二、長壽時代的特徵及形成
B. Characteristics and causes of the age of longevity
（一）長壽時代的特徵
(a) Characteristics of the age of longevity
18世紀中期開始的工業革命打破了農業社會資源承載人口能力的限制，世界人口在那時開啓了前所未有的大規模成長。基於對人口成長過程中出生率和死亡率變化的研究，1929年美國人口學家沃恩·湯普森（Warren Thompson）提出按人口成長模式可以將各國劃分爲三類。在此基礎上，1945年弗蘭克·諾特斯坦（Frank Notestein）進一步將人口成長模式歸納爲潛在下降、轉變成長、潛在高成長三個類別。此後對於人口成長模式的描述逐步發展形成了人口轉變理論。當前普遍將人口轉變分爲四個階段，即第一階段是高出生率、高死亡率，人口規模不變或成長極其緩慢；第二階段是高出生率、死亡率下降，人口快速成長；第三階段是出生率下降、低死亡率，人口增速放緩；第四階段是低出生率、低死亡率，人口規模趨於穩定。
The Industrial Revolution which broke out in the mid-18th century shattered the constraint of the capacity of agricultural social resources to support the population, and the world』s population began to grow, on an unprecedented, massive scale. Based on research into changes in birth rates and mortality in the population growth process, US demographer Warren Thompson in 1929 first proposed dividing countries into three types based on population growth patterns. On this basis, Frank Notestein in 1945 further summarised the population growth pattern into three categories: incipient decline, transformational growth, and high growth potential. Since then, the description of population growth patterns has gradually developed into the theory of demographic transition. Today, demographic transition is generally divided into four stages, namely a first stage characterised by its high birth rate and mortality, and a lack of change or extremely slow growth in population size; a second stage then introduces a high birth rate but a decline in mortality, and rapid population growth; a third stage then witnesses a decline in the birth rate, low mortality, and a slowing population growth rate; finally, a fourth stage has a low birth rate and mortality, and the population size tends to stabilise.
當前世界正在由人口轉變的第三階段快速轉向第四階段，但第四階段以及之後會進入什麼狀態？我們在此提出長壽時代的概念，認爲它將是人口轉變後的新均衡。這一時代伴隨著五大特徵：低死亡率、低生育率、預期壽命持續提升、人口年齡結構趨向柱狀、平臺期老齡人口占比超越1/4。
The world is currently rapidly shifting from the third stage of the demographic transition to the fourth stage, but what state will we enter in this fourth stage and thereafter? Here, we would like to propose the concept of an age of longevity, and believe that this will form a new steady state following the demographic transition. This era will bring with it five major characteristics: low mortality, low fertility, continuously increasing life expectancy, a population age structure tending toward a pillar shape, and an ageing population segment which exceeds 1/4 of the total during the plateau period.
1.死亡率下降至低水準
1. Decline in mortality to low levels
19世紀人類的死亡率開始顯著下降。當時生活水準提高、營養改善是決定性的因素。工業革命帶來社會生產力水準大幅提升，使人們逐步擺脫了飢餓的困擾，增強了抵禦疾病的能力。英國和法國的預期壽命分別從1750年的37歲和26歲增至1900年的48歲和46歲。英國學者托馬斯·麥基翁（Thomas McKeown）提出19世紀英國死亡率下降是由於經濟和生活條件的改善，其中最重要的是飲食的改善（McKeown，1962）。美國學者羅伯特·福格爾（Robert Fogel）也提出人們對周圍環境的控制和創造技術革新的能力相互促進推動了死亡率的不斷降低（Fogel，2004）。
The 19th century saw the start of a marked decline in human mortality, which was mainly driven by improved living standards and nutrition. The Industrial Revolution brought about substantial increases in social productivity, gradually freeing people from hunger, and strengthening their resistance to disease. Between 1750 and 1900, life expectancy in the United Kingdom and France rose from 37 years and 26 years to 48 years and 46 years respectively. British scholar Thomas McKeown pointed out that the drop in mortality in the UK in the 19th century was attributable to improvements in economic and living conditions, the most important of which was the improvement in diet (McKeown, 1962). US scholar Robert Fogel also proposed that people』s control over their environment and the ability to create technological innovation mutually promoted the continuous decline in mortality (Fogel, 2004).
