The demographic components of population aging in China

Past trends in fertility and mortality in China have led to an age composition that will age rapidly in the coming decades. In this paper we examine measures of population aging in China from 1953 to 1982, and then project population aging to the year 2050 using a cohort-components methodology. The projected measures of population aging that result from these forecasts are then decomposed into the relative contributions that are made to these changes by past, present, and future trends in fertility and mortality. Results indicate that China's population will age at an unprecedented rate over the next 70 years, both in terms of the absolute size of the elderly population and their proportion of the total population. At least 50 percent of the projected increase in population aging in China between 1980 and 2050 will be a product of the momentum for aging that is already built into the present age structure and vital rates. However, prospective trends in the measures of population aging become increasingly more sensitive to varying assumptions about fertility and mortality with time, and as older age groups are considered. This analysis provides the demographic basis for evaluating the possible effects of population aging on health care, social security, and other social and economic issues.     

Selective survival, aging and society

The concept of selective survival to advanced ages is introduced and discussed in relation to the black/white mortality "crossover" in the United States. Crossover refers to the phenomenon wherein black mortality rates become lower than white mortality rates after approximately age 75. This reversal of mortality rates between advantaged and disadvantaged populations also occurs between Native Americans and whites. Such crossovers have significant implications for explaining differences in patterns of aging across populations. We argue that higher rates of selective survival in disadvantaged, high mortality populations result in a greater proportion of healthy, very old people who may require less nursing-home care, who have low suicide rates, and who enjoy higher status in the family and community. Differences between populations with regard to selective survival imply that chronological age alone is not always a useful measure of aging and old age. Finally, we identify further lines of inquiry about selective survival and its effects on aging.     

Experimental evolution of aging, growth, and reproduction in fruitflies

We report in this paper an evolutionary experiment on Drosophila that tested life-history theory and the evolutionary theory of aging. As theory predicts, higher extrinsic mortality rates did lead to the evolution of higher intrinsic mortality rates, to shorter lifespans, and to decreased age and size at eclosion; peak fecundity also shifted earlier in life. These results confirm the key role of extrinsic mortality rates in the evolution of growth, maturation, reproduction, and aging, and they do so with a selection regime that maintained selection on fertility throughout life while holding population densities constant.     

Die neue alternde Gesellschaft

In China, fundamental changes in population development have occurred during the past 50 years. The demographic transition in China required only a few years, while in most European countries this process took several decades. The fertility and mortality rates have declined very quickly, like in Japan and South Korea. China is one of the countries that has passed through the transition process the quickest. In the following article, this development is considered in more detail. Even if the fertility and mortality rates should stabilize at a new low level, which today certainly cannot be conclusively stated, the age effects will persist for the next few decades. The demographic aging during recent years will increase enormously in the coming decades. This development leads to far-reaching social and political challenges. The demographic aging in China is associated with a loss of function of the family. Both developments have a strong impact on the old-age insurance and on old-age care. Only a few years ago did politics and society start to respond with comprehensive reforms. For example, a modern pension system was introduced, but only in urban areas of China. Rural populations are still waiting for such reforms even today. Currently, there is a pilot project to gain experience with a pension system for the entire population. In contrast to the old-age insurance, in China there is very little public interest in old-age care because the elderly have until now been only a matter for the family. In the near future, the changing role of family and demographic aging will require a greater discussion about the care of older people in China.     

Paths for future population aging

Developed countries with low fertility and mortality rates are already experiencing population aging and will continue to do so. Some developing countries undergoing demographic transitions are beginning to acknowledge the issues of population aging. The projected declines in fertility in other developing countries will mean substantial population aging in the future. Alternative measures for population aging can clarify issues that arise with this process. Because population aging is inevitable, all countries need to incorporate aging policies with population policies.     

Age-related trends in mortality from COPD in Lithuania, 1989 to 1998

OBJECTIVE: To assess the age-related trends in mortality from COPD in middle-aged and elderly populations of Lithuania during a 10-year period (1989 to 1998). METHODS: Annual mortality was reported as the age-standardized mortality rates. Mortality rates were standardized to the 1989 European population. Trends in mortality were assessed by logarithmic regression coefficient beta that, expressed by percentage, estimated the average annual change in mortality. RESULTS: Analysis of mortality from COPD in the Lithuanian population during this 10 years revealed that mortality rates directly related to older age, and the indexes of men in various age groups were twofold to threefold greater than those of women. Annual change in mortality assessed by logarithmic regression coefficient in men aged 35 to 64 years was - 5.7% (p = 0.002) and in age group >or= 65 years it was - 2.9% (p = 0.001); in women, the change in mortality was - 7.2% (p = 0.006) and - 2.5% (p = 0.03), respectively. CONCLUSION: Mortality from COPD in Lithuania during the 10-year period was decreasing in middle-aged and elderly populations and in both men and women. Decrease in mortality occurred at a slower rate in the elderly population than in middle-aged population.     

