Alzheimer’s disease (AD) is a complex progressive neurodegenerative disease characterized by the accumulation of Aβ plaques and tau NFTs, which are considered to result in neuronal loss and cognitive decline. This slide deck discusses neurobiology and aetiology for AD and highlights topics as risk factors, pathopsysiological hypotheses, and the development and importance of biomarkers.

This slide deck has been developed by Joseph Therriault, PhD, McGill University, Montréal, Québec, Canada; and Professor Serge Gauthier, McGill University, Montréal, Québec, Canada, in collaboration with Cambridge Medical – A Prime Global agency.

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AD-Neurobiology & Aetiology slide1
Neurobiology and aetiology
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Alzheimer’s disease research timeline

Diagnosis of AD has developed from a pathological approach to a more clinical and exclusionary approach.1,3 NIA-AA Criteria published in 2011, combined with a clinical and biological approach developed by the International Working Group (IWG), allowed for the emergence of…

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Alzheimer’s disease is not synonymous with dementia

References on slide:1.Alzheimer's Disease International website. Dementia facts and figures. Available at: Accessed 1 June 2023.

2.Alzheimer's Association website. What is dementia? Available at: Accessed 1 June 2023.


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AD-Neurobiology & Aetiology slide5
What is neurodegeneration?

Aβ and tau pathology in AD results in neuroinflammation, mitochondrial dysfunction, metabolic dysregulation, and protein deficiency.1 The resulting neurotoxicity and disturbed neuroplasticity that occur lead to neurodegeneration.1 In vivo, neurodegeneration in AD is identified through several biomarkers such as fluorodeoxy-glucose…

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Risk factors

AD-Neurobiology & Aetiology slide6
Risk factors
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What factors are at play in Alzheimer’s disease?

While the most prominent risk factor for AD is increasing age, the disease develops as a result of several risk factors that converge.2 Environmental factors such as traumatic brain injury, ischemia, hypoxia, neurotoxins, infections, lifestyle, metabolic parameters, and comorbid cardiovascular…

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Genetic risk factors

The estimated heritability of AD is approximately 70%, and does not differ between sex.1,9 To date, 75 risk loci have been identified for AD and related dementias.8 Several studies in multiple ethnic groups have associated the APOE gene with familial-AD

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Modifiable lifestyle factors and prevention strategies

AD has a long prodromal phase, during which early prevention is important to slow progression of the disease.1 Psychosocial factors such as educational attainment and bilingualism work to enhance cognitive activity, processing, and intellectual capacities.1,3 Regular social engagement has also…

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Accumulation of dementia risk factors over time

Maintaining good physical health in individuals with dementia is important for cognition.1 In early life (i.e., <45 years), lack of education has been associated with an increased risk of dementia.1 In middle life (i.e., 45–65 years), and not necessarily in…

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