Dementia can be diagnosed with tests
DEAR DOCTOR: How is one screened for/ diagnosed with Alzheimer’s or other forms of dementia? What type of doctors does one see? What sorts of tests do they run? It runs in my family, and lately I’ve been forgetting conversations soon after they happen. But I don’t know where to look for answers.
DEAR READER: Diagnosis typically starts with your primary-care doctor. While blood tests can pick up some non-Alzheimer’s causes for memory loss, such as B12 deficiency, the standard screening exam is the Mini-Mental Status Examination (MMSE), a memory and writing test. Another test, the Montreal Cognitive Assessment (MoCA), has greater sensitivity in identifying losses in the abilities to use language and perform tasks — both common markers for encroaching dementia — so your doctor may use this as well.
These tests can effectively identify people who already have dementia, but they are less effective at identifying people in the early stages of memory loss or those who have memory loss but also have a higher level of brain function. In these cases, much longer and more formal neuropsychological tests may be necessary. This testing is often done by a psychologist associated
with a neurologist.
A neurologist also may order imaging tests of the brain. These tests can include an MRI, positron emission tomography (a PET scan) and possibly functional brain imaging that assesses areas of the brain with low activity. Although some findings might suggest Alzheimer’s, these tests are used primarily to rule out other causes; they can’t yield a definitive Alzheimer’s diagnosis.
The potential to use cerebrospinal fluid biomarkers to help diagnose Alzheimer’s disease is still in the investigational phase and unlikely to be used by a neurologist currently.
So start by talking to your primary-care doctor about the change in your memory, how long it’s been happening and whether it’s rapidly getting worse. Your doctor will likely conduct a standardized test for memory, along with blood work to rule out other causes of memory loss. If that suggests a problem, but no other physical cause, you should see a neurologist for more formal testing.
Robert Ashley, M.D., is an internist and assistant professor of medicine at the University of California, Los Angeles.