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Cracking the Code
Social consequences of manufactured longevity
Riaz Hassan
The signs are that advances in biomedical sciences will add more years
of "manufactured time" to life expectancy in industrialised
countries, resulting in unprecedented rates of survival into older
ages. Increasing longevity will force economic and social changes
and the 20th-century revolution in social roles looks set to continue
into the 21st century.
MJA 2000; 173: 601-603
Life expectancy in rich and poor countries -
Economic effects of longevity -
Longevity and social structure -
References -
Authors' details
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In 1825, a British actuary, Benjamin Gompertz, discovered a
distinctive pattern in human mortality statistics. He found that the
probability of dying was high at birth, and then continued declining
until sexual maturity, after which it increased at an exponential
rate. He and other demographers speculated that the exponential rise
in the risk of death following sexual maturity was the result of a
natural law of mortality.1,2
Ever since, scientists have been looking for evidence of a
"universal" law of mortality that applies to all living things. Now
there is evidence which suggests not only that a law of mortality may
exist, but that the life span of human populations may have already
exceeded the limits implied by such a law -- "a product of the survival
time manufactured by medical technology and lifestyles
modifications".3
For much of human history, life expectancy was around 25 to 30 years.
The mean human life expectancy in industrialised countries has
changed from 25 years in the 18th century to 50 years in 1900, and to
about 75 years now.4 Over two-thirds of the
improvements in longevity in the entire world, from prehistoric
times until the present, has taken place since 1900.5 These changes in
human populations raise a paradox: if evolutionary theories of
senescence are correct and survival into the post-reproductive
period serves no useful purpose, why is the human life span so much
greater than the age when reproduction ceases?3
If, however, senescence is in fact the product of evolutionary
neglect rather than evolutionary intent, then there is good reason to
be optimistic that the process is modifiable, either through direct
manipulation of crucial genes or, more indirectly, by controlling or
manipulating the products of gene expression. Both of these
interventions are a major focus of current biomedical research,
boosted by the Human Genome Project. There may be a price to pay when
only the progression or expression of senescent disease is modified.
Such interventions may simply shift the burden of senescence to other
forms of lethal or debilitating senescent diseases.3
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The distribution of the "manufactured time" being added to human life
expectancy as a result of advances in biomedical sciences is highly
skewed in favour of industrialised countries. In poor countries,
most deaths occur in the young, and result from infectious and
parasitic diseases, wars and starvation.4 In rich countries, most
deaths occur as a result of the diseases of old age, such as cancer,
strokes and heart disease.4,6 The populations of the
rich countries will be the major beneficiaries of the new biomedical
advances. Overpopulation will once again become the concern of the
wealthy countries, rather than just the poor countries with high
fertility rates.4,7,8
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In the first half of the 20th century, when mortality began to fall,
survival rates improved not only at the oldest ages but also in
childhood and during the working years. Under these circumstances
mortality decline is less costly for the State as it does not require
major public welfare transfers. Greater mortality decline in the
early years of life substantially increases the labour force, which
helps to pay the aged pension costs and healthcare of the elderly. In
the second half of the century, mortality decline slowed in the
working ages, and accelerated in older ages. This is the pattern which
now characterises the industrial countries.9 This change (which may be
further boosted by the Human Genome Project) is likely to have major
economic implications for the industrialised countries and will
change their economies drastically over the next three to five
decades.
For example, in Australia, if present trends continue, the
proportion of people aged from 20 to 39 years will increase by only 2%
between 2001 and 2051. In the same period, proportions of populations
aged 60 to 79 years and 80 and over will increase by 122% and 307%,
respectively. By 2051, one in three Australians will be aged 60 and
over. Never before have such proportions been reached in large human
populations.10
The developed countries will have difficulty meeting the costs of
supporting an increasingly larger proportion of elderly. Under
these conditions, according to a World Bank study of the
macroeconomic effects of aging populations, the industrial
economies should see higher aggregate consumption relative to
income and higher real interest rates.11 To avoid a fall in people's
standards of living, economic productivity would need to be
increased, and new tax policies would be needed to aid the process of
capital formation. If the tax rates remain unchanged, government
debt will increase substantially, resulting in higher real interest
rates. Under these conditions, the real gross national product per
capita in most industrialised countries will decline
significantly.11,12
Healthcare costs will be increased by the addition of more years of
life in the older age groups. Some healthcare workers argue that
healthcare for the elderly places an unsustainable economic burden
on national budgets, and one method of control would be rationing
healthcare for older people, and even denying it to those who are 80
years of age or older. These arguments are supported by data from the
United States -- 28% of Medicare bills are paid to only 6% of those
Medicare-eligible, who die within a year.13
An intriguing aspect of healthcare spending in industrialised
countries is that, in general, healthcare costs as a percentage of
gross domestic product (GDP) appear not to be associated with
population aging. Spending on healthcare is highest in the US,
constituting about 14% of its GDP. However, the US has the lowest
percentage of elderly (12.6%) people among the 12 most
industrialised countries. In comparison, Sweden, with 17.8% of the
population older than 65 years, spends 7.5% of its GDP on healthcare.
