Alzheimer's disease
A progressive neurodegenerative disease and the most common cause of dementia.
Among neurodegenerative diseases, Alzheimer's is the leading contributor to dementia, being responsible for an estimated 60–70% of all dementia cases.[1] The cerebral cortex in this disease features an accumulation of misshapen protein deposits, specifically amyloid plaques and neurofibrillary tangles.[2] Worldwide, around 50 million individuals were living with Alzheimer's disease in the year 2020.[3]
Quick Facts
- Field
- Neurology, psychiatry
- Symptoms
- Memory loss
- problems with language
- disorientation
- mood swings
- Complications
- Infections, falls and aspiration pneumonia in the terminal stage
- Onset
- Over 65 years old
- Duration
- Long term
- Causes
- Poorly understood
- Risks
- Genetics
- head injuries
- clinical depression
- hypertension
- psychological stress
- lack of physical and mental exercise
- Diagnosis
- Based on symptoms and cognitive testing after ruling out other possible causes
Facts from the source article.
Key facts and history
Alois Alzheimer, a German psychiatrist and pathologist, provided the initial description of this disease in 1906, and it subsequently received his name.[3] Trouble recalling recent occurrences is the symptom that most frequently appears first.[1] With progression, the condition may bring about difficulties with language, confusion, emotional fluctuations, and behavioral problems.[1] After a dementia diagnosis, the typical survival time ranges from three to twelve years.[4]
An allele of apolipoprotein E, which is a protein that participates in fat metabolism in mammals, constitutes the most significant genetic risk factor.[2] A prior traumatic brain injury, clinical depression, and hypertension are additional elements that raise risk.[2] While some therapies can offer temporary symptom relief, no existing treatments can halt or reverse the disease's advancement.[5] Engaging in a nutritious diet, physical exercise, and social activities may lower the chances of cognitive decline and developing Alzheimer's.[5]
For the 2026 fiscal year, the US National Institutes of Health has allocated US$3.98 billion to its Alzheimer's research program.[6] Dementia-related projects received more than €570 million in awards from the European Union's 2020 Horizon Europe research programme.[6]
What the research sources say
The Alzheimer's disease Fact Sheet from the National Institute on Aging notes that Alzheimer's is currently ranked as the seventh leading cause of death in the United States.[7] The same source states that in 1906, Dr. Alzheimer noticed changes in the brain tissue of a woman who had died of an unusual mental illness.[7] The BBC News article states that tangles of tau appear and the brain cells start producing a molecule called MEG3 that triggers death by necroptosis.[8] The World Health Organization's 2023 fact sheet reports that in 2021, 57 million people were living with dementia worldwide, over 60% of whom live in low-and middle-income countries.[9]
In 2023, researchers from the UK and Belgium reported that they believe they have determined the mechanism by which brain cells die in Alzheimer's disease.[8]
References
- Wikipedia, "Alzheimer's disease" (CC BY-SA 4.0), which cites: "Dementia", www.who.int; "Alzheimer disease", Nature Reviews Disease Primers, May 2021; "Dementia Fact sheet", World Health Organization, 15 March 2023; "Alzheimer's disease", BMJ, February 2009, p. b158 (we also read that source) en.wikipedia.org
- Wikipedia, "Alzheimer's disease" (CC BY-SA 4.0), which cites: "Alzheimer Disease: An Update on Pathobiology and Treatment Strategies", Cell, October 2019, p. 312–339; "Study reveals how APOE4 gene may increase risk for dementia", National Institute on Aging, 16 March 2021; "Alzheimer disease", Nature Reviews Disease Primers, May 2021 (we also read that source) en.wikipedia.org
- Wikipedia, "Alzheimer's disease" (CC BY-SA 4.0), which cites: "Comprehensive Review on Alzheimer's Disease: Causes and Treatment", Molecules, December 2020, p. 5789; "Alzheimer's Disease Fact Sheet", National Institute on Aging; "Early-onset Alzheimer's disease: nonamnestic subtypes and type 2 AD", Archives of Medical Research, November 2012, p. 677–685; "Alzheimer's disease", BMJ, February 2009, p. b158; "Alzheimer's pathogenic mechanisms and underlying sex difference", Cell Mol Life Sci, June 2021, p. 4907–4920; "Comprehensive Review on Alzheimer's Disease: Causes and Treatment", Molecules, en.wikipedia.org
- Wikipedia, "Alzheimer's disease" (CC BY-SA 4.0), which cites: "Survival in dementia and predictors of mortality: a review", International Journal of Geriatric Psychiatry, November 2013, p. 1109–1124; Zheng, "Predictors for survival in patients with Alzheimer's disease: a large comprehensive meta-analysis", Translational Psychiatry, 2024-04-10, p. 184 (original not read by us) en.wikipedia.org
- Wikipedia, "Alzheimer's disease" (CC BY-SA 4.0), which cites: "Dementia Fact sheet", World Health Organization, 15 March 2023; "Alzheimer's Disease Fact Sheet", National Institute on Aging; Demirbas, "Comparison Between Burden of Care Partners of Individuals with Alzheimer's Disease Versus Individuals with Other Chronic Diseases", Neurology and Therapy, August 2023, p. 1051–1068; Demirbas, "Comparison Between Burden of Care Partners of Individuals with Alzheimer's Disease Versus Individuals with Other Chronic Diseases", Neurology and Therapy, August 2023, p. 1051–1068; "Exercise programs for p en.wikipedia.org
- Wikipedia, "Alzheimer's disease" (CC BY-SA 4.0), which cites: "Fiscal Year 2026 NIH Professional Judgment Budget for Alzheimer's Disease and Related Dementias Research: Advancing Progress in Dementia Research", US National Institutes of Health, 5 August 2024; "Horizon Europe research programme", www.alzheimer-europe.org (we also read that source) en.wikipedia.org
- "Alzheimer's Disease Fact Sheet", National Institute on Aging. facts only, no text reused. web.archive.org
- Gallagher, "Scientists discover how brain cells die in Alzheimer's", BBC News, 15 September 2023. facts only, no text reused. bbc.com
- "Dementia Fact sheet", World Health Organization, 15 March 2023. facts only, no text reused. who.int
Each numbered sentence above was checked against the source it cites before publication. Sentences citing Wikipedia adapt text from the English Wikipedia article Alzheimer's disease (contributors), used under CC BY-SA 4.0; this entry is available under the same licence. Other sources were used for facts only; no text or images are copied from them.
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