Alzheimer Disease
Also written as AD.
Affected brains are typically atrophic, with enlarged ventricles, and show accumulation of tau-containing neurofibrillary tangles in superficial frontal and temporal lobe cortex, which can be similar to Alzheimer disease.
ALZHEIMER DISEASE (AD)
- Most common cause of dementia in older adults
- Rarely symptomatic before age 50
- Prevalence doubles every 5 years from age 60
- Age 60–64 → 1% · Age 85–89 → ≥40%
- Familial = 5–10% · Sporadic = 90–95%
Read this in Neurodegenerative Prion Diseases: CJD, Pathology & Rapid Dementia
What our notes say
- Affected brains are typically atrophic, with enlarged ventricles, and show accumulation of tau-containing neurofibrillary tangles in superficial frontal and temporal lobe cortex, which can be similar to Alzheimer disease. (CNS PATHOLOGY — Past Paper Questions & Answers)
- Local amyloidosis leads to diseases such as Alzheimer's disease (Medical MCQs: Chemical Pathology & Haematology Exam Review)
- Early-onset Alzheimer's disease (chromosome 21 carries the APP gene) (Genetic Disorders Pathology Crash Course: Exam Revision Notes)
- Aβ peptides (same as Alzheimer disease) deposited in walls of meningeal, cortical, and cerebellar vessels (Cerebrovascular Disease: Stroke, Ischemia & Hemorrhage Explained)
- Causes: Progressive neurodegenerative diseases (Alzheimer disease, ALS) — months to years (Neuropathology: CNS Neuronal & Astrocyte Injury Reactions)
- > Aberrant reactivation of synaptic pruning has been implicated in schizophrenia, encephalitis, Alzheimer disease, and frontotemporal dementia (Neuropathology: CNS Neuronal & Astrocyte Injury Reactions)
Study material on Alzheimer Disease
- Neuropathology: CNS Neuronal & Astrocyte Injury Reactions
- CNS Pathology: Neuron & Astrocyte Injury, Reactions & Neurodegeneration
- Psychiatry Year 6 CAT: October 2023, violence, defence mechanisms, hallucinations and sleep, 20 MCQs
Practice questions on Alzheimer Disease
At what age do virtually all Down syndrome patients develop neuropathologic changes characteristic of Alzheimer disease?
- Over age 30
- Over age 40
- Over age 50
- Over age 60
Answer: B. ** Virtually all patients with trisomy 21 older than age 40 develop Alzheimer-like neuropathologic changes. ---
What neurotransmitter is associated with Alzheimer's disease?
- Acetylcholine
- Serotonin
- GABA
- Dopamine
- Glutamate
Answer: A. Alzheimer's disease involves significant loss of acetylcholine-producing neurons, particularly affecting memory and cognitive function. Cholinesterase inhibitors, which increase acetylcholine availability, are used as treatments for Alzheimer's. --- ---
A key structure involved in the formation of new declarative memories, and often affected early in Alzheimer's disease, is the:
- Amygdala
- Thalamus
- Hippocampus
- Basal ganglia
Answer: C. The hippocampus (C) is a critical component of the limbic system, essential for the formation of new declarative memories (facts and events). Its early degeneration is a hallmark of Alzheimer's disease, leading to initial memory deficits. The amygdala (A) is primarily involved in emotion and fear. The thalamus (B) is a relay station for sensory information. The basal ganglia (D) are involved in motor control and proc
What neurotransmitter is associated with Alzheimer's disease?
- Dopamine
- Norepinephrine
- Acetylcholine
- GABA
Answer: C. Degeneration of cholinergic neurons and a reduction in acetylcholine levels are hallmarks of Alzheimer's disease, contributing to cognitive decline, particularly memory impairment.