Alzheimer's disease
Also called: Dementia, Alzheimer disease
The most common cause of dementia: a progressive brain disease that gradually destroys memory, thinking and eventually the ability to carry out daily activities.
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About 55 million people live with dementia; Alzheimer's causes 60–70%.
What happens in the body
Amyloid-beta plaques and tau tangles accumulate, synapses and neurons are lost, starting in the hippocampus and spreading through the cortex.
Causes
- Amyloid and tau pathology; rare inherited forms (APP, PSEN1, PSEN2)
Risk factors
- Age
- APOE ε4 gene
- Family history
- Hypertension, diabetes, obesity in mid-life
- Smoking
- Hearing loss
- Physical and social inactivity
- Head injury
- Low education
Symptoms
- Forgetting recent events and conversations
- Repeating questions
- Getting lost
- Word-finding problems
- Difficulty planning and handling money
- Mood and personality changes
- Later: dependence for all care
Diagnosis — tests and examinations
- Cognitive testing
- Blood tests to exclude reversible causes (B12, thyroid)
- MRI brain
- Amyloid PET, CSF or blood biomarkers in specialist settings
Treatment
Medicines and medical treatment
- Cholinesterase inhibitors (donepezil, rivastigmine, galantamine)
- Memantine for moderate–severe disease
- Anti-amyloid antibodies (lecanemab, donanemab) for early disease in eligible patients where approved
Self-care, home remedies and lifestyle
- Stay physically, mentally and socially active
- Routines, memory aids, safety adaptations at home
- Carer support and advance care planning
Possible complications
- Loss of independence
- Falls
- Infections
- Swallowing problems
Prevention
- Treat hearing loss, blood pressure and diabetes
- Exercise, not smoking, social engagement, education
Outlook
Progressive; average survival 8–10 years after diagnosis.
When to see a doctor
See a doctor for memory problems that affect daily life.
Sources and further reading
These sources cover this condition. They have not been checked against every statement on this page.
Related conditions
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