ModifiedEmblemHealthPolicy AHS-G2048

Biochemical Markers of Alzheimer Disease and Dementia - Lab Benefit Program (LBM)

Governs coverage and reimbursement for laboratory tests measuring biochemical biomarkers related to Alzheimer disease and dementia for EmblemHealth members under the Lab Benefit Program; specifies which CSF and plasma biomarker tests meet or do not meet coverage criteria and notes applicability depends on individual benefit coverage.

Policy Summary

PayerEmblemHealth

PolicyBiochemical Markers of Alzheimer Disease and Dementia - Lab Benefit Program (LBM)

Policy CodePolicy AHS-G2048

Change TypeCoverage criteria and coding updates (edits, additions, removals)

Effective DateMar 1, 2023

Next Review Date

Key ActionConfirm patient benefit coverage and apply coding/billing guidelines when ordering CSF or FDA‑approved plasma biomarker tests; follow diagnostic follow-up rules for incongruent results.

SourceLink

POLICY UPDATE CHANGES

Coverage Criteria 2 added to allow p-tau/AB42 ratio measurement in plasma.

Coverage Criteria 1 edited to allow p-tau/AB42 and t-tau/AB42 ratio in CSF.

Former Coverage Criteria 2 and 3 were renumbered and edited to align with the new allowances.

Several CPT codes (82233, 82234, 83884, 84393, 84394) were added following coding modifications effective 1/1/2025.

Multiple PLA/other CPT codes (0206U, 0207U, 0289U, 0346U, 0393U, 0412U, 0443U, 0445U, 0459U, 0547U, 0551U, 0548U) were removed.

Lab Benefit Program (LBM) expanded to include EmblemHealth HMO/PPO (Non-City), Medicare and Medicaid plans effective 10/1/2024.

3CSF categories covered

Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.

FDA‑approved plasma ratio

>=1Latest coverage edits

Coverage Criteria and Clinical Guidance

Coverage criteria and exclusions

Coverage determinations for biomarker testing in individuals with suspected Alzheimer disease or mild cognitive impairment:

ALL of the following

Amyloid beta peptides (CSF)
MEETS COVERAGE CRITERIA for individuals with suspected Alzheimer disease or mild cognitive impairment.
Ratio of total tau (t-tau) to amyloid beta 1-42 (Aβ42) (CSF)
MEETS COVERAGE CRITERIA for individuals with suspected Alzheimer disease or mild cognitive impairment.
Ratio of phosphorylated tau 181 (p-tau181) to Aβ42 (CSF)
MEETS COVERAGE CRITERIA for individuals with suspected Alzheimer disease or mild cognitive impairment.

ALL of the following

Ratio of p-tau217 to Aβ42 in plasma using an FDA-approved test (e.g., Lumipulse G pTau217/ß-Amyloid 1-42 Plasma Ratio)
MEETS COVERAGE CRITERIA when performed with an FDA-approved assay.

ANY of the following

CSF biomarkers not specifically listed above (e.g., α-synuclein, neural thread proteins)
DOES NOT MEET COVERAGE CRITERIA due to lack of published evidence.
Plasma or serum biomarkers not specifically listed (e.g., individual p-tau217 or Aβ42 alone, total tau, Aβ40, ApoE/ApoE4)
DOES NOT MEET COVERAGE CRITERIA.
Urinary biomarkers (e.g., neural thread proteins, amyloid peptides, urinary extracellular vesicle analysis)
DOES NOT MEET COVERAGE CRITERIA.
Multianalyte assays, algorithmic analyses, or other tests not specifically listed
DOES NOT MEET COVERAGE CRITERIA.

Coverage-related clinical criteria (guideline-aligned)

Guideline-derived stance on use of blood-based biomarkers (BBMs) and CSF biomarkers for AD diagnosis and staging.

ALL of the following

BBMs with established thresholds should currently only be used in symptomatic patients at specialist memory clinics
Results should be confirmed with CSF or PET whenever possible; additional data needed before BBMs are used as standalone diagnostic markers.

ALL of the following

BBMs are not recommended for routine use in primary care
Additional data required before recommending BBMs for general practice; may be used cautiously as screeners for trials but not as standalone diagnostics.

