Medical Test for Dementia and Alzheimer's

Medical Test for Dementia and Alzheimer's

Changes in memory and forgetfulness are often a normal part of the aging process. However, cognitive impairment that affects a person’s ability to carry out day-to-day activities could be an early sign of dementia. If you or someone you know is experiencing persistent memory problems, it’s a good idea to bring this to your doctor’s attention.

Possible causes for memory loss include vitamin deficiencies, certain medications, lifestyle factors, mild cognitive decline, and dementia. Only a doctor can properly assess your symptoms and identify the root cause, but how exactly is dementia detected?

Importance of Early Detection of Dementia

Dementia is a progressive illness, meaning the symptoms get worse over time. There is currently no cure for dementia but with early diagnosis,[1] dementia patients have quicker access to support. Early diagnosis also helps people with dementia understand their symptoms and how to manage them.

Support for dementia patients is multifaceted. It involves a combination of emotional support from friends and family members and practical help for navigating daily tasks. Legal and financial advice may also be necessary, as it allows the patient to plan for their future care. The sooner a person is diagnosed, the sooner they can get their support system in place so they can live well.

Medical Test for Dementia and Alzheimer's

There is no single test for Alzheimer’s or any other type of dementia. When determining if a patient has dementia,[2] doctors will consider the results of various cognitive and psychological assessments, diagnostic tests, and medical history.

The doctor will ask about the patient’s symptoms as well as their diet, lifestyle, use of medications, and consumption of alcohol and other substances. They will also perform a physical examination, including blood pressure, temperature, and heart rate checks. They may also collect blood or urine samples for laboratory testing.

These initial tests will help the doctor identify any health issues that could cause dementia-like symptoms. If they suspect the patient’s symptoms indicate dementia, they may arrange for further medical testing.

Cognitive Tests For Dementia

People with dementia symptoms are often given tests to check their cognitive abilities. These tests, also known as cognitive assessments,[3] are designed to assess a person’s memory, awareness, and thinking skills. There are several different tests used to identify possible cognitive impairment, including the MMSE, MoCA, clock drawing test, 30-question cognitive test, and SAGE.

  • Mini-Mental State Examination (MMSE)

The Mini-Mental State Examination (MMSE) is a 30-point test used to detect mild cognitive impairment[4] (MCI) in people with suspected dementia. The questions in the MMSC test a person’s orientation, concentration, verbal memory, naming, and visuospatial skills. The scores of the MMSE are interpreted as follows:[5]

  • 25 - 30: Normal cognitive function
  • 21 - 24: Mild cognitive impairment
  • 10 - 20: Moderate cognitive impairment
  • Below 10: Severe cognitive impairment
  • Montreal Cognitive Assessment (MoCA)

The Montreal Cognitive Assessment (MoCA)[6] is a simple, 10-minute test used to detect MCI and early signs of dementia. It is similar to the MMSE, but the MoCA test is more sensitive and better for detecting MCI and early dementia. However, it is harder than the MMSE and, therefore, less suitable for people with moderate to severe dementia. The MMSE is more useful for monitoring subtle changes in cognitive function among those with moderate to severe dementia.

  • Clock Drawing Test

The clock drawing test, also known as the CDT, is a simple exercise used to detect warning signs of dementia. A person with suspected dementia is asked to draw a clock[7] showing 10 minutes after 11. If they do so correctly, they have passed; if they draw the clock abnormally, this indicates a need for further testing.

  • SAGE (Self-Administered Gerocognitive Examination) Test

The Self-Administered Gerocognitive Examination (SAGE) is a self-conducted test that can detect early warning signs of dementia. It measures a variety of cognitive functions[8] including memory, thinking skills, and logic. The SAGE is slightly more difficult than the MMSE, which means it’s more sensitive and better for detecting very mild cognitive impairment.

Imaging Tests

Imaging tests are used to check for changes in brain structure. They are primarily used to look for[9] signs of stroke, brain tumors, or other problems that can cause dementia-like symptoms. Imaging tests can also be used to detect structural and functional changes in the brain that indicate Alzheimer’s disease.

  • MRI Scan

A Magnetic Resonance Imaging (MRI) scan is used to produce a detailed image of the brain. It is typically used to look for other problems that could be causing a person’s dementia symptoms, such as a stroke or brain tumor. An MRI can be used to confirm a diagnosis of dementia[10] or provide information about blood vessel damage caused by vascular dementia. It can also show shrinkage to regions of the brain seen in Alzheimer’s disease and frontotemporal dementia.

  • CT Scan

A Computerized Tomography (CT) scan is the most common type of scan used in dementia diagnosis. It can be used to identify other medical conditions that cause dementia-like symptoms, such as brain tumors. A CT scan can also identify changes in brain structure caused by Alzheimer’s disease.

  • PET Scan

A Positron Emission Tomography (PET) scan is used to measure the concentration of specific molecules in the brain. For example, an amyloid-PET scan can detect the build-up of amyloid proteins in the brain, which is a key indicator of Alzheimer’s disease.[11]

Biomarker Tests

Biomarkers are biological molecules found in blood, other bodily fluids, tissues, and organs. They can be indicators of disease, and the presence of some biomarkers can be a sign of dementia.

  • Cerebrospinal Fluid Analysis

Cerebrospinal fluid analysis is often used to support a diagnosis[12] of Alzheimer’s disease. Alzheimer’s disease is characterized by the build-up of abnormal proteins, called amyloid and tau proteins, in the brain. These proteins can also be detected in cerebrospinal fluid.[13]

Doctors use a technique called a lumbar puncture to collect cerebrospinal fluid for analysis. During this procedure, a needle is used to draw a sample of the fluid from the lower back. If the analysis finds an abnormal concentration of amyloid or tau proteins in the fluid, this could confirm that the patient has Alzheimer’s disease.

