Inequality in Life Spans and a New Perspective on Mortality Convergence Across Industrialized Countries

The second half of the twentieth century witnessed substantial convergence in life expectancy around the world. We examine differences in the age pattern of mortality in industrialized countries over time to show that inequality in adult life spans, which we measure with the standard deviation of life table ages at death above age 10 years, S₁₀, is increasingly responsible for the remaining divergence in mortality. We report striking differences in level and trend of S₁₀ across industrialized countries since 1960, which cannot be explained by aggregate socioeconomic inequality or differential external‐cause mortality. Rather, S₁₀ reflects both within‐ and between‐group inequalities in life spans and conveys new information about their combined magnitudes and trends. These findings suggest that the challenge for health policies in this century is to reduce inequality, not just lengthen life.     

Mortality in Quebec during the nineteenth century: from the state to the cities

The aim of this paper is to explore mortality in Quebec during the nineteenth century from a demographic perspective. During the nineteenth century, there was excess urban mortality in various countries; in order to identify such mortality differentials, we compared mortality indicators for the province of Quebec and then for the urban areas of Montreal and Quebec City. Using data from various studies, we produced life tables and compared life expectancies. We show that at different times during the nineteenth century, spatial variations in mortality levels across the province of Quebec and its urban areas were significant. According to the data we analyzed, mortality is undoubtedly higher in urban areas even though a convergence in trends took place towards the end of the century, resulting in an overall reduction in mortality. Also, exploring life expectancies within a cohort approach at times of fast-changing mortality patterns has proved to be instructive. Life expectancy estimates based on a cross-sectional approach were systematically lower than those resulting from a cohort-specific one. Trends diverged to a greater extent beginning with the 1870 cohort, reflecting the improvements made from that point on to World War II. Since current mortality levels are substantially determined by the cumulative effects of past behaviour specific to each generation, it is quite obvious that mortality analysis will reveal its true meaning only with the help of cohort life tables.     

The implications of increased survivorship for mortality variation in aging populations

The remarkable growth in life expectancy during the twentieth century inspired predictions of a future in which all people, not just a fortunate few, will live long lives ending at or near the maximum human life span. We show that increased longevity has been accompanied by less variation in ages at death, but survivors to the oldest ages have grown increasingly heterogeneous in their mortality risks. These trends are consistent across countries, and apply even to populations with record-low variability in the length of life. We argue that as a result of continuing improvements in survival, delayed mortality selection has shifted health disparities from early to later life, where they manifest in the growing inequalities in late-life mortality.     

The Trend in International Health Inequality

Estimates of average life expectancy for 169 countries are used to compute the trend in between‐country health inequality from 1980 to 2000. Results show that inequality in the distribution of life expectancy across countries declined in the 1980s, but then increased through the 1990s. The recent turnaround in between‐country health inequality is significant because it reverses a long‐term trend of declining inequality across countries that began in the first half of the twentieth century. The primary cause of rising inequality across countries is declining life expectancy in sub‐Saharan Africa, largely owing to HIV/AIDS. Life expectancy in sub‐Saharan Africa holds the key to the future trend in between‐country inequality.     

The cost of uncertain life span

Much uncertainty surrounds the length of human life. The standard deviation in adult life span is about 15 years in the USA, and theory and evidence suggest that it is costly. I calibrate a utility-theoretic model that shows that 1 year in standard deviation is worth about half a life year. Differences in variance exacerbate health inequalities between and among rich and poor countries. Accounting for the cost of life-span variance appears to amplify recently discovered patterns of convergence in world average human well-being because the component of variance due to infant mortality has exhibited even more convergence than life expectancy.     

HIV/AIDS and Cross-National Convergence in Life Expectancy

This article analyzes the effect of HIV/AIDS on the cross-national convergence in life expectancy as well as infant and child survival rates by comparing three scenarios. One is based on historical and future best-guess estimated values given the existence of the epidemic. The second scenario assumes that the effect of the epidemic is much worse than expected. The final scenario is based on hypothetical values derived from estimations where the mortality caused by the epidemic is removed. For life expectancy, convergence becomes stalled in the late 1980s (without weighting by country population size) or 1990s (with weighting). Convergence in infant and child survival rates does not become stalled, but slows down. These results are mainly attributable to the epidemic since all signs of stalled convergence or even divergence disappear in the “No AIDS scenario.” Given the existence of the epidemic, however, the reduced degree of inequality in life expectancy attained by 1985 is only expected to be achieved again by 2015 at the earliest. If the epidemic turns out much worse than expected, divergence could continue to 2050. No divergence is to be expected in infant and child survival rates in any of the scenarios.     

