Alzheimer's disease
Progressive neurodegenerative disease and leading cause of dementia.
Alzheimer's disease (AD) is a neurodegenerative disease and the most common cause of dementia, accounting for around 60–70% of cases. The disease is characterized by progressive cognitive and functional impairment, beginning with difficulty in remembering recent events and ultimately leading to loss of bodily functions and death.
- field
- Neurodegenerative disease
- known_for
- Most common cause of dementia
- first_described_by
- Alois Alzheimer
- global_prevalence_2020
- Approximately 50 million people
- leading_cause_of_death_rank
- Seventh leading cause of death worldwide
Lore & Background
Alzheimer's disease is believed to occur when abnormal amounts of amyloid beta and other misfolded protein deposits, called amyloid plaques and neurofibrillary tangles, accumulate in the cerebral cortex. These aggregates interfere with normal cell function, leading to irreversible degeneration of neurons and loss of synaptic connections. The disease targets the hippocampus, which is associated with memory, likely responsible for early memory impairment. The causes remain poorly understood, but risk factors include an allele of apolipoprotein E, history of head injury, clinical depression, and high blood pressure.
Reader's Guide
Alzheimer's disease has widespread impacts on individuals, families, and society. The median life expectancy following diagnosis of dementia is three to twelve years, and co-occurring movement disorder multiplies risk of death by 1.6. No known treatments can stop or reverse its progression, though some may temporarily improve symptoms. A healthy diet, physical activity, and social engagement may help reduce risk. The financial burden on society is large, with an estimated global annual cost of US$1 trillion.
Did You Know?
- The strongest genetic risk factor is from an allele of apolipoprotein E, a protein involved in the metabolism of fats in mammals.
- Examination of brain tissue is the only way to definitively diagnose Alzheimer's disease.
Frequently Asked Questions
Who is Alzheimer's disease?
Alzheimer's disease is a progressive neurodegenerative condition that attacks the brain and stands as the single most frequent underlying cause of dementia. It was first identified and described by the German psychiatrist Alois Alzheimer.
What are Alzheimer's disease's powers/role?
Its core 'ability' is the gradual erosion of memory, thinking, and daily functioning, beginning with trouble recalling recent events and spreading to broader cognitive and physical capacities over time. This mechanism drives roughly 60–70% of all dementia diagnoses worldwide.
How does Alzheimer's disease's story end?
The condition follows a relentless, one-directional arc in which cognitive and functional decline worsens until the person can no longer perform basic bodily tasks, ultimately resulting in death. No current treatment can reverse that trajectory.
Why is Alzheimer's disease important?
As of 2020, approximately 50 million people globally are living with the condition, making it a massive public-health burden. It also holds the distinction of ranking as the seventh leading cause of death worldwide.
Who first described Alzheimer's disease?
The disease is named after Alois Alzheimer, the psychiatrist who first documented the characteristic brain changes in a patient in the early 1900s. His observations laid the groundwork for modern understanding of the condition.
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