Could accelerated aging explain the excess mortality in patients with seropositive rheumatoid arthritis?

Objective

To determine whether the mortality pattern in patients with seropositive rheumatoid arthritis (RA) is consistent with the concept of accelerated aging, by comparing the observed mortality rates in patients with RA with the age‐accelerated mortality rates from the general population.

Methods

A population‐based inception cohort of patients with seropositive RA (according to the American College of Rheumatology 1987 criteria) was assembled and followed up for vital status until July 1, 2008. The expected mortality rate was obtained by applying the death rates from the general population to the age, sex, and calendar year distribution of the RA population. The observed mortality was estimated using Kaplan‐Meier methods. Acceleration factors for the expected mortality were estimated in accelerated failure time models.

Results

A total of 755 patients with seropositive RA (mean age 55.6 years, 69% women) were followed up for a mean of 12.5 years, during which 315 patients died. The expected median survival was age 82.4 years, whereas the median survival of the RA patients was age 76.7 years. Results of statistical modeling suggested that, in terms of mortality rates, patients with RA were effectively 2 years older than actual age at RA incidence, and thereafter the patients underwent 11.4 effective years of aging for each 10 years of calendar time.

Conclusion

The overall observed mortality experience of patients with seropositive RA is consistent with the hypothesis of accelerated aging. The causes of accelerated aging in RA deserve further investigation.

     

The high incidence of esophageal cancer in parts of China may result primarily from genetic rather than environmental factors

About 40 000 inhabitants migrated from a high‐risk area of esophageal squamous cell carcinoma (ESCC) to a low‐risk area of esophageal cancer 40 years ago. Little is known about the change in the mortality in esophageal cancer among these immigrants. This study examined the impact of changing environments on esophageal cancer by comparing age‐standardized mortality rates of immigrant group to the rates of native population (natives who live in high cancer location and have never moved) and host populations (hosts who live in low cancer location and have never moved people). All ESCC deaths taking place during 1999–2004 among the migrant, native, and host populations were identified by retrospective population‐based screening. Direct age‐adjusted mortality rates were calculated by using the China population of year 2000 as standard population. From 1999–2004, the average annual age‐adjusted mortality of ESCC for the migrant, native, and host population was 61.6/100 000, 59.7/100 000, and 6.7/100 000, respectively. No decreasing tendency was found in mortality rate of ESCC in the population of young immigrants. The mortality rate of ESCC of migrants remained high even they had been living in the low endemic region for 40 years. This study strongly suggested that genetic susceptibility, rather than environment exposure, is responsible for the high risk of ESCC in the migrants.     

The aging baboon: comparative demography in a non-human primate

Why do closely related primate genera vary in longevity, and what does this teach us about human aging? Life tables of female baboons (Papio hamadryas) in two wild populations of East Africa and in a large captive population in San Antonio, Texas, provide striking similarities and contrasts to human mortality patterns. For captive baboons at the Southwest Foundation for Biomedical Research, we estimate the doubling time of adult mortality rate as 4.8 years. Wild females in free-living populations in Tanzania and in Kenya showed doubling times of 3.5 and 3.8 years, respectively. Although these values are considerably faster than the estimates of 7-8 years for humans, these primates share a demographic feature of human aging: within each taxon populations primarily vary in the level of Gompertz mortality intercept (frailty) and vary little in the demographic rate of aging. Environmental and genetic factors within taxa appear to affect the level of frailty underlying senescence. In contrast, primate taxa are differentiated by rates of demographic aging, even if they cannot be characterized by species-specific lifespan.     

