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Fifth stage
Medicine
Lec-1
.د
منوع
1/1/2014
Geriatric Medicine
Geriatric medicine is concerned particularly with frail older people, in whom physiological
capacity is so reduced that they are incapacitated by even minor illness. They frequently
have multiple comorbidities, and acute illness may present in non-specific ways, such as
confusion falls, or loss of mobility and day-to-day functioning. These patients are prone to
adverse drug reactions, partly because of polypharmacy and partly because of age-related
changes in responses to drugs and their elimination. Disability is common, but patient
function can often improved by the interventions of the multidisciplinary team
Demography
The demography of developed countries has changed rapidly in recent decades.
Life expectancy in the developed world is now prolonged, even in old age. Figure ( 1 ).
Women aged 80 years can expect to live for a further 9 years. However, rates of disability
and chronic illness rise sharply with ageing and have a major impact on health and social
services. In the UK, the reported prevalence of a chronic illness or disability sufficient to
restrict activates is around 25% in those aged 50-64, but 66% in men and 75% in women
aged over 85.
Although the proportion of the population aged over 65 years is greater in developed
countries, two-third of the world population of people aged over 65 live in developing
countries at present, and this is projected to rise to 75% in 2025.
The rate of population ageing is much faster in developing countries Fig.( 2 ) so they have
less time to adjust to its impact.
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BIOLOGY OF AGEING
Ageing can be defined as a progressive accumulation through life of random molecular
defects that build up within tissues and cells. Eventually, despite multiple repair and
maintenance mechanisms, these result in age-related functional impairment of tissues and
organs.
Many genes probably contribute to ageing, with those that determine durability and
maintenance of somatic cell lines particularly important. However, genetic factors only
account for around 25% of variance in human lifespan; nutritional and environmental
factors determine the rest.
PHYSIOLOGICAL CHANGES OF AGEING
The physiological features of normal ageing have been identified by examining disease-free
population of older people, to separate the effects of pathology from those due to time
alone. However, the fraction of older people who age without disease ultimately declines to
very low levels so that use of the term ‘ normal ‘ becomes debatable.
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