Dementia + role nutrition 1 Flashcards
Most people with dementia live in..
Asia
Dementia has the highest burden of disease, true/false?
True
Where does AD begin? What is the prevalence?
Hippocampus
60-70%
How long do people with AD live, on average?
- 7-9 years of disease
How does the disease progress (symptoms)?
- Early symptoms: memory complaints
- Later symptoms: disorientation, mood and behaviour changes, confusion, suspicions
- Eventually: basic functions such as speaking, walking and swallowing impaired, ultimately fatal
What are the four main groups of dementia?
AD
Vascular dementia
Dementia with lewy bodies
Frontotemporal dementia
Vascular dementia: prevalence, brain damage, first symptoms?
15-20%
Large/small infarcts (white matter lesions)
Slowness, reduction in executive functions
What type of brain damage happens with AD?
Amyloid plaques, tau tangles, brain shrinkage
Lewy body dementia: prevalence, brain damage, first symptoms?
15%
Lewy bodies of alpha-synuclein
Visual hallucinations, parkinsonism, fluctuating course
Frontotemporal dementia: prevalence, brain damage, first symptoms?
5%
Frontal and temporal lobes damage
▪ Frontal lobes: control behaviour and emotions
▪ Temporal lobes (on either side of the brain): language problems
Behavioural and personality changes, language problems
What % fails the drug trials?
99.6%
Why is finding a treatment so difficult for dementia?
- BBB
- Side effects
- Exact underlying mechanism(s) unclear + heterogeneous
What two symptom-reducing drugs are mainly used?
Cholinesterase inhibitors
NMDA receptor antagonists
What do NMDA receptor antagonists do? In what time frame of disease?
Via glutamate (AD: too much glutamate -> damage to nerves)
Moderate-late AD
What do cholesterase inhibitors do? When are they used in disease?
Prevent breakdown Ach (AD: lower levels)
Mild-moderate AD
What do these drugs that alter disease progression: Aducanumad + lecanemab, do?
▪ No cure, but changes the underlying biology (amyloid-β)
▪ Both monoclonal antibodies
▪ Main difference: mechanism of action
- Aducanumab: removes beta-amyloid
- Lecanemab: blocks formation of amyloid
Aducanumad + lecanemab: why not approved in europe?
Major side effects, limited effects on cognition
▪ More research is needed!
What are non-modifiable risk factors with dementia?
- Age (doubles with every 5 year increase in age): most important risk factor
- Genes
What is the difference between risk factors in early and late onset dementia?
Early:
APP protein
PS1, PS2 proteins
Increased amyloid beta proteins
Rare, 5% of cases
Late:
ApoE gene
ApoE 4: 2 alleles = greatest risk, dose-related
ApoE 2: protective
Amyloid breakdown, transport fat cholesterol
(age the largest risk factor, of course)
What do centenarians without AD have in common?
rare genetic variant in the PLCG2 gene, which has a role in immune system signalling