Families and intergenerational relationships in aging societies: comparing the United States with German-speaking countries

Summary Industrialized nations have experienced many demographic changes favoring older adults during the last few decades of the 20^th century. This article is a comparative examination of current and future trends in intergenerational relationships and aging in two societies: the United States and German-speaking countries. While comparing similarities and significant differences between the cultures, we examine five issues related to these trends for families and intergenerational relationships in the 21^st century: (1) consequences of population aging for family structures and relationships – the emergence of the beanpole family structure and the longer years of linked lives across generations; (2) the debate about the decline of the family; (3) intergenerational solidarity over the life course; (4) intergenerational conflict across the life course; (5) prospects for solidarity and conflict between generations in the 21^st century. Similarities between cultures include the demographic realities of population aging, the shift from pyramids to beanpoles, more years of shared lives between and across generations, more non-traditional family forms, and intergenerational conflicts in families. Differences include diverse replacement fertility rates, alternative approaches to governmental supports for families and aging members, and possible differences in cultural values regarding individualism. Received: 8 January 2000 Accepted: 26 September 2000     

The Danish National Diabetes Register: trends in incidence,prevalence and mortality

Aims/hypothesis  The aim of the study was to describe trends in the incidence rate, prevalence and mortality rate for diabetes in Denmark. Methods  Healthcare registers at the National Board of Health were used to compile a register of diabetic patients in the Danish population (5.4 million people). Age- and sex-specific prevalence, incidence rates, mortality rates and standardised mortality ratios relative to the non-diabetic part of the population were calculated. Results  The register contains records for about 360,000 persons with diabetes; 230,000 were alive at 1 January 2007, corresponding to an overall prevalence of 4.2%. The prevalence increased by 6% per year. In 2004 the incidence rates were 1.8 per 100,000 at age 40 years and 10.0 per 100,000 at age 70 years. The incidence rate increased 5% per year before 2004 and then stabilised. The mortality rate in the diabetic population decreased 4% per year, compared with 2% per year in the non-diabetic part of the population. The mortality rate decreased 40% during the first 3 years after inclusion in the register. The standardised mortality ratio decreased with age, from 4.0 at age 50 years to 2.5 at age 70 years and just under 2 at age 85 years, identically for men and women. The standardised mortality ratio decreased 1% per calendar year. The lifetime risk of diabetes was 30%. Conclusions/interpretation  The prevalence of diabetes in Denmark rose in 1995–2006, but the mortality rate in diabetic patients decreased faster than that of the non-diabetic population. The mortality rate decreased markedly just after inclusion in the register. Incidence rates have shown a tendency to decrease during the last few years, but this finding should be viewed with caution.     

Long-term trends of the demographic aging in Germany

At the beginning of the 21st century, Germany is experiencing the highest demographic aging after Japan. The aging process was first initiated by the increase of life expectancy, especially at the age above 60 years which caused an increase in the number of old people. During the next phase (1970-2000) the aging process was additionally affected by decreasing birth rates. Since the end of the 1960s the total fertility rate in Germany has been below the replacement level. As a consequence the number of children is decreasing and the number of old people has been increasing for 30 years. Various population projections published by the Institute for Population Research and Social Policy (IBS) demonstrate that the aging process will intensify during the next 50 years: the number of the oldest old population will triple, and the dependancy ratio will at least double. This process cannot be stopped or considerably diminished by an increasing number of young immigrants. After 2050 the cohorts born after the second world war (the baby boom cohorts) will be dead. But the decreasing number of old people beyond 2050 will not automatically lead to a lower dependancy ratio, because the age group 0-20 is diminishing continuously. Only a rise of the total fertility rate to the replacement level of 2.1 children per women could stop the aging process effectively in the long run (i.e., after two generations or after 60 years, respectively). In this case, the dependancy ratio will not double or triple but increase by a factor of 1.5.     

Age-related patterns of fertility in captive populations of birds and mammals

We have analyzed birth records from the International Species Inventory System database of zoo animals to describe patterns of fertility as a function of age in birds and mammals. Unlike age at death, fertility in captive populations is partly controlled by animal keepers depending on availability of space and potential mates and on the aims of captive propagation programs. Thus, fertility records must be considered carefully to avoid potential age-specific biases. The zoo data suggest that fertility declines from a peak at young adult ages in most species. The rate of decline in reproductive function is correlated with the rate of somatic aging, indicated by the increase in mortality rate with age, and with the age at peak fertility. Over the sample as a whole, these patterns do not differ systematically between the sexes, nor do they differ between birds and mammals. While it is clear that the demographic consequences of aging of the reproductive system follow a different course than the aging of somatic tissue, the rates of each are correlated either through functional connections or through parallel evolutionary responses to common selective factors.     

