disease can be broadly categorized into cognitive, functional and behavioural/psychological changes.
- Cognitive changes – impaired short-term memory (such as impaired knowledge of recent events, repeating oneself, losing items around the house, poor organization), difficulty in making decisions, reduced understanding of the concept of time and space, reduced ability to learn and problems recognizing friends and family.
- Functional changes – reduced ability to perform normal daily activities, as well as more complex tasks: difficulty handling money, difficulty maintaining personal hygiene, incontinence, difficulty getting dressed, imbalance and unsteady movement. Ultimately, Alzheimer’s sufferers will usually become completely bedridden.
- Behavioural/psychological changes – patients may also develop behavioural and psychological disturbances, which increase the burden of care. They may develop and express socially inappropriate behaviour such as delusions, agitation/aggression, depression/dysphoria and appetite/eating changes. Behavioural changes are particularly difficult for family and carers to deal with, and are often the reason for patients being moved to institutional care.
Worldwide, 36 million people have dementia.2 Perhaps as many as 28 million of the world’s 36 million people with dementia have yet to receive a diagnosis and, therefore, do not have access to treatment, information and care.2 Every year, an estimated 4.6 million new cases are identified.3 With the shift towards an increasingly elderly population, it is predicted that the number of people affected by dementia will almost double every 20 years, and by the year 2050, 115 million people will have the condition.2
Alzheimer’s disease is the most common cause of dementia, accounting for 50–70% of cases.4
The worldwide costs of dementia (US$604 billion in 2010) amount to more than 1% of gross domestic product (GDP).2
Seeking diagnosis and care
People who are concerned that they – or their loved ones – are experiencing symptoms of Alzheimer’s disease should see their doctor for help and advice. Alzheimer’s disease is diagnosed using patient and caregiver interviews; sometimes blood tests and brain imaging techniques are also performed. There are numerous assessment scales that can be used to identify the symptoms, and severity, of the disease.
Treatment is available to help alleviate the symptoms of Alzheimer’s disease. However, there is currently no cure.
1. Georges J, Jansen S, Jackson J, et al. Alzheimer’s disease in real life – the dementia carer’s survey. Int J Geriatr Psychiatry 2008; 23 (5): 546–551.
2. Alzheimer Disease International. World Alzheimer Report 2011. The benefits of early diagnosis and intervention. Published by Alzheimer’s Disease International (ADI), September 2011.
3. Ferri CP, Prince M, Brayne C, et al. Global prevalence of dementia: aDelphiconsensus study. Lancet 2005; 366 (9503): 2112–2117.
4. Alzheimer’s Association. Basics of Alzheimer’s disease: what it is and what you can do. 2010. http://www.alz.org/national/documents/brochure_basicsofalz_low.pdf. Accessed 30/09/11.