Diagnosing Alzheimer’s

It’s scary to consider that you, or a loved one, may have Alzheimer’s disease, the most common type of dementia. Alzheimer’s disease involves the parts of the brain that controls thought, memory, and language. As you may have observed in others, Alzheimer’s can gradually make it hard to carry out even the simplest of daily activities. What is involved in diagnosing Alzheimer’s? Should you go to a doctor for an evaluation? Or should you use an at-home test for Alzheimer’s?

Please note that this post is written for people who are worried about their own cognitive decline. However, the information is also pertinent for those concerned about a loved one’s cognitive decline.

Diagnosing Alzheimer’s: What is Alzheimer’s disease?

Importantly, Alzheimer’s disease is not a normal part of aging. Instead, it occurs when the brain undergoes complex changes that lead to the loss of brain cells and their connections. Interestingly, these changes begin years before any symptoms appear.

Sadly, Alzheimer’s disease slowly destroys memory and thinking skills. Alzheimer’s starts with mild symptoms, but eventually, those with Alzheimer’s lose the ability to carry out even the simplest tasks. Moreover, some people with Alzheimer’s experience personality changes along with difficulties controlling their emotions and other behaviors.

How common is Alzheimer’s disease?

Experts estimate that over 6 million Americans, many of them age 65 and older, have Alzheimer’s disease.

What causes Alzheimer’s disease?

Alzheimer’s dementia is usually associated with abnormal buildups of proteins in the brain – known as amyloid plaques and tau tangles – along with a loss of connection among nerve cells. Interestingly, doctors can see these changes in patient’s brains using a PET scan.

Unfortunately, experts do not fully understand what causes the buildups of proteins and a loss of connection among nerve cells. However, experts believe the causes of Alzheimer’s disease probably include a combination of:

• Age-related changes in the brain – including shrinking, inflammation, blood vessel damage, and a breakdown of energy within brain cells, which might harm neurons and affect other brain cells.
• Genetic changes or differences – which may be passed down by a family member. Both types of Alzheimer’s – the very rare early-onset type occurring between age 30 and mid-60s, and the most common late-onset type occurring after a person’s mid-60s – may be related to a person’s genes. Interestingly, many people with Down syndrome will develop Alzheimer’s as they age and may start to show symptoms in their 40s.
• Health, environmental, and lifestyle factors may play a role, possibly including exposure to pollutants, heart disease, stroke, high blood pressure, diabetes, and obesity.

Diagnosing Alzheimer’s: Watch for signs and symptoms.

Unsurprisingly, memory problems often appear as one of the first signs of dementia or Alzheimer’s. Symptoms can include problems with:

• Word-finding – having more trouble coming up with words than other people the same age.
• Vision and spatial issues – like a lack of awareness of the space around them.
• Impaired reasoning or judgment, which can impact decisions.

Additionally, people with Alzheimer’s may experience changes in behavior, including the following:

• Taking longer to complete normal daily tasks.
• Repeating questions.
• Difficulty handling money and paying bills.
• Wandering and getting lost.
• Losing things or putting items in odd places.
• Changes in mood and personality.
• Increased anxiety and/or aggression.

Cognitive issues can have other causes.

It’s important to understand that a variety of other issues can cause cognitive symptoms. For instance, mini-strokes, sleep apnea, thyroid problems, vitamin B12 deficiency, and medication interactions can each lead to cognitive issues.

Diagnosing Alzheimer’s: What’s the difference between dementia and Alzheimer’s?

Importantly, dementia is an “umbrella term used to describe a range of neurological conditions affecting the brain that get worse over time”. Dementia symptoms include the decline in cognitive abilities and the changes in behavior experienced by people with Alzheimer’s disease.

Understandably, many people use the terms “Alzheimer’s disease” and “dementia” interchangeably.  However, Alzheimer’s disease is just one type of dementia, with other diseases and conditions also causing dementia (see below). But Alzheimer’s disease is the most common cause of dementia in older adults,

What are the other types of dementia?