Rapidly changing myeloma epidemiology in the general population: Increased incidence,older patients,and longer survival

The incidence of multiple myeloma is characterized by a steep increase with advancing age. Dramatic improvements in survival have been reported in clinical trials; however, elderly patients are generally underrepresented in these. The aims of this study are to review patterns of incidence and survival in multiple myeloma in the general population. We searched PubMed for population‐based studies on trends in incidence and survival published between January 1, 2000 and June 30, 2017 and based on regional or national cancer registries and report the following results of the review. The age‐adjusted incidence of multiple myeloma has increased during the second half of the twentieth century in some countries but remained stable in areas with high case ascertainment and access to universal medical care. The crude incidence is increasing globally due to an aging population. Survival rates have improved, and 5‐year relative survival rates are now around 50% and over 60% in patients 65‐70 years or younger. Preliminary data suggest a 3‐fold increase in the prevalence of multiple myeloma. We conclude that the number of multiple myeloma patients is increasing in the general population due to (i) aging populations and (ii) more patients living longer due to modern drugs.     

Mortality trends in Abidjan, C?te d'Ivoire, 1983-1988.

To assess changes in mortality in Abidjan since the development of the AIDS epidemic, we compared official city mortality statistics and hospital fatality rates in 1983, before AIDS was recognized in Abidjan, with those in 1988. Review of records in the city's major hospitals showed that fatality rates (deaths per 1000 admissions) in adult medical patients increased by 54% between 1983 and 1988, with increases of 106 and 98% in men 20-29 and 30-39 years of age, respectively, and 199 and 42% in women of the same age ranges. Mortality rates in surgical patients showed little change, while in children they declined. Over the same period, official mortality statistics for the city showed reduced mortality rates in children and women 20-29 years of age, but an increase in mortality rates of 54% in men 20 years of age and older, and of 28% in women aged 30 years and older. HIV infection may be a major cause of the increased adult mortality documented in hospital and city records, and jeopardizes improved survival from preventive measures such as maternal and child health services.     

Simultaneous/multiple cause-delay (SIMCAD): an epidemiological approach to projecting mortality

Methods being used to project mortality are based on the hypothetical elimination of one or more diseases from the population or on extrapolation from observed mortality rates. This research presents an alternative projection method based on an epidemiological theory of aging and mortality change that is consistent with recent mortality transitions. The model is founded on the observation that recent mortality declines in the United States are attributable to improved life styles and advances in the prevention and treatment of degenerative diseases and that the risk of dying from such diseases is being redistributed (or delayed) from younger to older ages. A test using U.S. mortality and population data indicates that this alternative method is promising--particularly for projecting mortality rates from major chronic degenerative diseases among populations in middle and older ages.     

Evolutionary patterns among measures of aging

Maximum lifespan has been one of the most common aging measures in comparative studies, while the Gompertz model has recently attracted both proponents and critics of its capacity to adequately describe the acceleration of mortality in the oldest age classes. The Gompertz demographic model describes age-dependent mortality rate acceleration and age-independent mortality using the parameters α and A, respectively. Evolutionary biologists have predominantly used average longevity in studies of aging. Little is known about the evolutionary relationships of these measures on the microevolutionary time scale. We have simultaneously compared Gompertz parameters, average longevity, and maximum longevity in 50 related populations of Drosophila melanogaster, many of which have been selected for postponed aging. Overall, these populations have differentiated significantly for the A and α parameter of the Gompertz equation, as well as average and maximum longevity. These indices of aging appear to measure the same genetic changes in aging. However, in some specific population comparisons, the relationships among these measures are more complex. In a second experiment, environmental manipulation of longevity had substantially different effects from genetic differentiation, with the A parameter accounting for changes in overall mortality. The adequacy of the maximum lifespan and the Gompertz equation as indices of aging in evolutionary studies is discussed.     

