I meant to post this early, but the Neurophilosopher has an excellent history of Alois Alzheimer, for whom the disease is named:
On November 25th, 1901, a 51-year-old woman named Auguste Deter (below right) was admitted to the hospital, and was examined by Alzheimer. Deter at first presented with impaired memory, aphasia, disorientation and psychosocial incompetence (which was, at that time, the legal definition of 'dementia'); her condition gradually worsened, and she started losing other cognitive functions and experiencing hallucinations. Because of her age, Deter was diagnosed with presenile dementia; today, the diagnosis would be early-onset Alzheimer's Disease, which is defined as development of the condition before the age of 65.
augusted.jpgDeter died in April 1906, aged 55. By that time, Alzheimer had left Frankfurt, and was working under Emil Kraepelin at the Royal Psychiatric Clinic in Munich. Hearing of Deter's death, he requested from Sioli, the director of the Frankfurt institution where Deter had been, that her medical records be sent to him.
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Ironically, it appears that Deter's death was caused not by the pathologies now associated with Alzheimer's Disease but rather by arteriosclerosis (hardening of the arteries) in the brain.
Read the whole thing.