Furthermore, healthcare spending does not necessarily rise with an
increase in the percentage of elderly persons in the population. In
Japan, the elderly population increased by more than 30% between 1980
and 1990, yet only a 1.6% increase in the proportion of its GDP during
this period went to healthcare. In the US, where the proportion of
those aged 65 and older increased by about 10% in the same period,
healthcare spending went up by 31.5%.4,13
This means that more egalitarian industrialised countries like
Sweden and Japan have not only longer life expectancies compared with
the less egalitarian countries like the United States, but they are
also more likely to be successful in coping with further increases in
life expectancy in the future. The problems of high costs of
healthcare arising from longer life expectancies are likely to be
serious public issues in countries with greater social and economic
inequalities. In this respect Australia is well situated to cope with
the economic and social costs of increasing longevity of its
population.4
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As human life expectancy began to increase in the 20th century, it also
began a revolution in shaping social roles at different stages of
life-cycle. Life course began to become age-graded and
differentiated. One consequence was the reduction in labour force
participation among both the old and the young. The trend has been
towards concentration of education in youth, work in early to middle
adult years, and recreation in the post-retirement years. Human
society became increasingly age-segregated. Although this had had
many beneficial effects, such as expansion of education, greater
economic productivity and innovation, it has also transformed
industrial societies into rigidly age-segregated societies. The
social patterns of modern life are now testing the usefulness of this
structure of life course.14-16
In countries like Australia, growing numbers of elderly people are
rejecting the age constraints on paid work and biases against active
participation of older people in society. Similarly, many young
people are seeking "adult" roles in work, family and entertainment.
These changes are increasing pressures for the development of
age-integrated social structures. Unlike age-segregated
structures, age-integrated structures do not use chronological age
as a criterion for entrance, exit or participation. Sociologists
have proposed an alternative model of life course that would allow
learning, work and leisure to be integrated in the lives of
individuals throughout the entire life course (Box).17
This life-course model is much more suited to the conditions of our
society, which is adding more "manufactured time" to human life,
producing unprecedented longevity. The evidence from Australian
universities' enrolment statistics shows that education is
becoming increasingly age-integrated and is now widely defined as
"life-long". Barriers to work are also being relaxed, as evidenced by
the increasing proportion of high school and university students who
are in paid work. There is growing evidence that repudiates widely
held beliefs about the inevitable and universal intellectual
decline with aging, and ways to prevent the decline that does occur are
being suggested.18,19
The most visible challenge to the age-segregated life course has come
from women. Women have introduced a number of innovations which have
made their life course flexible and age-integrated. Increasing
proportions of women are combining work, education and family. If
this transformation in sex-role attitudes and behaviours
continues, it will affect every facet of modern life. Many
middle-aged women today are performing more roles than men and will
reach old age with greater role flexibility.19
An age-integrated society, with its accompanying cross-age
interaction and flexible life course, will be conducive to promoting
deeper understanding among people and reduce intergenerational
conflict. It may lead to the development of more civil society. New
social values will evolve when people from different age groups get
accustomed to sharing work and family responsibilities, leisure
time and cultural pursuits. These values may produce a greater sense
of connectedness in the community and thus reduce loneliness,
excessive individualism and materialism. Utopia may or may not
result, but, of all the available futures, this appears the most
promising for all ages. Whether we fear it or welcome it, this
manufactured longevity will change our lives and human culture
pervasively.
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human mortality and on a new mode of determining life contingencies.
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Carnes BA, Olshansky SJ, Grahn D. Continuing the search for a law of
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Olshansky SJ, Carnes BA, Grahn D. Confronting the boundaries of
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Fossil M. Reversing human aging: it's time to consider the
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Preston SH. Mortality patterns in national populations.
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Najman JM. The demography of death: Patterns of Australian
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Mason PR. Long-term macroeconomic effects of aging. Finance
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Mason PR, Tryon RW. Macroeconomic effects of projected
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Marwick C. Longevity requires policy revolution. JAMA
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Uhlenberg P. Introduction: why study age integration?
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Kohli MR. Social organization and subjective construction of the
life-course. In: Sorensen AB, Weiner FE, Sherrod LR, editors.
Human Development and the life cycle. Hiilsdale NJ: Erlbaum,
1988.
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Riley MW, Foner A, Riley JW. The aging and society paradigm. In:
Bergtson VL, Schaie KW, editors. Handbook of theories of aging. New
York: Springer, 1999.
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Riley MW, Riley JW Jr. Age integration: conceptual and historical
background. Gerontologist 2000; 40: 266-270.
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Schaie WK, editor. Longitudinal studies of adult psychological
development. New York: Guilford Press, 1983.
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Riley MW, Riley JW Jr. Longevity and social structure: the added
years. Daedalus 1988; 115: 51-74.
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Flinders University, Adelaide, SA.
Riaz Hassan, PhD, FASSA, Professor, Department of
Sociology.
Reprints: Professor R Hassan, Department of Sociology, Flinders
University, GPO Box 2100, Adelaide, SA 5001.
Riaz.HassanATflinders.edu.au
©MJA 2000
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| Social structures |
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| Our current society is age-segregated -- we receive our education when
we are young, we work until we are 60 or so, and then retire and spend our
time in leisure. With increasing longevity, a better social structure would
be age-integrated, in which education, work and leisure are all life-long
activities.
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