Ageing of the Central Nervous System Flashcards
Define ageing
the gradual changes in the structure and function that occur with time, that do not result from disease or gross accidents, and that lead to the increased probably of death as the person grows older
Give examples of some neurological disorders associated with ageing
stroke alzheimers dementias parkinsons motor neurone disease
What is lost in the brain as we age?
Which area is most affected?
Which area stays relatively stable?
- neuronal volume loss
- prefrontal cortex most affected
- primary visual cortex stays relatively stable
How do cells change with ageing?
- neuronal cell numbers stay stable but volume decreases
- oligodendrocytes increase?
- astrocytes stable
- microglia increase - inflammatory phenotype, senescent but primed (ready to produce inflammatory repsonse)
How do the following change with ageing and what conditions result?
- dopamine
- serotonin
- acetylcholine
- GABA
dopamine = decreases --> parkinsons serotonin = and BDNF are stable ACh = reduced transferase, reduced M1 M2 receptor role in alzheimer GABA = reduced receptor and GAD, huntingtons
What are vascular changes and white matter lesions?
- reduced blood flow, reactivity and density
- mainly frontal (anterior circulation)
- white matter lesions - increase with age, many have them but no effect
How are levels of dementia changing?
- incidence increasing
- only because of ageing population
- incidence is actually decreasing as better prevention
What are the three stages of cognitive decline?
- preclinical
- mild cognitive impairment
- dementia
What are the features of preclinical cognitive decline?
- silent phase, brains changes without measurable symptoms
- individual may notice changes, but not detectable on tests
- a stage where the person knows but the doctor doesn’t
What are the features of mild cognitive impairment?
- cognitive changes are of concern to individual and/or family
- one or more cognitive domains impaired signiticantly
- preserved AODLs
What are the features of dementia?
- cognitive impairment severe enough to interfere with everyday abilities
What are the challenges with the ‘confused older patient’?
- live alone
- lack of information
- cognitive impairment
- complex comorbidities
- often misdiagnosed
- serious constrains on proper evaluation and assessment
- requires teamwork
Which conditions are classed as intellectual failures?
- What is their broad presentation?
- What are the interventions ?
Which? = dementia, MCI, delerium Presentation = forgetful, not usual see, acuteness of symptoms is key, effect on everyday function Interventions = diagnosis, drugs, support
What are the features of dementia?
What are the causes
What are the interventions?
Features = chronic syndrome, global impairment (not just memory), affects everyday function Causes = alzheimers, vascular disease, LB dementia, fronto-temporal dementia, posterior cortical atrophy Interventions = diagnosis, drugs, support
What is the pathology of Alzheimer’s disease?
- amyloid cascade
- dysregulation of protein handling
- amyloid precursor in cell membrane, secretases maintain it
- not efficient
- amyloid subunits floating around
- clump to form amyloid plaques
- neuroinflammation
- neuronal damage
- most atrophy in temporal lobe and hippocampus also neurofibrillary tangles TAL microtubule regulation intracellualr
What are the risk factors for Alzheimer’s?
- age, female
- smoking, obesity, diabetes
- head injury
- homcysteine
What are the protective factors for alzheimer’s?
- education (IQ, socioeconomic)
- exercise
- wine, coffee, tumeric
- brain training?
- living with others, bilingualism
What is delerium?
- acute neuropsychiatric condition
- affects attention, alertness, cognition
- most common post surgical complication
What are the symptoms of Parkinson’s?
tremor
bradykinesia
hypertonia
What is the pathology behind parkinsons?
- degeneration of dopaminergic nigrostriatal neurones
- loss of pigmented cells in the pars compacts of the substantia nigra
- decerase striatal dopamine
- lewy bodies