Probabilistic population projections with migration uncertainty

We produce probabilistic projections of population for all countries based on probabilistic projections of fertility, mortality, and migration. We compare our projections to those from the United Nations’ Probabilistic Population Projections, which uses similar methods for fertility and mortality but deterministic migration projections. We find that uncertainty in migration projection is a substantial contributor to uncertainty in population projections for many countries. Prediction intervals for the populations of Northern America and Europe are over 70% wider, whereas prediction intervals for the populations of Africa, Asia, and the world as a whole are nearly unchanged. Out-of-sample validation shows that the model is reasonably well calibrated.In this paper we describe a method for probabilistic projection of population for all countries, with a focus on accounting for uncertainty in projections of international migration. In particular, we are motivated by the needs of the United Nations (UN) Population Division in producing population projections for all countries until 2100 based on projections of fertility, mortality, and migration.A variety of forces contribute to the ebb and flow of international migration. Economic theories at varying levels of granularity indicate that migration flows can arise from individual attempts to maximize income (1, 2), household-level mitigation of risk (3, 4), or differences in global supply and demand for labor (5, 6). Individuals decide to migrate based on an assessment of push and pull factors (7), which may include migration policy (8), geopolitical conflict (9), and quality of the natural environment (10, 11). Networks of migrants provide a feedback mechanism such that migration flows tend to perpetuate themselves over time (12, 13). Bijak (14) gives a thorough overview of theories and models of international migration. Despite their acknowledged role in driving migration, our model does not make use of push and pull factors, economic or otherwise, as covariates. Such factors are largely too difficult to predict in the long term to be of use. Instead, we appeal to the inertia of self-perpetuating migration patterns by modeling migration as an autoregressive process.Historically, most methods for projecting population have been deterministic. If the current population is known, broken down by age and sex, and future age- and sex-specific rates are projected for fertility, mortality, and migration, then the cohort-component method produces population projections (15). However, the UN Population Division now produces probabilistic projections of population, fertility, and mortality for all countries, but these projections still condition on deterministic migration projections (16, 17). The current methodology in the UN’s World Population Prospects (WPP) differs from country to country but typically projects that net migration counts will remain constant until 2050 and drop deterministically to zero by 2150 (17). A deterministic gravity model that assumes migration is proportional to population size raised to some power (18, 19) is more flexible than the simpler WPP migration projections but still lacks quantification of uncertainty. Probabilistic population projection models that account for migration uncertainty have been developed for a small number of countries, typically only those with good data (20). Our method produces projections for all countries.In many countries, migration is a substantial driver of population change. By failing to account for uncertainty about future migration, the current projection methodology understates the uncertainty in population projections.We have developed a probabilistic methodology for projecting net migration for all countries (21). Based on this, we have developed a method for projecting populations for all countries by age and sex that takes account of uncertainty about migration. The method ensures that migration balances across the globe in all sex and age groups and that the large labor migration flows to and from the countries of the Arabian Peninsula are projected appropriately so that projected migration to the Gulf States does not substantially drive down projected migration in all other countries.     

2014 Global geographic analysis of mortality from ischaemic heart disease by country,age and income: Statistics from World Health Organisation and United Nations

Background

Ischaemic heart disease (IHD) is the leading cause of death worldwide and its prevention is a public health priority.

Method

We analysed worldwide IHD mortality data from the World Health Organisation as of February 2014 by country, age and income. Age-standardised mortality rates by country were calculated. We constructed a cartogram which is an algorithmically transformed world map that conveys numbers of deaths in the form of spatial area.

Results

Of the countries that provided mortality data, Russia, the United States of America and Ukraine contributed the largest numbers of deaths. India and China were estimated to have even larger numbers of deaths. Death rates from IHD increase rapidly with age. Crude mortality rates appear to be stable whilst age-standardised mortality rates are falling. Over half of the world's countries (113/216) have provided IHD mortality data for 2008 or later. Of these, 13 countries provided data in 2012. No countries have yet provided 2013 data. Of the 103 remaining countries, 24 provided data in 2007 or earlier, and 79 have never provided data in the ICD9 or ICD10 format.

Conclusions

In the countries for which there are good longitudinal data, predominantly European countries, recent years have shown a continuing decline in age-standardised IHD mortality. However, the progressive aging of populations has kept crude IHD mortality high. It is not known whether the pattern is consistent globally because many countries have not provided regular annual data including wealthy countries such as the United Arab Emirates and large countries such as India and China.     

Nutrition and the Aging Process: A Population Study

Highly significant correlations exist in the age range 35 to 84 years between log mortality from all causes and age, obtained from 33 countries (mean r equals 0.999 in men and 0.997 in women). Populations with a high life expectancy are characterized by a low intercept and a high slope of the equation between log mortality and age. The slope and intercept of the equation obtained from different countries are highly intercorrelated, pointing to a maximum life expectancy at the population level of about 104 years in men and 108 years in women. The slope of the equation between log mortality and age can be considered as an expression of the resistance against aging of a given population. Significant positive correlations exist between the level of saturated fat intake and the determinants of mortality at the population level. These correlations are more evident in men compared with women. The results offer evidence for a detrimental influence of saturated fat on the aging process in populations.