公共衛生條件的改善對死亡率的下降同樣扮演著重要的作用，尤其是對傳染性疾病的控制。以美國爲例，由於透過水和空氣傳播的傳染性疾病得到了有效控制，1900年至1940年美國整體死亡率下降了40%，預期壽命從47歲提升至63歲，原來在城市生活死亡率更高的問題也在這一時期消失了。研究發現淨水過濾和氯化系統的廣泛應用在其中發揮了巨大的作用，爲美國帶來了這一史無前例、最爲快速的死亡率下降（Cutler，2005）。此外，20世紀40年代抗生素類藥物的使用進一步降低了傳染病的病死率。例如，根據美國疾控中心數據顯示，在此期間肺結核的死亡率一下從1945年的39.9/10萬降到了1955年的9.1/10萬。
The improvement in public health conditions played a similarly significant role in the decline in mortality, particularly with regard to the control of communicable diseases. If we take the US as an example, the effective control of air- and water-borne communicable diseases brought about a 40% reduction in overall US mortality between 1900 and 1940, an increase in life expectancy from 47 years to 63 years, and the phenomenon that mortality used to be higher in urban areas also disappeared at this time. Studies have shown that the widespread use of clean water filtering and chlorination systems played a huge role in this, bringing a historically unprecedented, rapid drop in mortality to the USA (Cutler, 2005). Furthermore, the introduction of antibiotic drugs in the 1940s further reduced mortality from infectious diseases. For example, US Centers for Disease Control and Prevention data shows that the death rate from tuberculosis during this period dropped from 399 per million in 1945 to 91 per million in 1955.
到20世紀下半葉，醫療和技術進步與死亡率下降的關係越來越密切。有研究指出美國20世紀50年代以來死亡率下降更多是得益於醫療進步帶來的心臟病、中風等心血管疾病死亡率的降低。1950年至2016年美國預期壽命提升了11歲，其中一半以上的成長與65歲及以上人羣生存率提升有關（Catillon et al.，2018）。此外，歐美髮達國家在公共衛生方面的知識和現代醫藥技術向發展中國家的傳播推動了全球死亡率的快速下降。1960~2000年期間公共衛生基礎設施、免疫接種、疾病專項防治等成爲帶動發展中國家死亡率下降的重要因素，而收入和營養改善的影響已不像歐美髮達國家早期所經歷的那樣顯著（Soares，2007）。
During the latter half of the 20th century, the relationship between medical and technological progress and declining mortality became ever closer. Studies have shown that since the 1950s, the drop in mortality in the United States has been predominantly due to a decline in mortality thanks to medical progress in the treatment of cardiovascular diseases such as heart disease and stroke, inter alia. Between 1950 and 2016, life expectancy in the United States increased by 11 years, and more than half of this increase was related to the increased rate of survival in people 65 years and above (Catillon et al., 2018). In addition, awareness of public health in the developed nations of Europe and the Americas and the spread of modern medical technology to developing nations has driven a rapid decline in mortality worldwide. During the period from 1960-2000, public health infrastructure, immunisations, disease prevention and other measures have become major factors driving the drop in mortality in developing countries, although the impact of improvements in income and nutrition is no longer as significant as those previously experienced by the developed nations of Europe and the Americas (Soares, 2007).
新中國成立後，政府對衛生健康領域非常重視，並取得了巨大的成就，實現了死亡率的快速下降。20世紀50年代初期發起的全民衛生運動極大地改善了中國公共衛生狀況，顯著提升了對傳染病的防治能力。《中國婦幼健康事業發展報告（2019）》顯示，與解放前相比，到2018年中國孕產婦死亡率從1500/10萬下降到18.3/10萬，嬰兒死亡率從200‰下降到6.1‰，平均預期壽命從35歲提升至77歲（見圖1）。
Following the founding of the People』s Republic of China, the government attached great importance to hygiene and health, and has achieved tremendous results, bringing about a rapid reduction in mortality. The National Health Campaign, launched in the early 1950s, brought about a great improvement in China』s public health conditions, and significantly improved its ability to prevent and control infectious diseases. The China Maternal and Child Health Development Report (2019) shows that, when compared to the pre-1949 era, China』s maternal mortality rate dropped from 15 per thousand to 0.183 per thousand in 2018, while infant mortality dropped from 200 per thousand to 6.1 per thousand , and average life expectancy rose from 35 years to 77 years (see Figure 1).
2.生育率下降至低水準
2. Decline in fertility to low levels
在農業社會，人是最重要的經濟資源，孩子是生活保障和勞動力的來源，因此在高死亡率的生存環境下，高生育率是維持社會發展的需要。而工業革命的到來加速了城市化的進程，在這一過程中，女性的地位得到了根本性的提升，生育意願也因此發生了改變。
In agricultural society, people are the most important economic resource, and children are a source of social security and labour. This means that, in an environment with a high mortality rate, a high fertility rate is necessary to ensure social development. However, the onset of the Industrial Revolution accelerated the process of urbanisation. Part of this process saw a fundamental improvement in the status of women, and this in turn brought about changes in their desire to reproduce.