As mentioned above, Alzheimer’s disease is not the only type of dementia. Other types of dementia include:

• Frontotemporal dementia (FTD) is rare and tends to occur in people younger than 60. FTD is caused by a group of disorders that gradually damage the brain’s frontal and temporal lobes, causing changes in thinking and behaviors. Symptoms can include unusual behaviors, emotional problems, trouble communicating, challenges with work, and difficulty with walking. These changes include abnormal amounts or forms of the proteins tau and TDP-43, and the loss of nerve cells.
• Lewy body dementia (LBD) is a brain disorders that can lead to problems with thinking, movement, behavior, and mood. Patients with LBD commonly experience visual hallucinations (seeing things that are not there) which tend to occur in the early stages. The brains of people with LBD contain abnormal deposits of a protein called alpha-synuclein, also called Lewy bodies.
• Vascular dementia occurs when blood flow to the brain is disrupted, leading to problems with memory, thinking, and behavior.  in people who have vascular changes in the brain, such as a stroke or injury to small vessels carrying blood to the brain. In MRI scans, the brains of people with vascular dementia often show evidence of prior strokes, thickening blood vessel walls, and thinning white matter — the brain’s connecting “wires” that relay messages between regions. Vascular dementia is the second most common dementia diagnosis.

Interestingly, patients may receive a diagnosis of “mixed dementia” related to a mixture of changes in the brain. For instance, a person might have evidence of changes normally associated with both Alzheimer’s and vascular dementia.

Diagnosing Alzheimer’s.

Importantly, there’s no single test that can determine if you have Alzheimer’s disease. Talk to your doctor if you worry about a decline in your cognitive abilities. However, keep in mind it is hard to judge your own cognition, which can make it hard to determine if you need to be tested for Alzheimer’s disease.

To diagnose Alzheimer’s, your doctor will likely use several methods and tools, including the following:

• Ask questions about your overall health, use of prescription and over-the-counter medicines, diet, past medical problems, ability to carry out daily activities, and changes in behavior and personality. The doctor will also ask your family members these questions since cognitive issues can make it hard to accurately answer these questions.
• Conduct tests of memory, problem solving, attention, counting, and language.
• Perform a neurologic exam to check reflexes, coordination, muscle tone and strength, eye movement, speech, and your senses.
• Order blood, urine, and other standard medical tests to identify other possible causes of your cognitive issues.
• Administer a psychiatric evaluation to determine if depression or another mental health condition is causing or contributing to your symptoms.
• Order a spinal tap to collect cerebrospinal fluid (CSF) to measure the levels of proteins associated with Alzheimer’s and related dementias.
• Perform brain scans, such as computed tomography (CT), magnetic resonance imaging (MRI), or positron emission tomography (PET), to support an Alzheimer’s diagnosis. These tests can rule out other possible causes for symptoms.

Ruling out other conditions is a critical part of the diagnostic process for Alzheimer’s since other conditions can present similar cognitive symptoms. In fact, 20% – 30% of patients seen by specialists take medications or have other medical conditions that can mimic Alzheimer’s disease. For example, vascular dementia, depression, thyroid disease, sleep apnea, and vitamin B12 deficiency can each affect cognitive function.

A promising blood test.

A 2024 study found that a new blood test has a 90% accuracy rate for determining if memory loss is due to Alzheimer’s. The test, referred to as “p-tau217 immunoassay”, showed similar diagnostic accuracies to CSF biomarker testing in identifying abnormal beta-amyloid deposits and a build up of tau proteins. Importantly, the presence of beta-amyloid and tau tangles in the brain are hallmark signs of Alzheimer’s.

In comparison, neurologists and other memory specialists only correctly diagnosed Alzheimer’s 73% of the time. And primary care doctors had only a 61% accuracy rate.

An accurate blood test can reduce the need to see a specialist or undergo additional testing. Additionally, it can help patients receive an earlier diagnosis and thereby start treatment earlier.

