James M Turnbull
Good judgement comes from experience,
but experience comes from bad judgement.
—John F Kennedy
In 1996, 1545 articles dealing with the subject of Alzheimer's disease appeared in scientific journals. Despite tremendous scientific interest and research, the diagnosis remains a clinical one before death. There are no specific antemortem markers for it.
In 1984 a work group on the diagnosis of Alzheimer's disease was established by the National Institute of Neurological and Communicative Disorders and Strokes (NINCDS) and the Alzheimer's Disease and Related Disorders Association (ADRDA). The clinical criteria for the diagnosis of probable, possible, and definite Alzheimer's disease were outlined. The diagnosis of probable Alzheimer's disease, it was stated, could be made with confidence if the dementia had a typical insidious onset with progression and no other systemic or brain diseases were present, which could account for the progressive memory loss and other cognitive deficits. Using the criteria for probable Alzheimer's disease, two recent large autopsy studies, one by Gearing and the other by Galasko, have reported confirmation rates of 87% and 90%, respectively.
Among the disorders that must be calculated are major depression, Parkinson's disease, multiinfarct dementia, drug intoxication, thyroid disease, vitamin B12 deficiency, subdural hematoma, occult hydrocephalus, Huntington's disease, brain tumors and chronic infections of the nervous system. The criteria for clinical diagnosis of Alzheimer's disease are shown in Box 8-1.
The diagnostic and statistical manual of the American Psychiatric Association was revised in 1994. It lists the diagnostic criteria for dementia of the Alzheimer's type (DAT) as multiple cognitive deficits manifested by impairment in short-term and long-term memory and at least one other area of higher cortical functioning. The latter include impairment in abstract thinking, judgment, or other executive functions, or disturbances such as aphasia (disorder of language), apraxia (inability to carry out motor activities despite intact comprehension and motor