Alzheimer's disease is a form of dementia that today is well understood in the community as a major cause of memory impairment and progressive, usually irreversible, mental decline in old age. While many other conditions can cause dementia, Alzheimer's disease is the most common and attracts the greatest attention. Many well-known people, including former US president Ronald Reagan, actor Charlton Heston and author Iris Murdoch (whose illness was portrayed in the movie Iris) are openly mentioned as sufferers. Most of us know of someone with the disorder; frequently it is a family member.
Memory impairment in old age has long been recognised as common, but until about 30 years ago was usually regarded as a normal part of the ageing process (senescence). In the 1970s, post-mortem studies of the brains of older people who were senile when they died revealed the microscopic appearances of Alzheimer's disease, which up until that point was believed to be a rare condition afflicting people between 40 and 60 years of age. Named after the German neurologist Alois Alzheimer, who first reported it in 1906, Alzheimer's disease was little more than a footnote in most medical textbooks.
Dramatic changes have taken place since that discovery in the 1970s. Alzheimer's disease, along with other dementias, is now recognised as a major public health concern and has become the target of action plans at all levels of government. There are currently around 165 000 persons with dementia among Australia's 19 million population. The personal and social costs of the disease are enormous.
Largely ignored by medical researchers in the past, Alzheimer's disease is now the focus of numerous public and private research efforts worldwide, with attempts underway to identify causal factors, preventive measures, treatments and even cures. Textbooks, journals and conferences are now devoted entirely to Alzheimer's