AGE Flashcards
Give 3 reasons for the “squaring of the rectangle” ie. death almost exclusively in old age now vs. premature death
- less infant mortality
- better standard of living
- improved public health/sanitation
- improved diet
- modern medicine
Suggest why there is higher disability prevalence in old age.
- physiological ageing bring illness threshold closer
- acute illness has larger impact
- isolation/poverty
- increased burden of chronic illness
What does Frie’s Compression of Morbidity state for the years we add on to life expectancy…
-The years we add on to life expectancy…
…the period of suffering gets shorter
What is frailty?..the result of which leads to increased vulnerability to adverse outcomes
A physiological syndrome characterised by decreased reserve and resistance to stressors due to cumulative decline
Strehler’s concepts for a true ageing process vs. disease are universal, intrinsic, progressive and deleterious, explain each.
Universal: in all members of species
Intrinsic: changes of endogenous skin
Progressive: change continues with time
Deleterious: eventually harmful
The fact that the older age reached without disabiility = shorter period of dependency before death, should mean what clinically should we strive to do?
- postpone age of onset of disability as much as poss
- as this will prevent suffering
A healthy old age is possible. How should we manage disease vs death?
- postpone disease onset as much as poss
- do not postpone death in this way
Explain the Mutation Accumulation Theory of ageing (non-adaptive evolution)? “miscellaneous collection of late acting deleterious genes that accumulate over millenia…->ageing”
- powers of natural selection decline as we age
- early expressed genes effect most of population
- those expressed after repro are lost from evolutionary control
Explain the Antagonistic Pleiotropic Genes Theory of ageing (non-adaptive evolution)?
- gene has an early good effect so is retained
- but has a bad late effect that contributes to ageing
What is the “Disposable Soma” Theory of Ageing (builds on non-adaptive evolution)? Includes species specific longevity due to varying ecological niche/priorities
- organism as machine that takes free energy and makes progeny
- success is to ensure survival of genes in most efficient way
How can the 2nd law of Thermodynamics be applied to ageing?
-entropy increases, we should age and decay over time
What does the “Neuroendocrine Theory” say about HOW we age?
- functional decrease in neurones &hormones -> ageing
- HPA controls growth maybe controls ageing too
What does “cross link formation” mean as a cellular explanation of how we age?
-collagen cross-link formation alters the physical and chemical properties of cells
HSP are produced at times of cell stress, how are they implicated in how we age?
- they disassemble proteins and transport in new ones
- we have less HSP as we age
- we have a decreased ability to cope with stressors ->ageing
What was Haflick’s phenomena? Discovered by looking at fibroblasts grown in culture..aim to explain how we age..?
- showed the fibroblasts undergo a set no. of divisions then stop
- younger sources do more divisions
What are Geronto-Genes and Assurance-Genes in relation to ageing?
-Geronto-Genes: age quicker
-Assurance-Genes: slow ageing
Genetics play large role in life expectancy
