What are the diagnostic criteria and management options for dementia?

Diagnostic Criteria and Management Options for Dementia

The diagnosis of dementia requires evidence of cognitive or behavioral symptoms that interfere with daily functioning, represent a decline from previous levels, and are not explained by delirium or major psychiatric disorder, with assessment through history-taking and objective cognitive evaluation. 1, 2

Diagnostic Criteria

Core Clinical Criteria for Dementia Diagnosis

• Cognitive or behavioral symptoms must:

  • Interfere with ability to function at work or usual activities 1
  • Represent a decline from previous levels of functioning 1, 2
  • Not be explained by delirium or major psychiatric disorder 1
  • Be detected through history-taking from patient and knowledgeable informant, plus objective cognitive assessment 1

• Key cognitive domains affected include:

  • Memory impairment (repetitive questions, misplacing items, forgetting events) 1, 2
  • Impaired reasoning and handling of complex tasks (poor judgment, financial management difficulties) 1
  • Visuospatial abilities impairment (inability to recognize faces or common objects) 1
  • Language function impairment (difficulty finding words, hesitations in speech) 1
  • Changes in personality or behavior (mood fluctuations, apathy) 1, 2

Diagnostic Assessment Tools

• Standardized cognitive assessment tools are recommended to generate scores that can be tracked over time 1
• Commonly used screening tools include:
  • Mini-Mental State Examination (MMSE) - high sensitivity and specificity for moderate dementia 1
  • Montreal Cognitive Assessment (MoCA) - more sensitive for mild cognitive impairment 1
  • Clock Drawing Test - useful supplementary screening tool 2
  • For specialized populations (e.g., intellectual disabilities): Dementia Scale for Down's Syndrome, Dementia Questionnaire for People With Learning Disabilities 1

Diagnostic Workup

• Medical history and cognitive examination to determine existence, severity, and nature of cognitive impairment 1

• Physical examination should be comprehensive, focusing on findings that suggest underlying medical issues 1

• Laboratory tests:

  • Complete blood count, thyroid testing, and serum B12 (recommended by all guidelines) 1
  • Liver function tests, electrolytes, calcium, and glucose 1
  • Blood urea nitrogen to test kidney function 1
  • Serology testing as appropriate 1

• Neuroimaging:

  • Anatomical neuroimaging (MRI preferred over CT) recommended for:
    • Onset of cognitive symptoms within past 2 years
    • Unexpected decline in cognition/function
    • Recent significant head trauma
    • Unexplained neurological manifestations
    • Significant vascular risk factors 2, 3

Management Options

Pharmacological Interventions

• Cholinesterase inhibitors (ChEIs) are recommended for mild to moderate dementia 1, 4:

  • Donepezil for mild to severe Alzheimer's disease 4
  • Rivastigmine for Alzheimer's disease and Parkinson's disease dementia 5, 4
  • Galantamine for Alzheimer's disease 1

• Memantine:

  • Recommended for moderate to severe dementia 1, 6
  • Can be used alone or as add-on therapy with cholinesterase inhibitors 6, 4
  • Provides modest symptomatic relief 4

• Clinical trials show these medications can delay clinical decline and benefit cognitive function 1, 5, 6

Non-Pharmacological Interventions

• Non-pharmacological approaches should be prioritized, especially for behavioral and psychological symptoms of dementia 1
• Effective interventions include:
  • Cognitive training and activities (reading, playing chess) 1, 4
  • Physical exercise (walking, swimming) 1, 4
  • Music or art therapy 1
  • Reminiscence therapy 1
  • Social engagement (family gatherings) 4

Special Considerations and Pitfalls

• Rule out conditions that mimic dementia:

  • Depression (can cause symptoms similar to dementia and can co-occur with early dementia) 1
  • Metabolic disturbances (electrolyte abnormalities, B12 deficiencies, thyroid dysfunction) 1
  • Medication effects (polypharmacy, drug-drug interactions) 1
  • Sleep disorders 1

• Assessment of living conditions and support is critical when dementia is suspected:

  • Evaluate safety concerns and appropriateness of current living situation 1
  • Plan proactively for increasing needs 1

• Regular follow-up:

  • Cognitive, functional, neuropsychiatric, and behavioral symptoms should be reassessed periodically 2
  • Recommended follow-up every 6-12 months to track disease progression 2

• Caution regarding medication side effects:

  • Monitor for adverse effects of cholinesterase inhibitors and memantine 5, 6
  • In combination therapy, be aware of potential increased neurodegeneration risk (shown in animal studies) 6