  • Blood Tests for Biomarkers

Researchers are currently developing a test[14] to detect amyloid and tau proteins in the blood. Once this test is available, it could be used to diagnose Alzheimer’s disease with a simple blood test, which is less invasive than a lumbar puncture.

So far, scientists have identified 11 biomarker proteins that could predict dementia. In the future, blood tests that can detect these biomarkers could be used to accurately predict dementia 15 years ahead of diagnosis.[15]

Genetic Testing

Genetic tests are not routinely used to diagnose dementia. However, research suggests a genetic risk factor for dementia. People with a parent or sibling who has Alzheimer’s disease are at higher risk[16] of developing Alzheimer’s themselves. Therefore, those with a family history of Alzheimer’s disease may undergo genetic testing to find out if they’re also at risk.

  • Apolipoprotein E (APOE) Genotyping

Late-onset Alzheimer’s, which develops after age 65, is the most common type of Alzheimer’s disease. Scientists have identified several genes linked to dementia, but the gene best known to increase late-onset Alzheimer’s risk is the apolipoprotein (APOE) gene. Certain variants of the APOE gene are associated with a higher risk[17] of Alzheimer's, and they can be passed on through families. Genetic testing can be used to determine which APOE variants you have and, therefore, whether you are at greater risk of future dementia.

  • Genetic Counseling

Genetic counseling informs[18] you how genetic conditions, like dementia, could affect you and your family. Genetic counseling should always come before genetic testing, so you can be prepared for all possible outcomes.

Behavioral Assessment

Dementia causes changes in behavior,[19] personality, and mood. Behavioral assessment can identify behaviors or symptoms that could indicate a person has dementia. It can also help clinicians and carers recognize behavioral changes that could indicate a progression in symptoms.

Behavioral Symptoms Checklist

Certain behaviors and symptoms are considered warning signs of dementia and could be a sign that it’s time to see a doctor. These include:[20]

  • Changes in memory that cause difficulties in day-to-day routine
  • Difficulty with familiar tasks, such as preparing a meal or getting dressed
  • Difficulty in communication, struggling to recall words
  • Confusion around time and location, e.g., getting lost in familiar places
  • Impaired judgment, e.g., not keeping up with personal hygiene, carelessness concerning personal safety, etc.
  • Difficulty with abstract thinking, e.g., managing finances, or trouble understanding numbers and symbols
  • Misplacing items in odd places, e.g., leaving keys in the fridge
  • Severe changes in mood, personality, or behavior
  • Loss of initiative, becoming passive and disinterested in life
  • Visuospatial issues, e.g., difficulty moving around their environment or placing objects on tables

Functional Assessment Staging Tool (FAST)

The Reisberg Functional Assessment Staging Tool (FAST) is used to assess cognitive decline[21] in people with dementia. This helps clinicians and caregivers monitor the progression of symptoms and how effective certain treatments are.

The FAST scale details seven stages of dementia[22] and can help define how advanced the patient’s condition is. The seven stages of the FAST scale are as follows:[23]

  • Stage 1: Normal aging
  • Stage 2: Possible mild cognitive impairment
  • Stage 3: Mild cognitive impairment
  • Stage 4: Mild dementia
  • Stage 5: Moderate dementia
  • Stage 6: Moderately severe dementia
  • Stage 7: Severe dementia

Supporting Someone With Dementia

People living with dementia often require emotional and practical support. This depends heavily on the severity of their symptoms and may range from finding fun activities to do together to assisting with day-to-day tasks. There are lots of resources available to support both people with dementia and carers.




























How can I test myself for dementia?

There is no single test for dementia, and only a doctor can make an informed dementia diagnosis. If you’re worried about your memory, discuss your symptoms with a doctor so they can perform the necessary health assessments and tests.

What is a quick test for dementia?

Unfortunately, there is no quick test for dementia. During your initial doctor’s visit, the physician will probably ask about your symptoms and medical history. They may also perform a physical examination and take urine or blood samples to check for other health issues. If they suspect dementia, you may be scheduled for imaging tests, biomarker tests, or genetic tests to confirm the diagnosis.

Can bloodwork detect dementia?

Researchers are currently developing biomarker blood tests that could soon be used to detect or predict dementia. These tests analyze concentrations of specific proteins in the blood, elevated levels of which could indicate Alzheimer’s disease. Currently, the only way to perform these biomarker tests is with a lumbar puncture and cerebrospinal fluid analysis.

What is the best test for dementia?

If you or someone you know has suspected dementia, there are a series of tests needed to confirm a diagnosis. These include cognitive performance tests, imaging tests, and, possibly, biomarker tests.

How does a doctor confirm dementia?

A doctor will diagnose dementia when they notice a loss of cognitive function that can’t be explained by other medical conditions or lifestyle factors. They may use brain imaging tests, like an MRI, CT, or PET scan, or biomarker tests to confirm their diagnosis.


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About The Author

Mary Anne Roberto, the co-founder of Always Home Connected is a dedicated CNA and a Certified Positive Approach To Care Consultant (Teepa Snow), specializing in dementia care.  Her goal is to create awareness about those experiencing cognitive changes and to provide caregivers with resources and tools that are necessary to help alleviate some of the challenges caregivers face on a day-to-day basis.