I Took the New Alzheimer’s Blood Test

When my dad was diagnosed with dementia at a relatively young age, it changed the way I think about my own future. It’s one thing to read about Alzheimer’s disease in the news. It’s another thing entirely to watch someone you love slowly become someone you barely recognize.

Like a lot of people with a family history of dementia (my dad and his dad), I’ve wondered what that might mean for me and my siblings. Every time I forgot why I walked into a room or couldn’t remember someone’s name right away, I’d catch myself wondering if it was just normal life or something more. Deep down, I knew I couldn’t spend the rest of my life worrying about every little memory lapse, but I also didn’t know if there was anything proactive I could do.

That changed during my annual physical.

As we were talking about my family history, my doctor asked if I had ever heard of the Alzheimer’s blood test. I stared at her for a second because I honestly thought I had misunderstood what she said. A blood test? For Alzheimer’s? (AD-DIRECT A BETA 42/40 AND P-TAU 217 EVALUATION.) I knew doctors sometimes used brain scans or spinal taps when evaluating patients with memory problems, but I had no idea there was now a blood test that could help identify biological changes associated with Alzheimer’s disease.

Apparently, I’ve been behind on my medical news.

My doctor explained that although these tests are currently intended primarily for people who are experiencing cognitive symptoms, the science has advanced incredibly quickly. She also told me she believes that by the time I’m 55, testing like this could become much more common as part of evaluating brain health. That was her opinion based on where the field is headed, not an official recommendation, but it certainly made me realize how rapidly Alzheimer’s research is evolving.

Since I had just turned 46 and have a significant family history, she offered to let me take the test. I didn’t hesitate. I replied yes immediately. I always wondered if I was the type of person who “would want to know” and it turns out I am.

What Is the Alzheimer’s Blood Test?

If you’re hearing about this for the first time, you’re not alone because I had never heard of it either.

The newest FDA-cleared Alzheimer’s blood tests look for proteins in your blood that are associated with the changes seen in Alzheimer’s disease, including a protein called phosphorylated tau (pTau217) and changes related to amyloid. These biomarkers can help doctors determine whether someone may have the brain changes associated with Alzheimer’s disease, but the blood test is not a standalone diagnosis.

Instead, doctors use the results along with a patient’s symptoms, medical history, neurological exam, and sometimes additional testing such as PET imaging or cerebrospinal fluid testing. In other words, this isn’t like getting a cholesterol number where you’re either above or below a certain level. It’s one piece of a much bigger picture.

That’s an important distinction because I don’t want anyone reading this to think the test can predict their future with certainty. It can’t.

Inside my own MyChart, it explained that this test does the following:

This panel combines beta amyloid 42/40 and p-tau217 plasma scores to provide an assessment of the likelihood of amyloid plaque deposition in the brain. A score of less than 0.3254 is consistent with a low likelihood of a positive amyloid PET scan in someone with cognitive impairment. This determination cannot diagnose Alzheimer’s disease by itself and should be used in combination with the patient’s clinical history and presentation.

Taking the Test Was the Easy Part

The actual blood draw couldn’t have been more routine. If you’ve ever had blood work during an annual physical, you already know what to expect. There weren’t any extra preparations, no special instructions, and no lengthy appointment.

What surprised me wasn’t the test itself. It was the waiting.

I’m used to getting cholesterol results or other routine lab work fairly quickly through my patient portal. This time, days went by with nothing. Then a week passed. Every time my phone buzzed with a notification, I wondered if that would be the one.

I kept telling myself that whatever the results were, I couldn’t change them by worrying. As you can probably guess, that advice was much easier to give myself than it was to actually follow.

I Got My Results in the Middle of Vietnam

Life didn’t stop while I was waiting. In fact, by the time my results were ready, I was halfway around the world on a trip through Vietnam.

We were riding a bus through the stunning Hai Van Pass, one of the most beautiful stretches of road in the country. If you’ve ever been there, you know the views are absolutely incredible. Mountains, coastline, lush greenery. It’s the kind of place where you should be looking out the window instead of staring at your phone but obviously, I was checking mine.

