• Knopman DS, DeKosky ST, Cummings JL, Chui H, Corey-Bloom J, Relkin N, Small GW, Miller B, Stevens JC. Practice parameter: diagnosis of dementia (an evidence-based review): report of the quality standards subcommittee of the American Academy of Neurology. Neurology 2001 May 8;56(9):1143-53. [147 references]

This is the current release of the guideline.

According to the guideline developer, this guideline has been reviewed and is still considered to be current as of February 2004. This review involved new literature searches of electronic databases followed by expert committee review of new evidence that has emerged since the original publication date.

It updates a previously released version: Practice parameter for diagnosis and evaluation of dementia. Report of the Quality Standards Subcommittee of the American Academy of Neurology. Neurology 1994 Nov;44(11):2203-6.

• Dementia, including vascular dementia, dementia with Lewy bodies, and frontotemporal dementia
• Creutzfeldt-Jakob disease
• Alzheimer’s disease

Diagnosis

Family Practice
Geriatrics
Internal Medicine
Neurology
Pathology
Psychiatry
Radiology

Physicians
Psychologists/Non-physician Behavioral Health Clinicians

To update the 1994 practice parameter for the diagnosis of dementia in the elderly

Elderly patients (over age 65) undergoing an initial assessment for dementia

Use of Diagnostic Criteria for Dementia

1. Diagnostic and Statistical Manual, 3rd edition, revised (DSM-IIIR) definition of dementia and criteria for Alzheimer's disease
2. Diagnostic and Statistical Manual, 4th edition (DSM-IV) definition of dementia
3. National Institute of Neurologic, Communicative Disorder and Stroke-Alzheimer's Disease and Related disorders Association (NINCDS-ADRDA) Work Group definitions of dementia and criteria for Alzheimer's disease
4. Hachinski Ischemic Index criteria for diagnosis of cerebrovascular disease in dementia
5. Consortium for dementia with Lewy bodies diagnostic criteria
6. Consensus diagnostic criteria for frontotemporal dementia
7. Clinical criteria for Creutzfeldt-Jakob disease

Structural Neuroimaging for Differential Diagnosis of Dementing Illness (Note: linear or volumetric magnetic resonance imaging and computed tomography are considered but not recommended)

1. Noncontrast computed tomography
2. Noncontrast magnetic resonance imaging

Functional Neuroimaging (Note: these tests are considered but not recommended for routine use)

1. Single-photon emission computed tomography (SPECT)
2. Positron emission tomography (PET)

Other Laboratory Tests

1. Genetic testing, such as apolipoprotein E (APOE) genotyping, testing for tau mutations or Alzheimer's disease gene mutations (considered but not recommended)
2. Immunoassay for cerebrospinal fluid 14-3-3 protein in diagnosis of Creutzfeldt-Jakob disease
3. Other cerebrospinal fluid markers or biomarkers (considered but not recommended)

Screening for Comorbid Conditions

1. Screening for depression using validated instruments, e.g. Geriatric Depression Scale, Centers for Epidemiologic Studies Depression Scale, and Hamilton Depression Scale
2. Screening for vitamin B₁₂ deficiency
3. Screening for hypothyroidism
4. Screening for syphilis (considered but not routinely recommended)

• Reliability of current criteria for diagnosis of dementia
• Accuracy of current criteria to establish diagnosis for the prevalent dementias
• Accuracy of laboratory tests in the clinical diagnosis of dementia (sensitivity, specificity, positive predictive value of tests)
• Incidence of comorbidities in elderly patients undergoing initial assessment for dementia

Hand-searches of Published Literature (Primary Sources)
Hand-searches of Published Literature (Secondary Sources)
Searches of Electronic Databases

Literature review process. A literature search was conducted using MEDLINE, Excerpta Medica, and BIOSIS. The search included articles published from January 1985 through November 1999. The search strategy sought only studies published in English and studies on human disease. The principal search term was dementia. Other terms entered into the search included neuroimaging, diagnostic techniques, diagnostic imaging, biologic markers, cerebrospinal fluid, diagnostic errors, differential diagnosis, and neuropsychologic tests. The original search yielded 1,175 articles of which approximately 300 articles were identified as relevant to the search questions. For articles on Alzheimer’s disease, the authors of the guideline included only those based on more than 25 patients. For the less common dementias, there was no minimal sample size. An additional 300 articles not identified by the literature search strategy, including ones published after the initial search was conducted, were submitted by committee members or obtained from bibliographies of articles identified in the search.

300

Weighting According to a Rating Scheme (Scheme Given)

Classification of Evidence

1. Evidence provided by a well-designed prospective study in broad spectrum of persons with the suspected condition, using a "gold standard" for case definition, in which test is applied in a blinded evaluation, and enabling the assessment of appropriate tests of diagnostic accuracy.
2. Evidence provided by a well-designed prospective study of a narrow spectrum of persons with the suspected condition, or a well designed retrospective study of a broad spectrum of persons with an established condition (by "gold standard") compared with a broad spectrum of controls, in which test is applied in blinded evaluation, and enabling the assessment of appropriate tests of diagnostic accuracy.
3. Evidence provided by a retrospective study in which either persons with the established condition or controls are of a narrow spectrum, and in which test is applied in a blinded evaluation.
4. Any design in which test is not applied in blinded evaluation OR evidence provided by expert opinion alone or in descriptive case series (without controls).

