It is forecast that approaching 1 million Australians will suffer from dementia by the year 2050. Alzheimer’s disease (AD), also referred to as senile dementia of the Alzheimer type, or simply Alzheimer’s, is the most common form of dementia.
The German psychiatrist and neuropathologist, Alois Alzheimer, first described this progressive degenerative disease of the brain in which neurones are lost and there is accumulation of amyloid plaques and neurofibrillary tangles in the cerebral cortex, in the early 1900s. The cause of Alzheimer’s disease is still unknown but is thought to involve an interplay between genetic susceptibility and lifestyle factors. Most often, the condition is diagnosed in people over the age of 65 years, although a less-prevalent early-onset form of Alzheimer’s can occur when the disease is familial. The risk of Alzheimer’s increases with age and it is predicted that by 2050 it will affect as many as 1 in every 85 people globally.
Although the course of Alzheimer’s is unique for each individual, there are many symptoms that are common to most cases. The earliest observable symptoms are often mistakenly thought to be ‘age-related’ concerns, or manifestations of stress. In the early stages, the most common symptom is inability to acquire new memories and difficulty in recalling recent events. When Alzheimer’s is suspected, the diagnosis can usually be confirmed using behavioural assessments and cognitive tests, followed by brain scans.
As the disease advances, other symptoms develop, including confusion, irritability and aggression, mood swings, language breakdown, loss of long-term memory, and general withdrawal of the sufferer as their senses decline. Individual prognosis is difficult to assess, as the duration and trajectory of the disease varies considerably. Alzheimer’s can develop for an indeterminate period of time before it becomes apparent, and confirmation of the diagnosis may therefore be delayed for several years. The average life expectancy following diagnosis is approximately seven years, but in a minority of individuals may be up to 15 years or longer.
Currently used treatments offer some limited symptomatic benefit, but treatments to delay or halt the progression of the disease are still not available and remain a major challenge and research priority. Attention to modifiable cerebrovascular risk factors, such as hypertension and high cholesterol is important, as well as hearing loss. A number of life-style interventions, including physical exercise and cognitive activity may aid in the prevention of Alzheimer’s disease or to delay its progress, but are still unproven. Mental stimulation, regular exercise, a balanced diet and phototherapy are recommended, both as possibly aiding prevention and as a sensible way of managing the disease.
In addition to its effects on the sufferer, Alzheimer’s also has a major impact on the carers. The patient’s spouse or a close relative commonly takes on the role of carer, a role that is known to impose an enormous psychological, social, physical, and economic burden on the caregiver. As a consequence, in developed countries, Alzheimer’s is one of the most costly diseases affecting society.