Before I left for the trip, I had made a promise to myself. If the results came in while I was traveling, I wouldn’t look at them until I got home. I didn’t want to risk getting difficult news while I was thousands of miles away from home.

Then my phone buzzed. The notification from my patient portal popped onto the screen, and suddenly my brilliant plan went right out the window. My self-control lasted all of about five seconds.

I logged in, opened the results, and immediately started scanning for the part that mattered most. The words I saw were:

Low likelihood.

I actually read them twice because I wanted to make sure I wasn’t misunderstanding what I was seeing. Then I read the results out loud to everyone on the bus. As soon as they realized what the report said, the entire group started cheering. It was one of those moments I’ll probably remember for the rest of my life.

After carrying around so much worry because of my dad’s diagnosis, hearing that my results indicated a low likelihood of Alzheimer’s-related pathology felt like someone had lifted a tremendous weight off my shoulders.

What “Low Likelihood” Actually Means

As relieved as I was, I also want to be careful not to overstate what my results mean.

A “low likelihood” result does not guarantee that I’ll never develop Alzheimer’s disease. It also doesn’t mean I never have to think about my brain health again. Like every medical test, this one has limitations and needs to be interpreted by a healthcare provider in the context of your overall health.

For me, though, it was reassuring news.

Instead of wondering whether my blood work showed evidence that would raise immediate concerns, I was able to take a deep breath and enjoy the rest of my trip knowing that, at least today, there wasn’t an indication that I needed additional Alzheimer’s testing.

Should You Ask Your Doctor About It?

If Alzheimer’s or another form of dementia runs in your family, I think it’s absolutely worth asking your doctor whether this type of testing makes sense for you.

That doesn’t mean everyone should rush out and request it tomorrow. Current blood tests are primarily intended to help evaluate people who have cognitive symptoms, and whether it’s appropriate depends on your age, medical history, family history, and your doctor’s clinical judgment.

The important thing is knowing that the conversation is now possible. Before my appointment, I didn’t even know this test existed. If my doctor hadn’t brought it up, I never would have known to ask.

Supporting Your Brain Health

While no lifestyle change can guarantee you’ll avoid Alzheimer’s disease, researchers have identified several habits that are associated with better brain health. Regular physical activity, keeping blood pressure under control, eating a Mediterranean-style diet, getting enough sleep, staying socially engaged, and continuing to challenge your brain through learning all appear to play a role in maintaining cognitive health.

Those are things that benefit your heart and the rest of your body too, so they’re worthwhile regardless of your test results.

Some things I have specifically done in the last few months to reduce my risk are:

• More cardio aka rollerblading
• Supplements: NMN, NAD, Vit B, and Vit D
• More squats (leg strength is a really big deal)

My Biggest Takeaway

The biggest lesson I learned from this experience wasn’t really about the blood test itself.

It was about asking questions.

For months, maybe even years, I worried about my family history without realizing there was a new tool that might provide additional information. That conversation with my doctor gave me knowledge I didn’t have before, and while waiting for the results was nerve-racking, I’m grateful I chose to do it.

Watching my dad’s journey with dementia has been heartbreaking, and I know there are no guarantees for any of us. But standing on that bus in Vietnam, surrounded by people cheering after I read the words “low likelihood,” reminded me that sometimes good news is worth celebrating loudly.

If Alzheimer’s has touched your family too, I hope this encourages you to have a conversation with your doctor. The blood test may or may not be appropriate for your situation, but knowing your options is always better than wondering what they are.

Sources

• U.S. Food & Drug Administration. FDA Clears First Blood Test Used in Diagnosing Alzheimer’s Disease. https://www.fda.gov/news-events/press-announcements/fda-clears-first-blood-test-used-diagnosing-alzheimers-disease
• Alzheimer’s Association. Blood Tests for Alzheimer’s Disease. https://www.alz.org/alzheimers-dementia/research_progress/blood-tests
• National Institute on Aging. Alzheimer’s Disease Fact Sheet. https://www.nia.nih.gov/health/alzheimers-and-dementia/alzheimers-disease-fact-sheet