But more research is needed to verify the positive results, guidelines must be established, and doctors must receive training, before the test will see widespread use.

Diagnosing Alzheimer’s: Should you use an at-home test?

The common methods for diagnosing Alzheimer’s require specialized clinics and trained staff, which can be difficult for some people to access. Additionally, the current evaluation regimen is expensive, time consuming, and invasive.

Should you use an at-home test for diagnosing Alzheimer’s?

AD-Detect test.

You may have heard of Quest Diagnostics’ AD-Detect Test for Alzheimer’s Disease. This test let consumers check their blood to measures amyloid ratios in the blood to determine if there are amyloid deposits in the brain – a hallmark of Alzheimer’s disease.

However, at the end of 2023, the company announced they are only selling the tests to medical professionals. Importantly, AD-Detect has not been cleared or approved by the FDA. And there have been no published peer-reviewed research papers validating its accuracy.

ApoE 4 tests.

Although there are multiple factors that can influence the chance you will develop Alzheimer’s, one of the largest factors is genetics. Specifically, if you have relatives, especially parents, with Alzheimer’s, you have a higher risk of developing the disease.

​The cause behind this genetic link is a gene called ApoE which influences the amount of harmful plaque in the brain.

Your risk of Alzheimer’s depends on which version of the gene you have.

There are three versions of the ApoE gene:

The Kashi Clinical Laboratories website recommends the test for people with following symptoms or conditions:

• Family history of dementia or Alzheimer’s.
• Symptoms of memory loss.
• Pattern of decreasing intellectual ability.
• Reduction in language and speech skills not related to another condition.

Considerations before buying an ApoE 4 test.

Before you test, consider the emotional consequences of learning your result and how it could impact you and your loved ones. Don’t take an at-home test before thinking it through.

Additionally, as suggested by Dr. Cullum, a neuropsychologist and professor, ask yourself these questions:

• Why do I want to know this?
• What will I do with the information?
• How will I react?
• What would I change in my future?

Keep in mind that even with positive results, there is no certainty you will ever get Alzheimer’s or when you might develop symptoms.

Talk to a doctor before buying an ApoE 4 test.

Before you order a test, discuss the pros and cons of the test with your doctor. And make sure you discuss the possible consequences of a positive result.

Additionally, the Alzheimer’s Association suggests you speak with a genetic counselor before deciding to take the test and, and if you decide to test, after you receive the results. You can find a genetic counselor on The National Society of Genetic Counselors website.

Importantly, if you decide to use a test, follow up with your doctor (and a geneticist as needed) to discuss your results.

Diagnosing Alzheimer’s: Early detection can help you and your family.

Getting an early, accurate diagnosis can benefit you in many ways. Firstly, most medicines work best for people who are in the early or middle stages of Alzheimer’s.

Secondly, getting an early diagnosis can help you and your family:

• Plan for the future.
• Consider financial and legal matters.
• Address potential safety issues.
• Learn about living arrangements for the future, as the condition worsens.
• Develop support networks.

Furthermore, getting an early diagnosis provides you with more opportunities to participate in clinical trials or other research studies evaluating possible new treatments for Alzheimer’s.

How do doctors treat Alzheimer’s disease?

Unfortunately, there is currently no cure for Alzheimer’s. However, the FDA has approved several medicines that can help manage some symptoms of the disease. For instance, in July 2023, the FDA approved Leqembi, an anti-amyloid therapy that slightly slows cognitive decline in people with mild cognitive impairment and early-stage Alzheimer’s.

In addition to medications, your doctor may suggest coping strategies to help you manage behavioral symptoms.

Fortunately, researchers are exploring other drug therapies and nondrug interventions to delay or prevent the disease, and to treat symptoms.

Learn more about Alzheimer’s treatments on the National Institute on Aging website.

Diagnosing Alzheimer’s: You can reduce your risk of Alzheimer’s!

NOTE: I updated this post on 10-7-24.