Introduction
Life expectancy at birth has increased substantially over the course of human history, mostly because of reductions in infant and child mortality, themselves a result of a reduction in infectious disease mortality. Since the 1970s, the main factor driving continued gains in life expectancy in high-income countries has been the decrease in mortality in older people, specifically deaths from non-communicable diseases.1 Most analyses of worldwide patterns of adult mortality have focused on the age group 15–59 years; analyses for people aged 60 years and older have tended to focus only on high-income countries.2 We aimed to provide a comprehensive overview of mortality and life expectancy and their trends at older age. We define older adults here as aged 60 years or older.
Key messages
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High quality data for levels of and trends in older age (>60 years) mortality are unavailable for all low-income and many middle-income countries
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Life expectancy at age 60 years has improved steadily in the past three decades, with no deceleration in life expectancy improvement or consistent compression in age at death
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For men in high-income countries, the risk of dying between ages 60 years and 80 years has been decreasing at 1·5% a year on average during the past three decades, the same as the average rate of decrease of 1·5% per year for the risk of dying between ages 15 years and 60 years
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For women, the risk of dying between ages 60 years and 80 years has been decreasing at an average annual rate of 1·7%, faster than the risk of dying between ages 15 years and 60 years (1·2% per year)
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The annual average rate of increase in life expectancy at age 80 years was slightly higher for both men and women than that of age 60 years
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Improvements in older age mortality were mainly atrributed to decreases in tobacco use (for men) and in cardiovascular disease mortality (for both men and women)
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Older age mortality can be assessed by comparison with mortality in best-performing so-called frontier countries. Whenever mortality rates are higher than those in the frontier countries, the difference in mortality can be judged avoidable
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Male avoidable mortality has fallen in high-income countries during the past three decades. However, both female avoidable mortality in all regions and male avoidable mortality in middle-income countries have changed little or risen since 1980. Particularly, avoidable mortality in middle-income European countries has increased, showing that these countries are falling behind the best-performing ones
WHO has estimated life average expectancy at age 60 years for all Member States during the years 1990–2012.3 Most countries in the Middle East, north Africa, and sub-Saharan Africa do not have usable death registration data, and estimates of mortality at older age rely on the use of model life tables to extrapolate from younger adult mortality and, in some countries, from other sources of mortality data (panel). WHO has estimated that worldwide average life expectancy for women at age 60 years was 21·5 years in 2012, ranging from 17·2 years in sub-Saharan Africa to 26·1 years in high-income countries (table). For men, the worldwide life expectancy at age 60 years was 18·5 years, ranging from 15·7 years in sub-Saharan Africa to 22·3 years in high-income countries. During the past two decades, life expectancy at age 60 years for men and women has risen by 0·9 years for men and 0·8 years for women per decade. The gap in life expectancies between high-income and low-income and middle-income countries has grown. Life expectancy in high-income countries has increased by 1·6 for men and 1·4 years for women per decade compared with 0·7 years for men and 0·8 years for women in low-income and middle-income countries.
We explored these trends in more detail using high quality death registration data. We addressed the following questions: how do recent gains in older adult life expectancy vary by country and region? Is a fixed upper limit for the human life span approaching, with the consequent compression of mortality into a narrowing band of older ages, as proposed by Fries?23 What are the causes of the recent decreases in death rates in older people? Is there potential for further reductions in mortality at older ages, from which causes, and in which countries and regions? We decided that reliable information on cause-specific mortality and their trends could be calculated from death registration data in the WHO mortality database24 if the proportion of all deaths (recorded and unrecorded) for which cause-of-death information could be obtained exceeded 80% for at least 80% of data-years available between 1980 and 2011. The appendix describes selection criteria for countries and methods for data adjustment, interpolation, and extrapolation for missing country years. After exclusion of data series that did not meet quality criteria, and interpolation and extrapolation, our final dataset contained complete (or nearly complete) time series from 1980 to 2011 for 51 countries (appendix). These countries were predominantly high income countries, but the dataset included middle income countries in Europe and Latin America and the Caribbean (appendix). We refer to data meeting the inclusion criteria as high quality; this definition does not necessarily imply that coding of cause or age of death are highly accurate.