ALL of the following

Specific Core 1 biomarkers (amyloid PET; CSF Aβ42/40; CSF p-tau181/Aβ42; CSF t-tau/Aβ42; or 'accurate' plasma assays equivalent to CSF assays) can be sufficient to establish a diagnosis of AD in appropriate clinical contexts

Biomarker coverage and interpretation criteria

Recommendations and decision framework for biomarker testing and interpretation by clinical phenotype and amyloid/tau result combinations

ALL of the following

Prioritize CSF investigation for simultaneous amyloid and tau information (preferred over PET when available)
If lumbar puncture is contraindicated, consider amyloid PET or tau PET as alternatives

ALL of the following

Plasma biomarkers for amyloid β and tau are not currently recommended for routine clinical practice
Require further standardization and validation before broad clinical use

ALL of the following

Summary of recent coverage edits

Revision History summarizes substantive coverage changes; exact criteria language and detailed eligibility rules are not included in these chunks.

ALL of the following

Coverage Criterion 1 edited to allow p-tau/AB42 and t-tau/AB42 ratio in CSF
New Coverage Criterion 2 added to allow p-tau/AB42 ratio measurement in plasma
Former Coverage Criteria 2 and 3 renumbered to Coverage Criteria 3 and 4 and edited to align with new allowances

Coding, Claims Editing, and Code Lists

Applicable coding and claims editing guidancemixed

No codes listed

No specific CPT/HCPCS/ICD codes listed in this excerptmixed

No codes listed

Listed procedure codesCPT

82233	Beta-amyloid; 1-40 (Abeta 40)
82234	Beta-amyloid; 1-42 (Abeta 42)
83520	Immunoassay for analyte other than infectious agent antibody or infectious agent antigen; quantitative, NOS
83884	Neurofilament light chain (NfL)
84393	Tau, phosphorylated (eg, pTau 181, pTau 217), each
84394	Tau, total (tTau)
0358U	Neurology (mild cognitive impairment), analysis of β-amyloid 1-42 and 1-40, chemiluminescence enzyme immunoassay, cerebrospinal fluid; Proprietary test: Lumipulse® G β-Amyloid Ratio (1-42/1-40) (Fujirebio Diagnostics, Inc)

Added CPT codesCPTCovered

82233	CPT code added (policy revision)
82234	CPT code added (policy revision)
83884	CPT code added (policy revision)
84393	CPT code added (policy revision)
84394	CPT code added (policy revision)

Removed CPT/PLA codesCPTNot Covered

0206U	Removed
0207U	Removed
0289U	Removed
0346U	Removed
0393U	Removed
0412U	Removed
0443U	Removed
0445U	Removed
0459U	Removed
0547U	Removed

1–10 of 12

1/2

Use restriction for blood-based biomarkers (BBMs)

RestrictionBBMs with established thresholds should currently only be used in symptomatic patients at specialist memory clinics and results should be confirmed with CSF or PET when possible.

Primary care useAdditional data are needed before BBMs can be recommended for routine use in primary care; not recommended as standalone diagnostics.

Confirmation requirementBBM results should be confirmed whenever possible with CSF or PET to support diagnostic decisions.

Preferred biomarker measures

Preferred amyloid CSF measureCSF Aβ42 is recommended; when possible Aβ40/Aβ42 ratio is preferred to low CSF Aβ42 alone.

Provider Actions, Billing Considerations, and Operational Notes

Prior Authorization

Coverage and billing considerations

Prior authorization may be required for certain biomarker panel tests under the Lab Benefit Program (LBM). Verify member eligibility and benefit coverage, and obtain any required authorizations before specimen collection. Claims submitted without appropriate prior authorization or documentation may be denied or subject to recoupment.

Affected codes: see Applicable CPT/HCPCS Procedure Codes table in policy header and Revision/Coding Updates below.
Confirm product-specific LBM applicability (Commercial, Medicare, Medicaid) and effective dates before ordering.
Maintain clear documentation of clinical indication, cognitive assessment, and prior authorizations in the medical record.

Billing Rule

Reimbursement Policy (operational summary)

Definitions and Abbreviations

CSF

TermCSF = Cerebrospinal fluid

ContextCSF testing provides simultaneous information on amyloid β and tau pathology and is prioritized over PET when appropriate.

