Alzheimer's Disease

🧠 Standard of Care & Symptoms

Alzheimer's Disease is a progressive, neurodegenerative disorder that primarily affects memory, thinking, and behavior. It is the most common cause of dementia in older adults.

• Key Symptoms: Gradual memory loss (particularly recent conversations or events), difficulty planning or solving problems, confusion with time or place, and changes in mood or personality.
• Pathophysiology: Characterized by the accumulation of extracellular amyloid-beta plaques and intracellular hyperphosphorylated tau neurofibrillary tangles, leading to synaptic loss and brain atrophy.
• Multidisciplinary Care: Management involves neurologists, geriatricians, neuropsychologists, and occupational therapists to optimize independence and cognitive function.

🔍 Biomarkers & Diagnostic Testing

Early and accurate diagnosis is critical, particularly with the advent of disease-modifying therapies that target early stages of the disease.

Modern Diagnostic Tools

• Amyloid & Tau PET Imaging: Positron emission tomography (PET) scans visualize the density and distribution of amyloid plaques and tau tangles in the brain.
• Cerebrospinal Fluid (CSF) Analysis: Lumbar puncture measures levels of amyloid-beta 42, total tau, and phosphorylated tau (p-tau) to confirm pathology.
• Blood Biomarkers: High-precision assays measuring plasma **p-tau217** or **p-tau181** are increasingly used in clinical trials and specialist centers as a non-invasive screening tool.

💊 Prescribed Medications

Pharmacological treatments include symptomatic cognitive enhancers and newly approved disease-modifying therapies.

Symptomatic Therapies

• Cholinesterase Inhibitors: Donepezil (Aricept), Rivastigmine (Exelon), and Galantamine (Razadyne) prevent the breakdown of acetylcholine, supporting neurotransmission in mild-to-moderate stages.
• NMDA Receptor Antagonists: Memantine (Namenda) regulates glutamate activity, protecting neurons from excitotoxicity in moderate-to-severe stages.

Disease-Modifying Biologics

• Lecanemab (Leqembi): A humanized monoclonal IgG1 antibody that binds to amyloid-beta soluble protofibrils. Indicated for patients with Mild Cognitive Impairment (MCI) or mild dementia due to Alzheimer's with confirmed amyloid pathology. Administered via biweekly IV infusions.
• Donanemab (Kisunla): Targets cleared plaque-associated amyloid-beta. Also indicated for early-stage Alzheimer's, showing significant slowing of clinical decline in clinical studies.

📈 Progression & Stages

Alzheimer's Disease symptoms progress gradually over several years, typically divided into three broad clinical stages:

• Early Stage (Mild): The person can function independently, drive, work, and socialize. However, they may experience minor memory lapses, such as forgetting familiar words, misplacing valuable objects, or struggling with planning and organization.
• Middle Stage (Moderate): Typically the longest stage, where damage to brain cells makes it difficult to perform daily tasks or express thoughts. Symptoms include confusion about location or date, increased risk of wandering, personality/behavioral changes, and difficulty choosing site-appropriate clothing.
• Late Stage (Severe): In this final stage, individuals lose the ability to respond to their environment, carry on conversations, and, eventually, control physical movements. High-level care is required to assist with personal hygiene, swallowing, and round-the-clock mobility.

🔬 Active Clinical Trials

Active clinical trials are investigating therapies targeting tau protein aggregation, neuroinflammation, metabolic dysfunction, and gene therapy.

🗺️ Next Steps After Diagnosis

If you or a loved one has recently been diagnosed with early-stage Alzheimer's, take these active steps:

1. Establish a Baseline: Get a comprehensive cognitive and functional assessment to plan for future support needs.
2. Confirm Amyloid Status: Discuss with a neurologist if you are a candidate for amyloid-targeting therapies (which require amyloid PET or CSF confirmation).
3. Optimize Heart Health: Management of cardiovascular risk factors (hypertension, diabetes, cholesterol) is strongly linked to slower cognitive decline.
4. Organize Care & Safety: Secure legal, financial, and safety plans (e.g. driving evaluations, home safety adjustments) while cognitive function is high.

❓ Patient FAQ

Q: What is the difference between Alzheimer's and Dementia?
A: Dementia is an umbrella term for a decline in mental ability severe enough to interfere with daily life. Alzheimer's is a specific disease under that umbrella, accounting for 60-80% of dementia cases.

Q: Are amyloid-targeting drugs a cure?
A: No. Lecanemab and Donanemab do not reverse or cure Alzheimer's. They slow down the rate of cognitive decline by clearing amyloid plaques, helping patients maintain independence for longer.

Q: Is Alzheimer's Disease genetic?
A: The APOE e4 gene is the strongest genetic risk factor for late-onset Alzheimer's. Having one or two copies increases risk but does not guarantee development of the disease. Rare early-onset forms are directly caused by mutations in the APP, PSEN1, or PSEN2 genes.