The Contribution of Drug Overdose to Educational Gradients in Life Expectancy in the United States, 1992–2011

Since the mid-1990s, the United States has witnessed a dramatic rise in drug overdose mortality. Educational gradients in life expectancy widened over the same period, and drug overdose likely plays a role in this widening, particularly for non-Hispanic whites. The contemporary drug epidemic is distinctive in terms of its scope, the nature of the substances involved, and its geographic patterning, which influence how it impacts different education groups. I use vital statistics and National Health Interview Survey data to examine the contribution of drug overdose to educational gradients in life expectancy from 1992–2011. I find that over this period, years of life lost due to drug overdose increased for all education groups and for both males and females. The contribution of drug overdose to educational gradients in life expectancy has increased over time and is greater for non-Hispanic whites than for the population as a whole. Drug overdose accounts for a sizable proportion of the increases in educational gradients in life expectancy, particularly at the prime adult ages (ages 30–60), where it accounts for 25 % to 100 % of the widening in educational gradients between 1992 and 2011. Drug overdose mortality has increased more rapidly for females than for males, leading to a gender convergence. These findings shed light on the processes driving recent changes in educational gradients in life expectancy and suggest that effective measures to address the drug overdose epidemic should take into account its differential burden across education groups.     

Age-Specific Variation in Adult Mortality Rates in Developed Countries

This paper investigates historical changes in both single-year-of-age adult mortality rates and variation of the single-year mortality rates around expected values within age intervals over the past two centuries in 15 developed countries. We apply an integrated hierarchical age-period-cohort—variance function regression model to data from the human mortality database. We find increasing variation of the single-year rates within broader age intervals over the life course for all countries, but the increasing variation slows down at age 90 and then increases again after age 100 for some countries; the variation significantly declined across cohorts born after the early 20th century; and the variation continuously declined over much of the last two centuries but has substantially increased since 1980. Our further analysis finds the recent increases in mortality variation are not due to increasing proportions of older adults in the population, trends in mortality rates, or disproportionate delays in deaths from degenerative and man-made diseases, but rather due to increasing variations in young and middle-age adults.     

近50年来世界人口期望寿命的演变轨迹

进入21世纪以来,全球人口已经突破60亿,但是人口增长速度明显减慢。许多国家已经完成了人口转变,其总和生育率在更替水平以下。与此同时,人口健康状况得到明显改善,死亡水平显著降低,期望寿命在不断提高。本文利用联合国人口司发布的192个国家人口死亡信息,系统分析了世界人口平均期望寿命在过去50年里的演变态势、区域差异以及演变模式。结果显示世界人口期望寿命经历了半个多世纪的持续增长,有50%以上的人口或国家平均期望寿命达到了70岁。演变轨迹呈多样化的发展模式,区域发展不平衡。欠发达地区总体上较发达地区增幅大,人口比重上升幅度也很显著。人均期望寿命增幅最大的是亚洲国家,非洲国家与世界不同步,而且区域内差异较大。     

Vocational Status,Hukou and Housing Migrants in the New Century: Evidence from a Multi-city Study of Housing Inequality