Use noteCSF biomarkers (Aβ42/Aβ40, p-tau/Aβ42 ratios) are among measures that meet coverage criteria when used per policy rules.

p-tau

Termp-tau = Phosphorylated tau

Preferred useCSF phosphorylated tau (eg, p-tau181, p-tau217) is recommended for assessing tau pathology; plasma p-tau assays require further validation for routine clinical use.

Diagnostic role

Policy Summary

PayerEmblemHealth

PolicyBiochemical Markers of Alzheimer Disease and Dementia - Lab Benefit Program (LBM)

Policy CodePolicy AHS-G2048

Change TypeCoverage criteria and coding updates (edits, additions, removals)

Effective DateMar 1, 2023

Next Review Date

Key ActionConfirm patient benefit coverage and apply coding/billing guidelines when ordering CSF or FDA‑approved plasma biomarker tests; follow diagnostic follow-up rules for incongruent results.

SourceLink

On This Page

Not all available Core 1 tests have sufficient accuracy; validated Core 1 assays should be used.

ALL of the following

CSF and plasma assays may exhibit analytic and preanalytic variability leading to misclassification
Standardization and further validation are needed before broader clinical adoption.

ALL of the following

Follow Alzheimer’s Association guidance on appropriate versus inappropriate indications (e.g., appropriate for persistent/progressive MCI; inappropriate for cognitively unimpaired low-risk individuals)
Use clinical judgment and guideline-listed indications when ordering CSF tests.

Physicians should evaluate added value of biomarker testing for each symptomatic patient considering age, comorbidity, phenotype complexity, patient preferences, trial eligibility, and impact on management

Limit investigations based on availability, cost, and coverage

ALL of the following

Amyloid positive & tau positive => Highly probable/established AD; further investigation required
Amyloid positive & tau unknown => Probable AD; consider tau measure (PET or CSF)
Amyloid positive & tau negative => Probable; consider additional tau measure (PET or CSF)
Amyloid negative & tau unknown/negative => Unlikely or highly unlikely AD; perform full investigation of cause and consider complementary measures

ALL of the following

Amyloid unknown & tau unknown => Non-assessable; consider both amyloid and tau measures (PET, CSF)
Incongruent phenotype and neurodegeneration patterns should prompt re-investigation

Preferred tau CSF measureCSF phosphorylated tau (p-tau) is recommended for tau pathology; total tau is not recommended due to low specificity.

PET alternativeIf lumbar puncture is contraindicated, consider amyloid PET or tau PET as alternatives.

Coding effective date

Coding effective date2025-01-01 (coding modifications added CPT codes effective 1/1/2025).

Revision noteCoding table updates and CPT code additions/removals documented in Revision History (see effective dates).

Policy effective headerPolicy effective date provided in document header (3/01/2023) but coding change effective 1/1/2025.

This policy is a Reimbursement Policy for Biochemical Markers of Alzheimer Disease and Dementia within the EmblemHealth Lab Benefit Program (LBM). Billing must follow current CPT/HCPCS coding, CMS NCCI/MUE edits, and payer-specific claims edits. When coding guidance conflicts across sources, EmblemHealth will apply the edits it determines appropriate. Failure to follow applicable coding/billing guidelines may result in denial or recoupment.

Use the Applicable CPT/HCPCS Procedure Codes listed in the policy when submitting claims.
Ensure correct specimen source modifiers and any required CSF/plasma specimen documentation are included on the claim.
Requests for member-specific reimbursement rationale or coding explanations can be made to EmblemHealth through provider inquiry channels.

Documentation Required

Diagnostic follow-up rules

Results from amyloid and tau biomarkers must be interpreted in the context of clinical presentation and other diagnostic studies. Positive or inconclusive biomarker findings generally require diagnostic follow-up as described below to guide diagnosis and management.

Amyloid positive + tau positive: consider diagnosis of Alzheimer’s disease very likely; further investigation or specialty referral may be required for care planning.
Amyloid positive + tau unknown/negative: consider additional tau measurement (CSF or PET) when results would change management.
Tau positive + amyloid unknown/negative: consider additional amyloid measurement (CSF or PET) to clarify likelihood of Alzheimer’s disease.
Amyloid negative or tau negative with discordant clinical picture: perform full investigation for alternative causes of cognitive impairment and consider referral to neurology or memory disorders specialist.