Review of Published Meta-Analyses
Systematic Review

Not applicable

Not stated

Definitions for Practice Recommendations Based on Classification of Evidence

Standard. Principle for patient management that reflects a high degree of clinical certainty (usually this requires Class I evidence that directly addresses the clinical question, or overwhelming Class II evidence when circumstances preclude randomized clinical trials).

Guideline. Recommendation for patient management that reflects moderate clinical certainty (usually this requires Class II evidence or a strong consensus of Class III evidence).

Practice Option. Strategy for patient management for which the clinical utility is uncertain (inconclusive or conflicting evidence or opinion).

Practice Advisory. Practice recommendation for emerging and/or newly approved therapies or technologies based on evidence from at least one Class I study. The evidence may demonstrate only a modest statistical effect or limited (partial) clinical response, or significant cost–benefit questions may exist. Substantial (or potential) disagreement among practitioners or between payers and practitioners may exist.

A formal cost analysis was not performed and published cost analyses were not reviewed.

External Peer Review
Internal Peer Review

In addition to the review and final approval by the Quality Standards Subcommittee and the Practice Committee of the American Academy of Neurology, this Practice Parameter was reviewed by American Academy of Neurology members who had identified themselves as interested reviewers, by the Geriatric and Behavioral Neurology Sections of the American Academy, by representatives of the American Geriatrics Society, and by representatives of the Alzheimer’s Association.

Classification of evidence ratings, I-IV, and the definitions for practice recommendations based on classification of evidence (Standard, Guideline, Practice Option, Practice Advisory) are defined at the end of the "Major Recommendations" field.

Diagnostic Criteria

Are the current criteria for the diagnosis of dementia reliable?

• The Diagnostic and Statistical Manual, 3rd edition, revised (DSM-III-R) definition of dementia, which is identical to Diagnostic and Statistical Manual, 4th edition (DSM-IV) definition, is reliable and should be used routinely (Guideline).

Are current diagnostic criteria able to establish a diagnosis for the prevalent dementias (Alzheimer’s disease, vascular dementia, dementia with Lewy bodies, frontotemporal dementia, prion diseases)?

• The National Institute of Neurologic, Communicative Disorders and Stroke–Alzheimer’s disease and Related Disorders Association (NINCDS-ADRDA) for the diagnosis of probable Alzheimer's disease or the Diagnostic and Statistical Manual, 3rd edition, revised (DSM-III-R) criteria for dementia of the Alzheimer's type (DAT) should be routinely used (Guideline).
• The Hachinski Ischemic Index criteria may be of use in the diagnosis of cerebrovascular disease in dementia (Option).
• The Consortium for dementia with Lewy bodies (DLB) diagnostic criteria may be of use in clinical practice (Option).
• The Consensus diagnostic criteria for frontotemporal dementia (FTD) may be of use in clinical practice (Option).
• Clinical criteria for Creutzfeldt-Jakob disease (CJD) should be used in rapidly progressive dementia syndromes (Guideline).

Laboratory Tests

Do laboratory tests improve the accuracy of clinical diagnosis of dementing illness?

• Structural neuroimaging with either a noncontrast computed tomography or magnetic resonance scan in the initial evaluation of patients with dementia is appropriate. (Guideline).
• Linear or volumetric magnetic resonance or computed tomography measurement strategies for the diagnosis of Alzheimer's Disease and are not recommended for routine use at this time (Guideline).
• For patients with suspected dementia, single photon emission computed tomography (SPECT) cannot be recommended for routine use in either initial or differential diagnosis as it has not demonstrated superiority to clinical criteria (Guideline).
• Positron emission tomography (PET) imaging is not recommended for routine use in the diagnostic evaluation of dementia at this time (Guideline).
• Genetic testing of patients with suspected dementia with Lewy bodies and Creutzfeldt-Jakob disease is not recommended (Guideline).
• Routine use of apolipoprotein E (APOE) genotyping in patients with suspected Alzheimer's disease is not recommended at this time (Guideline).
• There are no other genetic markers recommended for routine use in the diagnosis of Alzheimer’s disease (Guideline).
• Testing for tau mutations or Alzheimer's disease gene mutations is not recommended for routine evaluation in patients with frontotemporal dementia at this time (Guideline).
• There are no cerebrospinal fluid or other biomarkers recommended for routine use in determining the diagnosis of Alzheimer's disease at this time (Guideline).
• The cerebrospinal fluid 14-3-3 protein is useful recommended for confirming or rejecting the diagnosis of Creutzfeldt–Jakob disease in clinically appropriate circumstances (Guideline).