In the 1960s and 1970s, the countries of Central and Eastern Europe and the Soviet Union experienced an unanticipated stagnation in the process of mortality reduction that was accelerating in the west. This was followed by even starker fluctuations and overall declines in life expectancy during the 1980s and 1990s. We identify statistically the extent to which, since the 1990s, the countries of the post-communist region have converged as a group towards other regional or cross-regional geopolitical blocks, or whether there are now multiple steady-states (‘convergence clubs’) emerging among these countries. We apply a complex convergence club methodology, including a recursive analysis, to data on 30 OECD countries (including 11 post-communist countries) drawn from the Human Mortality Database and spanning the period 1959–2010. We find that, rather than converging uniformly on western life expectancy levels, the post-communist countries have diverged into multiple clubs, with the lowest seemingly stuck in low-level equilibria, while the best performers (e.g. Czech Republic) show signs of catching-up with the leading OECD countries. As the post-communist period has progressed, the group of transition countries themselves has become more heterogeneous and it is noticeable that distinctive gender and age patterns have emerged. We are the first to employ an empirical convergence club methodology to help understand the complex long-run patterns of life expectancy within the post-communist region, one of very few papers to situate such an analysis in the context of the OECD countries, and one of relatively few to interpret the dynamics over the long-term.     

A generalization of life expectancy which incorporates the age distribution of the population and its use in the measurement of the impact of mortality reduction

Two new families of indices measuring the gain in life expectancy resulting from reduction in mortality are introduced: the first looks at the impact of cause of death reduction from the perspective of the entire population; the second, at that segment of the population due to die of the cause. Special cases include both well-established measures and extensions that incorporate the age distribution of the population. A further generalization is introduced with the consideration of life expectancies that only give weight to years of life up to age 70. A number of inequalities are derived that relate cause-deleted life expectancies to their cause-reduced counterparts.     

How Long Do We Live?

Period life expectancy is calculated from age‐specific death rates using life table methods that are among the oldest and most widely employed tools of demography. These methods are rarely questioned, much less criticized. Yet changing age patterns of adult mortality in countries with high life expectancy provide a basis for questioning the conventional use of life tables. This article argues that when the mean age at death is rising, period life expectancy at birth as conventionally calculated overestimates life expectancy. Estimates of this upward bias, ranging from 1.6 years for the United States and Sweden to 3.3 years for Japan for 1980–95, are presented. A similar bias in the opposite direction occurs when mean age at death is falling. These biases can also distort trends in life expectancy as conventionally calculated and may affect projected future trends in period life expectation, particularly in the short run.     

Changing sex differences in life expectancy in Australia between 1970 and 1990

Between 1970 and 1990, Australia experienced a narrowing of its sex difference in life expectancy by just over one year, which is a substantial amount when compared to the experience of other industrialized nations. Most of this reduction materialized in the decade between 1980 and 1990. In this study we decompose the gender based survival difference in 1970, 1980 and 1990 into components that can be attributed to different causes of death. Our analysis indicates that a significant component of the constriction in the differential was due to males having made larger gains than females over time with respect to heart disease, accidents and violence excluding suicide, and lung cancer. A large part of the narrowing in female-male difference in life expectancy can be attributed to narrowing sex differences in mortality in the older ages. We discuss these findings in the context of emerging epidemiological trends in the industrialized world, and the implications these have for the future of the sex differential in survival.     

Three measures of longevity: Time trends and record values

This article examines the trend over time in the measures of “typical” longevity experienced by members of a population: life expectancy at birth, and the median and modal ages at death. The article also analyzes trends in record values observed for all three measures. The record life expectancy at birth increased from a level of 44 years in Sweden in 1840 to 82 years in Japan in 2005. The record median age at death shows increasing patterns similar to those observed in life expectancy at birth. However, the record modal age at death changes very little until the second half of the twentieth century: it moved from a plateau level, around age 80, to having a similar pace of increase as that observed for the mean and the median in most recent years. These findings explain the previously observed uninterrupted increase in the record life expectancy. The cause of this increase has changed over time from a dominance of child mortality reductions to a dominance of adult mortality reductions, which became evident by studying trends in the record modal age at death.     

On the scale of global demographic convergence, 1950-2000

The second half of the twentieth century saw global demographic change of unprecedented magnitude, with pronounced falls in both mortality and fertility in many developing countries. This article assesses the extent to which these changes have led to the convergence of demographic patterns around the world. It considers not just the levels of fertility and mortality in each country at different points in time, but also the size of each population. It also disaggregates China and India into their constituent provinces and states in order to provide estimates for units more typical of the size of the populations of other countries. The note presents proportions of the world's population according to the levels of life expectancy and total fertility they experienced in the early 1950s, the late 1970s, and around 2000. The graphs and tables thus produced give a convenient and novel way to view the scale and nature of demographic convergence over the last 50 years.     