首先，兒童死亡率的顯著降低使人們對生育孩子數量的意願產生了變化。孩子的質量與父母在時間和金錢上的投入相關，夫妻在潛在生育孩子的供給量和需求量上需要尋求一個平衡（Becker，1960）。其次，女性受教育水準的不斷提升，增強了女性社會和工作參與的能力，改變了女性對生育的態度，在一定程度上也相應推遲了結婚和生育年齡。此外，對有效避孕知識的掌握和避孕工具的普及使兩性行爲與生育實現了分離。隨著20世紀60年代廉價、便捷的避孕藥在美歐及此後在全球的快速普及，有效的避孕工具變得簡單易得（保羅·莫蘭，2019）。
First of all, the significant drop in child mortality brought about a change in people』s willingness to have children. The quality of a child is partially determined by the amount of time and money invested by the parents, and partners must find a supply and demand balance in terms of the children that they may potentially have (Becker, 1960). Secondly, the continuous increase in the standard of women』s education has also enhanced their ability to participate in society and work, and this has brought about changes in women』s attitudes towards childbearing. To a certain degree, it has also delayed the age at which they marry and have children. In addition, a grasp of knowledge about contraceptives as well as the popularisation of contraceptive tools has also separated sexual activity from childbearing. With the rapid, widespread use of cheap and convenient contraceptive pill in the US, Europe and worldwide since the 1960s, effective contraception has become easy to obtain (Paul Morland, 2019).
20世紀70年代開始，生育率走低成爲全球性趨勢。不僅是發達國家，隨著低收入國家的發展，其生育率也隨之降低。1950~2017年所有國家和地區的總和生育率都出現了不同程度的下降，全球總和生育率下降了49.4%，由4.7個活產嬰兒降至2.4個（Murray et al.，2018）。另據聯合國中等假設水準預測，全球生育率還將繼續走低，到2050年每名婦女生育子女數將降至2.2個，到2100年降至1.9個。
Since the start of the 1970s, declining fertility has become a global trend. Developed nations have not been alone in this – as lower-income countries have developed, their fertility rates have also decreased. Between 1950 and 2017, there has been, to varying degrees, a decline in the total fertility rate in every single country and region. The global total fertility rate dropped by 49.4%, from 4.7 live births to 2.4 (Murray et al., 2018). In addition, according to United Nations medium variant assumption level forecasts, the global fertility rate will continue to decline: the number of children per woman will drop to 2.2 by 2050, and to 1.9 by 2100.
中國自20世紀70年代起經歷了生育率的快速下降，到1980年總和生育率已經從6左右降至3以下，到20世紀90年代已降至替代水準以下。這其中生育政策的影響只是一方面，實際上社會、人口、經濟的發展變化越來越成爲影響生育率的主導因素（都陽，2005）。近年中國二胎政策開放並沒有帶來生育率的回升，從國際經驗來看，一些低生育率國家鼓勵生育的政策也是需要漫長的時間積累纔可能看出成效（楊昕，2016）（見圖2）。
China has experienced a rapid drop in fertility since the 1970s. By 1980, total fertility rate had dropped from around 6 to below 3, and by the 1990s, had dropped further, to below the replacement level. However, the impact of fertility policy is only one aspect of this. In fact, social, demographic and economic developments have increasingly become the dominant factors impacting the fertility rate (Du Yang, 2005). In recent years, the launch of China's two-child policy has not brought about a resurgence in fertility. International experience has shown that policies to encourage childbirth in various low-fertility countries require plenty of time before the effects can be seen (Yang Xin, 2016) (see Figure 2).
圖2：世界、中國、日本、美國總和生育率變化趨勢
Figure 2: Trends in total fertility rates around the world, and in China, Japan and the USA
3.預期壽命持續延長
3. Life expectancy continues to increase
新興藥物的不斷創新、先進醫療技術的普及應用和進步使得心腦血管疾病、癌症、糖尿病、艾滋病等疾病逐漸從致死性的疾病殺手變成可控制的慢性疾病，人類的預期壽命得到持續延長，在過去半個多世紀裏，主要發達國家都保持了每十年成長2~3歲的趨勢。以癌症爲例，研究數據顯示，與1991年相比，2017年美國癌症死亡率已經下降了29%，其中2008年至2017年平均每年下降1.5%，2016年至2017年更是下降了2.2%，創歷年新高（Siegel et al.，2020）。
Continuous innovation in emerging pharmaceuticals, the widespread application of – and progress in – advanced medical technologies have gradually transformed cardio- and cerebrovascular diseases, cancer, diabetes, AIDS and other previously fatal diseases into controllable, chronic diseases, leading to ever greater human life expectancy. Over the past half-century, the major developed countries have all maintained a growth trend of 2-3 years every decade. To take cancer as an example, research data shows that when compared to 1991, the US cancer mortality rate in 2017 had dropped by 29%, including an average annual decrease of 1.5% between 2008 and 2017. In 2016 and 2017, this rate dropped even further, by 2.2%, a record high (Siegel et al., 2020).
