Alzheimer's Disease 1906 – The Autopsy of Auguste Deter

In 1994, former US President Ronald Reagan wrote, "I was recently told that I would be one of the millions of Americans to develop Alzheimer's disease... I now begin the journey that will lead me to the end of my life." A year later, diners in a restaurant applauded him, but he did not know why they were applauding or that he had once been president.

Alzheimer's disease (AD) is a form of dementia, a general term for memory loss and the abnormal loss of other cognitive abilities. AD destroys brain cells and impairs the ability to form new memories. As the disease progresses, long-term memories and language abilities are lost. The average life expectancy after the initial diagnosis is approximately seven years.

Brain plaques and tangles are two abnormal features of AD. Plaques accumulate between nerve cells and contain protein fragments called beta-amyloid (BA). Tangles consist of twisted fibres of a microtubule-associated protein called tau and are found inside dying cells. Research continues into the role of plaques and tangles in AD and how they may disrupt signals between nerve cells and kill cells.

In 1906, German psychiatrist and neuropathologist Alois Alzheimer presented the case of Auguste Deter, who initially experienced memory problems at the age of 51 and soon developed delusions and more severe mental problems. An autopsy revealed dramatic shrinkage of Deter's cerebral cortex (the layer of the brain involved in memory, thought and language) and the presence of BA plaques and neurofibrillary tangles.

Today, AD is usually diagnosed on the basis of a patient's behaviour. Advanced medical imaging methods such as CAT, MRI and PET may be used to look for other possible causes of dementia. 

Cerebrospinal fluid allows analysis for the presence of BA or tau proteins to help diagnose the disease before its associated symptoms have appeared. 

Alzheimer's disease most often develops after the age of 65. A form of a gene called APOE has been found to be strongly associated with developing AD. 

Description of the article image: A cross-section of a healthy brain (left) and a brain from a person with Alzheimer's disease (right), showing dramatic shrinkage of the cerebral cortex.

Historical figures mentioned in the article: Aloysius “Alois” Alzheimer (1864–1915) 

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