How is Alzheimers diagnosed?
Ans. Since there is no specific laboratory test for Alzheimer’s, it must be diagnosed by exclusion. A physician must rule out all the other potential explanations for symptoms before arriving at a diagnosis of Alzheimer’s. New research into diagnostic markers and the more sensitive scans should soon yield a more definitive test.
At specialized centers, doctors can diagnose “possible” or “probable” Alzheimer’s disease correctly up to 90 percent of the time. Doctors use several tools to diagnose “probable” Alzheimer’s disease. These tools include a complete medical history and tests that measure memory, problem solving, attention, counting, and language abilities. Medical tests such as analysis of blood, urine, or spinal fluid are used to determine if the dementia has another cause.
A “probable” diagnosis can be made with 90 percent accuracy by using some diagnostic tools to rule out other forms of dementia. A complete medical history and physical exam are performed. Since memory is affected early in the disease progression, including information from family members is usually helpful. Blood and urine samples are tested to determine if another disease may be causing symptoms, and neuropsychological testing to determine memory, attention span, and other cognition skills. A brain scan may be performed to determine if any abnormalities are present. The only sure way to diagnose Alzheimer’s is to examine the brain tissue after death during an autopsy.