Screening for Comorbid Diseases

What comorbidities should be screened for in elderly patients undergoing an initial assessment for dementia?

• Depression is a common, treatable comorbidity in patients with dementia and should be screened for (Guideline).
• B₁₂ deficiency is common in the elderly, and B₁₂ levels should be included in routine assessments of the elderly. (Guideline).
• Because of its frequency, hypothyroidism should be screened for in elderly patients. (Guideline).
• Unless the patient has some specific risk factor or evidence of prior syphilitic infection, or resides in one of the few areas in the United States with high numbers of syphilis cases, screening for the disorder in patients with dementia is not justified (Guideline).

Definitions:

Classification of Evidence

1. Evidence provided by a well-designed prospective study in broad spectrum of persons with the suspected condition, using a "gold standard" for case definition, in which test is applied in a blinded evaluation, and enabling the assessment of appropriate tests of diagnostic accuracy.
2. Evidence provided by a well-designed prospective study of a narrow spectrum of persons with the suspected condition, or a well designed retrospective study of a broad spectrum of persons with an established condition (by "gold standard") compared with a broad spectrum of controls, in which test is applied in blinded evaluation, and enabling the assessment of appropriate tests of diagnostic accuracy.
3. Evidence provided by a retrospective study in which either persons with the established condition or controls are of a narrow spectrum, and in which test is applied in a blinded evaluation
4. Any design in which test is not applied in blinded evaluation OR evidence provided by expert opinion alone or in descriptive case series (without controls).

Practice Recommendations Based on Classification of Evidence

Standard. Principle for patient management that reflects a high degree of clinical certainty (usually this requires Class I evidence that directly addresses the clinical question, or overwhelming Class II evidence when circumstances preclude randomized clinical trials).

Guideline. Recommendation for patient management that reflects moderate clinical certainty (usually this requires Class II evidence or a strong consensus of Class III evidence).

Practice Option. Strategy for patient management for which the clinical utility is uncertain (inconclusive or conflicting evidence or opinion).

Practice Advisory. Practice recommendation for emerging and/or newly approved therapies or technologies based on evidence from at least one Class I study. The evidence may demonstrate only a modest statistical effect or limited (partial) clinical response, or significant cost–benefit questions may exist. Substantial (or potential) disagreement among practitioners or between payers and practitioners may exist.

None provided

The recommendations are based on a review of the literature. The type of supporting evidence is identified and graded for each recommendation on the diagnosis of dementia.

• Appropriate use of diagnostic criteria and laboratory tests for dementia
• Appropriate recognition and treatment of depression, B₁₂ deficiency, and hypothyroidism, which are common comorbid conditions in elderly patients with dementia

Not stated

• The statement of this guideline is provided as an educational service of the American Academy of Neurology. It is based on an assessment of current scientific and clinical information. It is not intended to include all possible proper methods of care for a particular neurologic problem or all legitimate criteria for choosing to use a specific procedure. Neither is it intended to exclude any reasonable alternative methodologies. The American Academy of Neurology recognizes that specific patient care decisions are the prerogative of the patient and the physician caring for the patient, based on all of the circumstances involved.
• The purpose of the current practice parameter is to highlight and to update major areas of current interest and investigation in the diagnosis of dementia in the elderly. It is not intended to serve as a comprehensive review of the differential diagnosis of dementia.

An implementation strategy was not provided.

Getting Better
Living with Illness

Effectiveness

• Knopman DS, DeKosky ST, Cummings JL, Chui H, Corey-Bloom J, Relkin N, Small GW, Miller B, Stevens JC. Practice parameter: diagnosis of dementia (an evidence-based review): report of the quality standards subcommittee of the American Academy of Neurology. Neurology 2001 May 8;56(9):1143-53. [147 references]

Not applicable: Guideline was not adapted from another source.

2001 May (reviewed 2004)

American Academy of Neurology - Medical Specialty Society

American Academy of Neurology (AAN)

Quality Standards Subcommittee

Authors: D.S. Knopman, MD; S.T. DeKosky, MD; J.L. Cummings, MD; H. Chui, MD; J. Corey-Bloom, MD, PhD; N. Relkin, MD, PhD; G.W. Small, MD; B. Miller, MD; and J.C. Stevens, MD

Committee members disclosed any real or potential conflicts of interest.

American Association of Neuroscience Nurses - Professional Association
American Geriatrics Society - Medical Specialty Society

This is the current release of the guideline.

According to the guideline developer, this guideline has been reviewed and is still considered to be current as of February 2004. This review involved new literature searches of electronic databases followed by expert committee review of new evidence that has emerged since the original publication date.

It updates a previously released version: Practice parameter for diagnosis and evaluation of dementia. Report of the Quality Standards Subcommittee of the American Academy of Neurology. Neurology 1994 Nov;44(11):2203-6.

This NGC summary was completed by ECRI on February 12, 2002. The information was verified by the guideline developer on September 5, 2003.

This NGC summary is based on the original guideline, which is copyrighted by the American Academy of Neurology.