P-tau217 Testing: Clinical FAQs Answered

Plasma biomarkers are reshaping how primary care providers evaluate early cognitive concerns.

As p-tau217 testing becomes more widely available, many clinicians are asking practical questions — how to use it, when to order it, and what results really mean.

We built this FAQ to provide the clarity you need to bring evidence-backed biomarker testing into everyday care.

Read on to learn more about how we interpret results, when we use the test, how we talk with patients about findings, and how it supports a prevention-driven approach to memory health.

What makes p-tau217 clinically meaningful compared to other biomarkers?

P-tau217 stands out because of its strong specificity for Alzheimer’s pathology. It closely mirrors changes seen in amyloid and tau PET imaging, making it one of the most reliable blood-based markers available today.

For primary care, this translates into earlier clarity — especially when symptoms are subtle or mixed.

Compared with biomarkers like p-tau181, total tau, or NfL, p-tau217 offers a more direct signal tied to Alzheimer’s disease processes.

Key differentiators include:

• Higher specificity for Alzheimer’s pathology
• Stronger concordance with amyloid/tau PET
• Earlier elevation across the disease continuum
• Greater diagnostic stability in mixed or ambiguous cases

When should I consider suggesting p-tau217 testing in primary care?

P-tau217 is most helpful when you’re evaluating early or uncertain cognitive changes and want clearer biological insight without immediately escalating to imaging or specialty care.

It supports decision-making when symptoms are mild, fluctuate, or present with overlapping causes.

In primary care, you may consider ordering p-tau217 when you see:

• Subjective cognitive decline with a family history of dementia
• Mild forgetfulness not yet meeting MCI criteria
• Mixed presentations where risk stratification helps guide next steps
• Patients seeking prevention-focused evaluation
• Persistent patient or family concern despite normal screening results

Using p-tau217 early allows you to act proactively rather than waiting for progression.

What does an elevated p-tau217 result actually indicate?

An elevated p-tau217 result suggests a higher likelihood of Alzheimer’s-related brain changes, even before cognitive impairment becomes measurable. It is not a diagnosis in itself, but it provides meaningful context for your clinical assessment.

We encourage clinicians to interpret elevated results in conjunction with cognitive screening, functional assessments, and patient history.

Together, these diagnostic tools help to create a clearer picture of what may be driving symptoms.

Interpretation considerations include:

• Degree of elevation
• Symptom timeline and severity
• Age and comorbidities
• Family history or genetic risk
• Other biomarker or cognitive testing results

An elevated result is an early signal that further evaluation, closer monitoring, or referral may be appropriate.

How should I talk to patients about their p-tau217 results?

Patients often worry that a biomarker result equates to an immediate diagnosis.

We recommend framing the conversation around information, agency, and early action. Your goal is to provide reassurance and empower patients with clear next steps.

Helpful patient-centered phrases include:

• “This result helps us look ahead, not just react later.”
• “We’re catching things early, and that gives you more options.”
• “This is one part of a larger picture, and we’ll interpret it together.”

How reliable is p-tau217 compared to imaging or CSF testing?

P-tau217 aligns closely with amyloid and tau PET imaging, and studies show strong agreement with CSF biomarkers as well.

While no biomarker replaces a full diagnostic workup, p-tau217 provides a highly accurate, less invasive, and more accessible option — especially in primary care.

Its strengths are most visible in early detection scenarios, where PET or CSF might not be immediately available or necessary.

Advantages:

• High specificity for Alzheimer’s disease
• Strong PET/CSF concordance
• Cost-effective and accessible
• Non-invasive and patient-friendly

Limitations:

• Not a standalone diagnostic tool
• Should be interpreted in a clinical context
• Can be affected by rare confounders

What factors can influence or confound a p-tau217 result?

While p-tau217 is robust, several variables can influence results. These factors rarely invalidate the test but can help explain unexpected values.

Potential influences include:

• Severe systemic inflammation
• Significant vascular disease
• Certain medications or a recent acute illness
• Lab or timing variability (rare but possible)

If results seem discordant with the clinical picture, repeating the test or adding complementary markers may help clarify the signal.

How does p-tau217 fit into an early cognitive evaluation workflow?

In primary care, p-tau217 testing serves as a fast, accessible tool that slots neatly into standard evaluation steps without slowing you down.

It supports earlier differentiation between typical aging, non-Alzheimer’s conditions, and Alzheimer’s-related changes.

A typical workflow might look like:

• Initial screening (MMSE, MoCA, or patient history)
• P-tau217 testing when risk or uncertainty remains
• Supportive assessments (labs, functional evaluation)
• Neurology referral or monitoring based on results

This process creates a prevention-forward, information-rich approach to memory health.

Does a normal p-tau217 rule out Alzheimer’s disease?

A normal result lowers the likelihood of Alzheimer’s pathology but doesn’t eliminate it entirely.

Some patients may be too early in the biological process for elevation to appear, which is why we recommend continued monitoring for patients with concerns about their memory.

Consider continued monitoring when:

• Symptoms progress despite normal biomarker levels
• Strong family history persists
• Functional concerns emerge over time
• Other biomarkers or imaging remain unclear

Should I test for p-tau217 alone or with other plasma biomarkers?

P-tau217 can be highly informative on its own, but pairing it with additional biomarkers may increase clarity in ambiguous or high-risk cases.

For example, Aβ42/40 or NfL can help differentiate Alzheimer’s-related changes from other neurodegenerative or inflammatory conditions.

Combination testing may be helpful when:

• Cognitive symptoms are progressing
• Initial p-tau217 results conflict with clinical impressions
• You suspect non-Alzheimer’s neurodegeneration
• Patients request a more comprehensive prevention screen

In many scenarios, however, p-tau217 alone provides sufficient guidance.

How quickly can p-tau217 results return, and how often should I repeat them?

Turnaround times are significantly faster than those for imaging and CSF testing, and most patients typically receive plasma biomarker results within days.

Results were borderline or unexpected

Clinical changes occur over time

You’re tracking long-term risk in prevention-focused patients

How should I document or code p-tau217–related clinical decisions?

When documenting biomarker-informed decisions, clarity and context matter most.

We recommend noting the reason the test was ordered, how the results inform the assessment, and what follow-up actions you plan to take.

Standard documentation components include:

• Clinical rationale for ordering
• Summary of results in plain language
• Interpretation within the appropriate cognitive context
• Follow-up plan, monitoring, or referral intentions

Following this documentation strategy ensures continuity of care and supports clear communication across providers.

When should a patient be referred to neurology after p-tau217 testing?

P-tau217 results can guide when to escalate care. Elevated results in combination with functional decline, progressive symptoms, or complex presentations often warrant specialist evaluation.

Referral may be appropriate when:

• P-tau217 is elevated, and symptoms are persistent
• Multiple biomarkers raise concern
• Functional impairment is evident
• Follow-up plan, monitoring, or referral intentions

When your patients use Neurogen for p-tau217 testing, we include a telehealth neurologist follow-up with all qualified patients.

Bringing P-tau217 Testing Into Everyday Primary Care With Neurogen

P-tau217 testing empowers you to bring earlier clarity to memory health conversations, long before symptoms become severe. By combining a simple blood test with your clinical judgment, you can provide patients with meaningful guidance at a time when it matters most.

At Neurogen, we built our p-tau217 testing ecosystem to make prevention-forward memory care accessible, evidence-based, and easy to integrate into your workflow. Together, we can help patients take action early.

The benefits of Neurogen’s testing

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Elisabeth Thijssen, PhD

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