Blood Tests for Alzheimer’s Disease

Overview of Blood Tests for Alzheimer’s Disease

Blood tests can be an integral component for accurately diagnosing Alzheimer’s disease, and these tests have seen significant advancements in recent years. Using a sample from a simple blood draw, the tests measure the amount of two proteins in the blood that are commonly associated with Alzheimer’s – beta-amyloid and tau. The results of the test should not be used on their own to diagnose Alzheimer’s, but they should be interpreted by specialists and used alongside clinical evaluations and other tests to assess patients who are experiencing cognitive problems and may have Alzheimer’s disease.

Many of these blood tests for Alzheimer’s require a prescription or a physician’s order, but even if they don’t, they should be administered by a healthcare professional in clinical setting, and, as mentioned above, the results should be interpreted by a specialist. Therefore, taking any of these tests does require consulting and working with healthcare professionals and specialists, even if the test itself can be obtained without their permission.

Blood tests could potentially replace costly positron emission tomography (PET) scans and invasive cerebrospinal fluid tests (spinal taps) as the primary tests for Alzheimer’s disease biomarkers. PET scans and spinal taps can also be used to calculate the ratio of the hallmark proteins, but they are not available in primary care offices, where most cases of cognitive impairment are first encountered. Blood tests, on the other hand, could easily be administered in that setting. This availability would lead to more expedient diagnoses for thousands of patients, allowing them to start treatment sooner and giving them a better chance to slow the disease’s progress.

Federal Drug Administration Approval for Lumipulse Test

The access to blood tests for Alzheimer’s can not be fully realized until they are approved by the Federal Drug Administration (FDA) and then covered by insurance, including Medicare and Medicaid. The first step in that process occurred on May 16, 2025, when the FDA cleared for marketing the Lumipulse G pTau217/ß-Amyloid 1-42 Plasma Ratio test, commonly known as the Lumipulse blood test.

“Today marks another important step in Alzheimer’s disease diagnosis,” Alzheimer’s Association chief science officer and medical affairs lead Maria C. Carrillo, Ph.D., said at the time. “For too long Americans have struggled to get a simple and accurate diagnosis; with today’s action by the FDA we are hopeful it will be easier for more individuals to receive an accurate diagnosis earlier.”

The Lumipulse blood test is made by Fujirebio Diagnostics, a Japanese company. The FDA also approved an earlier version of the Lumipulse test made by Fujirebio, but that test required a spinal tap. The Lumipulse blood test is expected to cost between $500 and $1,000.

During the approval process for the Lumiupulse blood test, the FDA examined data from a clinical study of 499 adults who were cognitively impaired. The results showed that 91.7% of those who tested positive for amyloid plaques on the Lumipulse test also tested positive with PET scans or spinal taps, and 97.3% who tested negative with Lumipulse also tested negative with PET scans or spinal taps.

“These findings indicate that the new blood test can reliably predict the presence or absence of amyloid pathology associated with Alzheimer’s disease at the time of the test in patients who are cognitively impaired,” read the FDA press release announcing the Lumipulse approval. “The test is intended for patients presenting at a specialized care setting with signs and symptoms of cognitive decline. The results must be interpreted in conjunction with other patient clinical information.”

Other Blood Tests for Alzheimer's Disease

There are several other blood tests for Alzheimer’s disease that calculate the ratio of the hallmark proteins. These include the PrecivityAD2 test from C2N Diagnostics, which accurately predicted Alzheimer’s disease in 88% to 92% of 799 participants in a highly-regarded 2024 study that was funded, in part, by the National Institute of Health. The cost for PrecivityAD2 can be as much as $1,450.

The Quest AD-Detect portfolio offers multiple blood panel tests to measure the presence of Alzheimer’s telltale proteins. The AD-Detect ABeta panel, which is part of the portfolio, is 91% accurate when it comes to calculating the likelihood of amyloid pathology that predicts Alzheimer’s disease. The AD-Detect test costs $399, plus administration fees. This test does not require a prescription or doctor’s order.

ALZpath, labcorp and Roche Diagnostics (in conjunction with Eli Lilly) have also developed blood tests for Alzheimer’s disease.

None of these blood tests are covered by private insurance, Medicaid or Medicare. That includes the Lumipulse test. Even though it’s FDA-approved, insurance coverage is still being established for Lumipulse.

How to Acquire and Use Blood Tests for Alzheimer's Disease

As mentioned above, a prescription or a physician’s order is needed to acquire most of these tests. There are some exceptions, like the Quest AD-Detect, but even this test, like all of these blood tests for Alzheimer’s, should be administered and interpreted by healthcare professionals. So, consulting and working with a doctor is a necessary part of the process.

These tests are not intended for home use. While knowing the results can be helpful for Alzheimer’s patients and their families, the test results should only be interpreted by Alzheimer’s disease specialists, as mentioned. It’s important to remember that blood tests for Alzheimer’s can not be used by themselves to diagnose the disease. Their results need to be evaluated by specialists alongside clinical evaluations, cognitive and memory tests and, if necessary, neurological evaluations.

These tests are not intended as a screening tool for healthy adults, so seniors who don’t have any Alzheimer’s disease symptoms should not get tested. The FDA-approved Lumipulse test, for example, is only approved for adults age 55 and older who are experiencing thinking or memory problems.