From the Guidelines
Laboratory tests for dementia should include a comprehensive blood panel, thyroid function tests, vitamin B12 and folate levels, and structural brain imaging with MRI or CT scans, as recommended by the most recent guidelines 1. When evaluating patients with suspected dementia, it is essential to rule out reversible causes of cognitive decline. The following tests are recommended:
- Complete blood count
- Comprehensive metabolic panel
- Thyroid function tests (TSH, free T4)
- Vitamin B12 and folate levels
- Syphilis serology
- HIV screening in at-risk individuals
- Erythrocyte sedimentation rate
- C-reactive protein
- Lipid profile Testing for specific dementia biomarkers, such as cerebrospinal fluid analysis for amyloid-beta, tau, and phosphorylated tau proteins, may be considered in cases where Alzheimer's disease is suspected 2. Brain imaging studies, like MRI or CT scans, are crucial to identify structural abnormalities, vascular changes, or patterns of atrophy, and can help distinguish between different types of dementia, such as Alzheimer's, vascular, Lewy body, or frontotemporal dementia 3, 4, 5. Early and accurate diagnosis through appropriate laboratory testing allows for better management of symptoms and planning for future care needs.
From the Research
Laboratory Tests for Dementia
- Initial laboratory evaluation for dementia includes tests for: + Thyroid-stimulating hormone levels 6 + Vitamin B12 levels 6
- Structural neuroimaging with noncontrast computed tomography or magnetic resonance imaging is also recommended 6
- Other testing should be guided by the history and physical examination 6
- Neuropsychologic testing can help determine the extent of cognitive impairment, but it is not recommended on a routine basis 6
Additional Tests
- While not directly related to dementia, other tests that may be relevant in older adults include: + Complete blood count 7 + Basic metabolic panel 7 + Liver function tests 7 + Thyroid function tests 7 + C-reactive protein level 7 + Erythrocyte sedimentation rate 7 + Lactate dehydrogenase measurement 7 + Ferritin 7 + Protein electrophoresis 7 + Urinalysis 7 + Chest radiography 7 + Fecal occult blood testing 7