What to Expect at the Doctor's Office

It's one thing for a physician to understand the criteria for diagnosing Alzheimer's disease, and quite another to apply them. Yet, doctors diagnose Alzheimer's disease reasonably well based on clinical assessment.



Recently, researchers performed brain autopsies on 220 people who had been diagnosed as having Alzheimer's disease while living. Their diagnoses were based on clinical assessments. On autopsy, 88% had the characteristic brain abnormalities of the disease (neurofibrillary tangles and senile plaques).



On the other hand, 12% of those in the study diagnosed with Alzheimer's did not have it, a finding that underscores the need for more definitive tests.



Currently, a clinical assessment for Alzheimer's typically begins with a consultation with a doctor, often a family physician or perhaps a neurologist. The doctor asks the affected individual and family members or close friends to describe what's been happening, and how the person functions compared with how he or she functioned in the past.



Next comes a complete medical history to see if a condition other than Alzheimer's -- such as Parkinson's disease, stroke, or major depression -- is causing the observed problems.



Part of this process involves several standard laboratory tests:


  • A complete blood count (CBC) to check for vitamin deficiencies and lead poisoning




  • A blood chemistry panel to check for kidney failure and thyroid problems




  • Tests for syphilis and HIV infection




  • Possibly a lumbar puncture to obtain cerebrospinal fluid, which can diagnose meningitis and encephalitis




  • An electroencephalogram to check for Creutzfeldt-Jakob disease




  • A computed tomography (CT) scan or magnetic resonance imaging (MRI) to look for brain tumors, stroke, and other dementing brain conditions


After the doctor has ruled out other possible diagnoses, he or she conducts a structured interview with person's loved ones to assess the degree of the person's cognitive deterioration. Interviews differ. The following questions come from a recent study that correlated well with other diagnostic evaluations for Alzheimer's disease.

  • What was the first problem you noticed with the affected individual?




  • When did you first notice this?




  • Once it started, was the problem always present, or did it happen every now and then?




  • Have you ever noticed memory problems? If so, when did you first notice this? And once it started, was the problem always present, or did it happen every now and then?




  • Have you ever noticed performance problems? If so...




  • Have you ever noticed language problems? If so...




  • Have you ever noticed trouble knowing the date? If so...




  • Have you ever noticed personality changes? If so...




  • Have you ever noticed depression? If so...




  • Have you ever noticed behavior problems? If so...




  • Have you ever noticed hallucinations, delusion, or paranoia? If so...


Next comes an interview with the affected individual to assess cognitive competence. The doctor might test recent and long-term memory by asking: What day is it today? Who are the President, Vice President, and Governor of your state? When was the Vietnam War? When was World War II? When were you married?



Recall tests are also popular. The doctor lists familiar objects -- a pen, a quarter, a shoe, a scarf -- and then asks the person to repeat them. The doctor asks again five minutes later. Other questions might involve calculation: Start at 100, and subtract seven repeatedly. Or judgment: What would you do if you found a stamped, addressed, sealed letter on the sidewalk by a mailbox? People without Alzheimer's typically say: "Someone must have dropped it. I would mail it." People with Alzheimer's might say: "I don't know." Or "Throw it away." Or "Open it."



Following this informal cognitive-function test, most specialists administer a more standardized test of mental function, such as the Mini-Mental State Examination. This brief, 11-question test, developed in 1965, asks a variety of questions: the year, season, date, day, month; the person's state, county, and town of residence; plus a list-repetition exercise, a serial subtraction exercise, and simple writing, copying, and task-completion exercises. The person gets points for correct answers, and based on thousands of scores over 30 years of using this test, doctors can estimate relative level of mental competence or dementia.



If a complete clinical assessment points to Alzheimer's disease, then it's wise to have a physician -- typically a neurologist who specializes in dementing illnesses -- repeat the entire panel of diagnostic tests.