Now, keep up to date
with daily feeds of newly posted stories
about America's Seniors...click on the box
to the left
Study finds the effects of
population aging have been exaggerated
Laxenburg, Austria, September 2010 – 9th
September 2010-- Due to increasing life-spans
and improved health many populations are
'aging' more slowly than conventional
measures indicate.
In a new study, to be published in Science,
(10 September) scientists from the
International Institute for Applied Systems
Analysis (IIASA) in Austria, Stony Brook
University, US, (SBU), and the Vienna
Institute of Demography (VID) have developed
new measures of aging that take changes in
disability status and longevity into
account.
The results give policymakers faced with
growing numbers of elderly new tools to more
accurately determine the cost of an aging
population and to determine more appropriate
retirement ages.
Currently, assessments are frequently based
on United Nations aging forecasts that
include the proportion of the population
that is 65 years and older, and the "old age
dependency ratio" (OADR), which considers
the number of people dependent on others
when they reach age 65.
"Those measures are based on fixed
chronological ages, and this can generate
misleading results," says Dr Warren
Sanderson, from IIASA and SBU.
"When using indicators that assume fixed
chronological ages, it's assumed that there
will be no progress in factors such as
remaining life expectancies and in
disability rates. But many age-specific
characteristics have not remained fixed and
are not expected to remain constant in the
future."
However, many people over 65 are not in need
of the care of others, and, on the contrary,
may be caregivers themselves.
The authors provide a new dependency measure
based on disabilities that reflect the
relationship between those who need care and
those who are capable of providing care, it
is called the adult disability dependency
ratio (ADDR).
The paper shows that when aging is measured
based on the ratio of those who need care to
those who can give care, the speed of aging
is reduced by four-fifths compared to the
conventional old-age dependency ratio.
Co-author Dr Sergei Scherbov, from IIASA and
the VID, states that "if we apply new
measures of aging that take into account
increasing life-spans and declining
disability rates, then many populations are
aging slower compared to what is predicted
using conventional measures based purely on
chronological age."
The new work looks at "disability-free life
expectancies," which describe how many years
of life are spent in good health. It also
explores the traditional measure of old age
dependency, and another measure that looks
specifically at the ratio of disabilities in
adults over the age of 20 in a population.
Their calculations show that in the United
Kingdom, for example, while the old age
dependency ratio is increasing, the
disability ratio is remaining constant. What
that means, according to the authors, is
that, "although the British population is
getting older, it is also likely to be
getting healthier, and these two effects
offset one another."
New measures of aging that include not just
changes in longevity, but accurate numbers
about disability rates, "can help educate
the public about the likely consequences of
improvements in health and longevity," the
authors say.
And such measures have policy implications
because, "slow and predictable changes in
pension [retirement] age justified by an
increased number of years of healthy life at
older ages, may be more politically
acceptable than large, abrupt changes
justified on the basis of budget
stringency."
