From the Guidelines
To obtain a dementia diagnosis, start by scheduling an appointment with a primary care physician who will conduct an initial evaluation and may refer you to a specialist such as a neurologist, geriatrician, or geriatric psychiatrist. The diagnostic process typically involves a comprehensive assessment including a detailed medical history, cognitive tests like the Mini-Mental State Examination (MMSE) or Montreal Cognitive Assessment (MoCA), physical examination, neurological tests, laboratory tests (blood work to rule out vitamin deficiencies, thyroid problems, or infections), and brain imaging such as MRI or CT scans 1.
Key Steps in the Diagnostic Process
- Obtain an expanded history focused on cognitive abilities to include onset of complaint, pace of decline, and nature of cognitive loss
- Conduct a neurologic physical examination
- Assess risk factors for cognitive decline and medications that may contribute to cognitive impairment
- Assess for psychiatric conditions
- Request general labs including thyroid function tests, vitamin B12, homocysteine, complete blood count with differential, complete metabolic panel, erythrocyte sedimentation rate, and C-reactive protein
- Perform structural brain imaging with MRI (head CT if MRI contraindicated) 1
Importance of Early Diagnosis
Early diagnosis is crucial as it allows for appropriate treatment planning, access to medications that may temporarily improve symptoms, participation in clinical trials, and time to make legal, financial, and care planning decisions while the person with dementia can still participate in the process 1.
Role of Biomarkers
Biomarkers such as reduced levels of the 42-amino-acid form of amyloid-b (Ab1–42) and elevated levels of tau and phosphorylated tau (p-tau) in the cerebrospinal fluid (CSF) can be used to increase the certainty that the underlying cause of a dementia syndrome is Alzheimer's disease 1.
Comprehensive Assessment
A comprehensive assessment is essential for an accurate diagnosis, and family members should attend appointments to provide additional information about observed cognitive changes. Be prepared to discuss symptoms thoroughly, including when they began, how they've progressed, and how they affect daily functioning. The evaluation may require multiple appointments over several weeks 1.
From the Research
Obtaining a Dementia Diagnosis
- Dementia diagnosis requires a comprehensive evaluation, including a thorough medical history, physical examination, and cognitive assessment 2, 3.
- A clinical history, evaluating for cognitive decline and impairment in daily activities, with corroboration from a close friend or family member, is essential for diagnosing dementia 2.
- Brief cognitive impairment screening questionnaires can assist in initiating and organizing the cognitive assessment, while neuropsychological testing can help determine whether dementia is present if the assessment is inconclusive 2, 4.
- Physical examination may help identify the etiology of dementia, and brain neuroimaging can demonstrate structural changes, such as focal atrophy, infarcts, and tumor, that may not be identified on physical examination 2, 4.
- Additional evaluation with cerebrospinal fluid assays or genetic testing may be considered in atypical dementia cases, such as age of onset younger than 65 years, rapid symptom onset, and/or impairment in multiple cognitive domains but not episodic memory 2.
Diagnostic Evaluation
- A standard diagnostic evaluation can be performed by family physicians over multiple visits, involving a clinical history, physical examination, and brief cognitive testing 4.
- Structural imaging with computed tomography or magnetic resonance imaging is recommended in selected cases to rule out treatable causes of dementia or to rule in cerebrovascular disease 4.
- Validated cognitive assessment tools can help clinicians identify the extent and nature of cognitive deficits and track disease progression over time 3.
- Advances in the field of dementia research, such as serum biomarkers, are showing promise in facilitating an earlier and more accurate diagnosis 3.
Algorithm for Diagnosis and Management
- An algorithm for the early diagnosis and correct approach to dementia management can be built using a multiprofessional team, highlighting all the professionalism that can serve this purpose 5.
- The algorithm can include risk factors, neuropsychological, imaging diagnosis, blood tests, the criteria for differential diagnosis, and possible treatments 5.
- A comprehensive approach to the mental status examination and diagnostic workup of patients suspected of having an emerging neurodegenerative dementia is essential for accurate diagnosis 6.