How is dementia diagnosed?

Dr. David B. Reuben, MD
Geriatric Medicine Specialist

Dementia is diagnosed after an examination by a clinician, which could be a primary care doctor, a geriatric specialist, a psychiatrist or a neurologist. The examination tests short-term and long-term memory, language, executive functioning, visual-spatial functioning and motor functioning. Most of the time a clinician can establish a diagnosis fairly quickly. Occasionally, however, the diagnosis will be unclear. When that’s the case, doctors will frequently refer for what doctors call neuropsychological testing. Doctors might also do imaging of the brain.

Dementia is diagnosed by the mini-mental state exam (MMSE). Sometimes, a magnetic resonance imaging (MRI) of the brain will show where there's atrophy of white matter. The MMSE exam can also show if it is alcoholic dementia. Historically, we know that excessive drinking can cause vitamin deficiencies and those deficiencies will appear in the vitamin B-12 and folic acid tests.

The main way dementia is diagnosed is by evaluating the patient. Normally, family and friends see a slow decline in the patient’s reasoning, judgment, memory and communication. It’s more of a process, and there’s not just one simple dementia test. Once they are admitted to the hospital, they may have a neuro-cognitive psychologist test, too.

In diagnosing dementia, doctors begin looking for clues from the time the patient enters the office. They check the patients appearance, behavior, mood, motor skills, speech and thought processes.

Understanding the patient's history also provides valuable context to the doctor's observations.

Doctors also try to discern which parts of the patient's brain are affected, and they find out more about this by administering some brief cognitive tests.

Continue Learning about Dementia Diagnosis

Dementia Diagnosis

Dementia Diagnosis

Dementia is diagnosed during a doctor's exam. A person's short-term and long-term memory is tested, along with language, visual-spatial functioning and motor skills. If a diagnosis is unclear, a referral for neuropsychological tes...

ting and a brain scan may be needed. Learn more about dementia diagnosis with expert advice from Sharecare.

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.