Note

Revision and coding updates

Coding and coverage determinations are updated periodically. Providers must bill using current effective CPT/HCPCS codes and modifiers. EmblemHealth posts coding updates and effective dates on the Reimbursement Policies webpages and in provider communications.

Recent and upcoming code changes (examples): added CPT 82233, 82234, 83884, 84393, 84394; removed select PLA codes (0206U, 0207U, 0289U, 0346U, 0393U, 0412U, 0443U, 0445U, 0459U, 0547U, 0551U, 0548U) per 1/1/2025 coding modifications.
Effective date changes and coverage-criteria edits (see Revision History) may alter which biomarkers or specimen types are reimbursed — verify the policy effective date before billing.
When new biomarker ratios or specimen matrices (e.g., plasma p-tau/AB42 ratio) are added to coverage criteria, ensure laboratory reports and claims reflect the measurable analyte and method.

p-tau in CSF (eg p-tau181) used in Core 1 biomarker panels (eg p-tau/Aβ42 ratio) to help diagnose AD.

t-tau

Termt-tau = Total tau

SpecificityTotal tau is not recommended alone for tau pathology due to low specificity; t-tau/Aβ42 ratio is allowed in CSF per policy updates.

Coding noteCPT code 84394 corresponds to Tau, total (tTau) in applicable code list.

Core 1 and Core 2 biomarkers

Core 1 definitionCore 1 biomarkers (A and T1) become abnormal around the same time as amyloid PET and an abnormal Core 1 biomarker result can be sufficient to establish an AD diagnosis.

Core 1 examplesExamples include amyloid PET; CSF Aβ42/40; CSF p-tau181/Aβ42; CSF t-tau/Aβ42; or accurate plasma assays equivalent to approved CSF assays.

Core 2 roleCore 2 biomarkers (eg MTBR-tau243, other phosphorylated tau forms, tau PET) provide prognostic information and are generally not standalone diagnostic tests.

Appropriate clinical indications for CSF testing

Appropriate indicationsAlzheimer's Association recommends CSF testing for specific clinical indications (eg persistent/progressive MCI) rated as Appropriate.

Inappropriate useCSF biomarker investigation is not recommended in cognitively unimpaired low-risk individuals (rated Inappropriate).

Quality controlMeasurements of CSF AD biomarkers show large between-laboratory variability; standardization efforts are needed to improve usefulness.

Amyloid biomarker

DefinitionAmyloid biomarker = CSF Aβ42 or CSF Aβ40/Aβ42 ratio; amyloid PET is an imaging alternative.

Preferred measureCSF Aβ40/Aβ42 ratio preferred when possible over low CSF Aβ42 alone for amyloid pathology detection.

CPT mappingCPT codes 82233 (Aβ40) and 82234 (Aβ42) are listed in the applicable procedure codes.

Tau biomarker

DefinitionTau biomarker = CSF phosphorylated tau (p-tau); total tau has low specificity and is less preferred.

Recommended measureUse CSF p-tau (eg p-tau181, p-tau217) or tau PET for tau pathology assessment.

Coding noteCPT code 84393 corresponds to phosphorylated tau (eg pTau181, pTau217) in the procedure code list.

LDT / FDA-cleared assays

LDTsLaboratory-developed tests (LDTs) are validated and performed in-house under CLIA; they are not FDA-approved but may be used clinically.

FDA-clearancesSeveral assays have received FDA marketing/clearance (eg Fujirebio Lumipulse CSF Aβ ratio, Roche Elecsys CSF pTau181/Abeta42 and tTau assays).

Regulatory noteFDA clearance/approval is not currently required for clinical use of LDTs; CMS regulates LDTs under CLIA '88 as high-complexity tests.

Biomarker ratio measurements now allowed

Allowed CSF ratios (policy update)p-tau/AB42 and t-tau/AB42 ratios in CSF are explicitly allowed following the revision (effective 2/13/2026 edits).

Allowed plasma ratio (new)Policy added allowance for p-tau/AB42 ratio measurement in plasma (new Coverage Criterion 2, revision noted).

ContextThese ratio measurements were added to align CSF and plasma biomarker interpretations and follow guideline recommendations preferring ratio measures.