Diagnosis
- In order for a diagnosis of dementia to be made, cognitive impairment should be severe enough to represent a significant decline from previous level of occupational and social functioning
Diagnostic Guidelines
- Diagnosis of subtype of dementia is done by using international standard criteria
- Clinical assessment is the basis of diagnosis
- Neuropsychological testing is used when dementia is not clinically obvious
Alzheimer’s Disease
- Diagnosis of Alzheimer’s disease should be made when typical degenerative syndrome is present
- Definitive diagnosis is only confirmed on microscopic exam of the brain (usually at autopsy)
- MRI findings of hippocampal atrophy may help in the diagnosis of Alzheimer’s disease in a patient with typical clinical presentation
- Amyloid positron emission tomography (PET) scan and cerebrospinal fluid amyloid and tau levels may help in the diagnosis of Alzheimer's disease
Vascular Dementia
- Diagnosed by history, focal neurological signs and symptoms and/or imaging studies
Dementia with Lewy Bodies
- Histopathologically, Lewy inclusion bodies are present in the cerebral cortex
- May be diagnosed based on history, physical, neurological examination and functional neuroimaging studies usually MRI
Assessment
Clinical Assessment
Should include, but is not limited to, the following:
- Careful evaluation of medical, psychiatric, neurological, medication and social history
- Detailed review of cognitive and behavioral symptoms from patient and caregiver
Physical Examination
- Exclude treatable causes which may be contributing to dementia
Laboratory Tests
Diagnostic Tests
- Complete blood count (CBC), serum electrolytes, liver function test, renal function tests, glucose, thyroid function, vitamin B12 and folate levels, and syphilis serology (if syphilis is suspected)
- Neuroimaging (MRI, CT scan)
- Neuropsychological testing
Cognitive and Mental State Examination
- Montreal Cognitive Asssessment, 7-Minute Screen, Memory Impairment Screen, Mini-Mental State Exam, or Abbreviated Mental Test
- Score interpretations should also consider other factors that may affect the performance (eg educational level, social class, cultural background, literacy, language or other communication difficulties)