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Pathologies and the Use of Cerebrospinal-Fluid-Based Biomarkers in Alzheimer Disease

  • Authors: Marwan N. Sabbagh, MD, FAAN; Carrie V. Vause, MS; Jane M. Caldwell, PhD
  • CME / CE Released: 3/13/2023
  • Valid for credit through: 3/13/2024
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  • Credits Available

    Physicians - maximum of 1.00 AMA PRA Category 1 Credit(s)™

    Nurses - 1.00 ANCC Contact Hour(s) (0 contact hours are in the area of pharmacology)

    Physician Assistant - 1.00 AAPA hour(s) of Category I credit

    You Are Eligible For

    • Letter of Completion

Target Audience and Goal Statement

This activity was developed for physicians, physician assistants, and nurses involved in primary care, neurology, and internal medicine, or other healthcare providers involved in the diagnosis of patients with Alzheimer disease.

Dementia poses a significant economic burden to healthcare systems and society, with over 50 million people currently affected. Disease progression can take many years and no cure is available. Alzheimer disease (AD) is believed to account for 60% to 80% of dementia cases. The yearly cost of AD and other dementias in the United States is predicted to increase to over $1 trillion by 2050.

 AD is a neurodegenerative disease with cognitive, functional, and behavioral impairments. It is characterized by the progressive accumulation of extracellular amyloid beta (Aβ) plaques and intracellular neurofibrillary tangles (NFTs). Up to 30 years ahead of symptoms onset, there may be evidence of AD pathology in the form of Aβ or NFTs, but not of cognitive decline. Early diagnosis can give patients an opportunity to plan ahead. Previous methods of AD diagnosis include postmortem autopsies, costly amyloid positron emission tomography (PET) scans, and unreliable clinical behavioral assessments.

 Biomarkers provide a rapid, less expensive, and more quantitative method of diagnosis. Some cerebrospinal fluid (CSF) biomarkers are reliably associated with AD pathology and may provide additional information in clinical diagnosis. Markers such as CSF Aβ42/Aβ40 are concordant with amyloid PET scans and show promise in the detection of AD. Other markers, both CSF and plasma, may also be useful with perspective given to racial disparities and PET concordance.

 This educational article will review the neurobiological basis of Alzheimer disease, identify the role of CSF biomarkers in establishing a diagnosis, and discuss racial disparities seen in AD biomarkers.

Upon completion of this activity, participants will be able to:

  1. Review current theories on the neurobiological basis for AD
  2. Identify the role of CSF biomarkers in establishing the diagnosis of AD
  3. Evaluate racial differences in AD biomarkers


Educational Review Systems requires every individual in a position to control educational content to disclose all financial relationships with ineligible companies that have occurred within the past 24 months. Ineligible companies are organizations whose primary business is producing, marketing, selling, re-selling, or distributing healthcare products used by or on patients.

All relevant financial relationships for anyone with the ability to control the content of this educational activity are listed below and have been mitigated according to Educational Review Systems policies. Others involved in the planning of this activity have no relevant financial relationships.


  • Marwan N. Sabbagh, MD, FAAN

    Professor, Department of Neurology
    Barrow Neurological Institute
    Phoenix, Arizona


    Marwan N. Sabbagh, MD, FAAN, has the following relevant financial relationships:
    Consultant or advisor for: Biogen; Corium; Eisai; Genentech/Roche; Lilly; Neuro Therapia Prothena; Signant;T3D Therapeutics
    Speaker or member of speakers bureau for: Lilly
    Research funding from: Alzheimer's Drug Discovery Foundation; NIH
    Royalties from: Humanix
    Patent beneficiary of: Humanix
    Stock options from: Alzheon; Athira Pharma; Lighthouse; NeuroTau; Quince
    Other: Board of Directors, EIP Pharma

  • Jane M. Caldwell, PhD

    Science and Health Writer
    Springfield, Missouri


    Jane M. Caldwell, PhD, has no relevant financial relationships.

  • Carrie V. Vause, MS

    Director of Content Development
    Medavera Inc.
    Richland, Missouri


    Carrie V. Vause, MS, has no relevant financial relationships.

Accreditation Statements

Jointly provided by Educational Review Systems and Your CE Source.

ACCME credits are jointly provided by Educational Review Systems and Your CE Source. This activity has been planned and implemented in accordance with the Essential Areas and Policies of the Accreditation Council for Continuing Medical Education through Your CE Source. Your CE Source is accredited by the ACCME to provide continuing medical education for physicians.

Educational Review Systems is an approved provider of continuing education in nursing by ASNA, an accredited provider by the ANCC/Commission on Accreditation (provider #5-115) and by the American Academy of PAs (AAPA).

    For Physicians

  • Your CE Source designates this live activity for a maximum of 1.0 AMA PRA Category 1 Credit(s)™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.

    For Nurses

  • Awarded 1.0 contact hour(s) of continuing nursing education for RNs and APNs; 0.00 contact hours are in the area of pharmacology.

  • For Physician Assistants

    Educational Review Systems has been authorized by the American Academy of PAs (AAPA) to award AAPA Category 1 CME credit for activities planned in accordance with AAPA CME Criteria. This activity is designated for ​1.00​ AAPA Category 1 CME credits. Approval is valid until ​March 13, 2024​. PAs should only claim credit commensurate with the extent of their participation.

For questions regarding the content of this activity, contact the accredited provider for this CME/CE activity noted above. For technical assistance, contact [email protected]

Instructions for Participation and Credit

There are no fees for participating in or receiving credit for this online educational activity. For information on applicability and acceptance of continuing education credit for this activity, please consult your professional licensing board.

This activity is designed to be completed within the time designated on the title page; physicians should claim only those credits that reflect the time actually spent in the activity. To successfully earn credit, participants must complete the activity online during the valid credit period that is noted on the title page. To receive AMA PRA Category 1 Credit™, you must receive a minimum score of 80% on the post-test.

Follow these steps to earn CME/CE credit*:

  1. Read about the target audience, learning objectives, and author disclosures.
  2. Study the educational content online or print it out.
  3. Online, choose the best answer to each test question. To receive a certificate, you must receive a passing score as designated at the top of the test. We encourage you to complete the Activity Evaluation to provide feedback for future programming.

You may now view or print the certificate from your CME/CE Tracker. You may print the certificate, but you cannot alter it. Credits will be tallied in your CME/CE Tracker and archived for 6 years; at any point within this time period, you can print out the tally as well as the certificates from the CME/CE Tracker.

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Pathologies and the Use of Cerebrospinal-Fluid-Based Biomarkers in Alzheimer Disease

Authors: Marwan N. Sabbagh, MD, FAAN; Carrie V. Vause, MS; Jane M. Caldwell, PhDFaculty and Disclosures

CME / CE Released: 3/13/2023

Valid for credit through: 3/13/2024



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