
Alzheimer's disease (AD) is a progressive neurologic disease of the brain that leads to the irreversible loss of neurons and dementia. This incurable, degenerative, and terminal disease was first described by German psychiatrist Alois Alzheimer in 1906. Generally it is diagnosed in people over 65 years of age, although the less-prevalent early-onset Alzheimer's can occur much earlier.
Although each sufferer experiences Alzheimer's in a unique way, there are many common symptoms. The earliest observable symptoms are often mistakenly thought to be 'age-related' concerns, or manifestations of stress. In the early stages, the most commonly recognised symptom is memory loss, such as difficulty in remembering recently learned facts.
As the disease advances, symptoms include confusion, irritability and aggression, mood swings, language breakdown, long-term memory loss, and the general withdrawal of the sufferer as their senses decline. Gradually, bodily functions are lost, ultimately leading to death. The mean life expectancy following diagnosis is approximately seven years.