Diagnosis and Treatment of Alzheimer Disease

Summary for Physicians

Cognitive Testing and Functional Correlation in Alzheimer Disease

Cognitive impairment is evaluated using a combination of screening tools and comprehensive assessments. Commonly used tests include:

• Mini-Mental State Examination (MMSE): Assesses orientation, memory, language, and attention. Widely used, but less sensitive to early or subtle deficits.

• Montreal Cognitive Assessment (MoCA): More sensitive for detecting mild cognitive impairment, especially executive function and visuospatial deficits.

• Clock Drawing Test & Trail Making Test (A/B): Quick assessments of executive function, attention, and visual-spatial planning.

• Neuropsychological Testing: In-depth evaluation across multiple cognitive domains, particularly useful in ambiguous or early cases.

Clinical Correlation:

• These tools can help stage the disease and track progression.

• Cognitive scores alone do not always fully reflect functional impairment; pairing assessments with instrumental activities of daily living (IADL) scales (e.g., Lawton-Brody) enhances correlation with real-world functioning.

• Disease staging integrates both cognitive performance and impact on daily living.

Role of Amyloid and Tau in MCI and Integration of Disease-Modifying Therapies

Amyloid-beta (Aβ) and tau protein accumulation are core pathological features of Alzheimer’s disease and are now accessible via:

• CSF analysis

• PET imaging (amyloid and tau tracers)

• Blood-based biomarkers (e.g., plasma Aβ42/40 ratios, p-tau), which are emerging as scalable tools for earlier, non-invasive detection.

Disease-Modifying Therapies (DMTs):

• Lecanemab and aducanumab are FDA-approved monoclonal antibodies targeting Aβ plaques, indicated for patients with early symptomatic Alzheimer disease (MCI or mild dementia) and confirmed amyloid pathology.

Practice Integration:

• Requires confirmation of amyloid pathology via biomarker testing.

• Patients undergo MRI screening to assess for ARIA risk (amyloid-related imaging abnormalities).

• Implementation involves interdisciplinary discussion, risk-benefit counseling, regular monitoring (e.g., MRIs during therapy), and coordination with infusion services.

• Access remains a challenge due to cost, payer criteria, and infrastructure needs.

Benefits of Early Diagnosis in Alzheimer Disease

• Timely Access to Therapies: Disease-modifying therapies are only indicated in early stages; delayed diagnosis may preclude eligibility.

• Patient & Family Planning: Enables informed decision-making around finances, care preferences, and safety.

• Care Coordination: Early involvement of care teams, social support, and community resources improves long-term outcomes.

• Clinical Trials: Early identification increases opportunities for trial participation and access to innovative treatments.

• Cognitive Preservation: Early lifestyle and pharmacologic interventions may help slow functional decline.