Change in disability-free life expectancy for Americans 70 years old and older*

In this article, we examine changes in life expectancy free of disability using longitudinal data collected from 1984 through 2000 from two cohorts who composed the Longitudinal Studies of Aging I and II. Life expectancies with and without ADL and/or IADL disability are calculated using a Markov-based multistate life table approach. At age 70, disability-free life expectancy increased over a 10-year period by 0.6 of a year in the later cohort, which was the same as the increase in total life expectancy, both increases marginally statistically significant. The average length of expected life with IADL and ADL disability did not change. Changes in disability-free life expectancy resulted from decreases in disability incidence and increases in the incidence of recovery from disability across the two survey cohorts. Age-specific mortality among the ADL disabled declined significantly in the later cohort after age 80. Mortality for the IADL disabled and the nondisabled did not change significantly. Those with ADL disability at age 70 experienced substantial increases in both total life expectancy and disability-free life expectancy. These results indicate the importance of efforts both to prevent and delay disability and to promote recovery from disability for increasing life expectancy without disability. Results also indicate that while reductions in incidence and increases in recovery work to decrease population prevalence of disability, declining mortality among the disabled has been a force toward increasing disability prevalence.     

Differences in life expectancy by education and occupation in Italy, 1980-94: indirect estimates from maternal and paternal orphanhood

In the present study, we use the modified orphanhood method to analyse mortality differences by socio-economic status in Italy. This technique permits the indirect estimation of adult mortality from survey-based information on parents' survival in developed populations and helps to overcome several limitations of conventional studies on mortality differences by social class. We estimate a time series of life tables by education and occupation and analyse the differences in life expectancy by socio-economic status along with their changes between 1980-84, 1985-89, and 1990-94. Whereas mortality differences between the highest social class and the other socio-economic status groups increased among men, they decreased among women. We speculate about the reasons for these sex-specific trends and evaluate the application of indirect estimation techniques to the populations of developed countries.     

A state-based regression model for estimating substate life expectancy

Life expectancy is an important indicator of the level of mortality in a population. However, the conventional way of calculating life expectancy--constructing a life table--has rigorous data requirements. As a consequence, life expectancy data are not usually available for substate areas. In this article, a regression model for estimating life expectancy is constructed, using state-level data, and is tested against two sets of 1980 life expectancy data: (1) a nationwide sample of metropolitan areas and (2) selected cities, their suburbs, and rural counties in Ohio. An additional test shows the sensitivity of the model's accuracy to errors in one of its input data elements. The results suggest that the model should be given serious consideration for generating life expectancy estimates for substate areas.     

Future life expectancy in Australia,Europe, Japan and North America

Human life expectancy has risen in most developed countries over the last century, causing the observed demographic shifts. Babel, Bomsdorf and Schmidt (forthcoming) introduce a stochastic mortality model using panel data procedures which distinguishes between a common time effect and a common age effect of mortality evolvement. Using this mortality model, the present paper provides forecasts of future life expectancy for 17 countries divided into 12 regions: Australia, Alps, Bene, Canada, England and Wales, France, Germany, Italy, Japan, Spain, Scandinavia and the United States of America. We consider (traditional) period life expectancies as well as cohort life expectancies, the latter being a more realistic approach but less common. It turns out that a continuing increase of life expectancy is expected in all considered countries. Further, we show that the probabilistic uncertainty of forecast life expectancies is different if either period life expectancies or cohort life expectancies are considered and, moreover, the uncertainty increases substantially if the error of parameter estimation is included.     

Changing mortality and morbidity rates and the health status and life expectancy of the older population

This paper demonstrates the consequences of changes in mortality and health transition rates for changes in both health status life expectancy and the prevalence of health problems in the older population. A five-state multistate life table for the mid-1980s provides the baseline for estimating the effect of differing mortality and morbidity schedules. Results show that improving mortality alone implies increases in both the years and the proportion of dependent life; improving morbidity alone reduces both the years and the proportion of dependent life. Improving mortality alone leads to a higher prevalence of dependent individuals in the life table population; improving morbidity alone leads to a lower percentage of individuals with problems in functioning.