從全球來看，1950年以來人口預期壽命顯著提升。1950~2017年全球男性預期壽命從48.1歲增至70.5歲，女性從52.9歲增至75.6歲（Dicker et al.，2018）。毫無疑問，人類的預期壽命還將保持穩步的成長，有預測研究指出到2040年全球男性和女性的預期壽命都將提升4.4年，屆時日本、新加坡、西班牙、瑞士有望超過85歲，另有59個國家也將超過80歲（Foreman et al.，2018）。需要指出的是，近年來有研究發現美國和英國的人均預期壽命出現輕微下降，這背後是由青年人濫用藥物、酗酒和自殺等社會問題引起，並不是老年人去世早了，也不能代表長期趨勢（Ho and Hendi，2018）。
The life expectancy of the global population has increased significantly since 1950. Between 1950 and 2017, global life expectancy increased from 48.1 years to 70.5 years for males, and from 52.9 years to 75.6 years for females (Dicker et al., 2018). There is no doubt that human life expectancy will continue to see steady growth, and some predictive studies indicate that by 2040, global life expectancy for both males and females will increase by 4.4 years. By that time, the figure in Japan, Singapore, Spain, Switzerland is expected to exceed 85 years, while that for a further 59 countries will also exceed 80 years (Foreman et al., 2018). It should however be noted that in recent years, studies have found that average life expectancy in the US and UK has decreased slightly. This is due to social problems such as drug and alcohol abuse, suicide amongst young people, rather than premature deaths amongst the elderly. Equally, this does not represent a long-term trend (Ho and Hendi, 2018).
在中國，伴隨著死亡率的快速下降，預期壽命也得到了大幅提升。20世紀60年代至20世紀70年代的20年間中國的預期壽命成長了22歲，之後以每10年成長約3歲的速度穩步提升，到2018年已達77歲。有研究預測到2040年中國預期壽命將達到81.9歲，也就是未來20年保持每十年成長約2.5歲的趨勢（Foreman et al.，2018）。儘管聯合國的預測相對保守，但是中國未來30年預期壽命仍將以平均每十年成長1.6~1.7歲的速度穩步提升（見圖3）。
In China, hand in hand with a rapid decline in mortality, life expectancy has also improved significantly. In the two decades from the 1960s to the 1970s, life expectancy in China grew by 22 years, and has since then continued a rapid, stable growth rate of approximately 3 years every decade. By 2018, the figure stood at 77 years. Some studies predict that by 2040, life expectancy in China will reach 81.9 years, that is to say, the country will maintain a growth trend of 2.5 years every decade over the next 20 years (Foreman et al., 2018). The relatively conservative United Nations forecast is that life expectancy in China will still continue to increase steadily at an average rate of 1.6-1.7 years per decade over the next 30 years (see Figure 3).
對於人類壽命是否存在成長的極限，目前尚無定論。有研究回顧1900年以來多國數據後提出人類的壽命受各種自然因素的限制是存在天花板的（Dong et al.，2016）。但是也有研究發現當年齡超過105歲之後，死亡風險水準基本上不再變化，死亡率不再隨著年齡增大而上升（Barbi et al.，2018）。從經驗角度看，經濟、社會、醫學的發展會不斷推動人類壽命延長，人類的預期壽命可以持續地成長（Oeppen and Vaupel，2002；Vaupel and Kistowski，2005）。
Whether there is any limit to the human lifespan remains open to conjecture. Some studies which reviewed data from numerous countries from 1900 onward suggest that the human lifespan is limited by a number of natural factors, and that there is a ceiling (Dong et al., 2016). However, other studies have also found that at ages in excess of 105 years, the risk of death essentially does not change any further, and the mortality rate does not continue to increase with age (Barbi et al., 2018). From an empirical point of view, economic, social and medical developments will continue to drive the extension of the human lifespan, and human life expectancy can continue to rise (Oeppen and Vaupel, 2002; Vaupel and Kistowski, 2005).
4.人口年齡結構趨向「柱狀」，老齡人口占比高峯平臺期超越1/4
4. The population age structure has become 「pillar-shaped」, with more than a quarter of the elderly population in a plateau period
在死亡率和生育率下降的雙重作用下，世界人口增速放緩，全球的人口年齡結構在由傳統的金字塔形態向柱狀轉變，即各年齡段人口占比向均等化發展，老齡人口與青少年人口數量均等化（Haub，2013）。從更爲長期的角度看，由於生育率的持續下降，人口年齡結構還可能出現倒梯形。
Impacted by the dual effects of the decline in mortality and fertility, the world』s population growth rate has slowed, and the age structure of the global population has shifted from a traditional pyramid shape to a pillar shape, that is, where the proportions of the population for all age segments develop at the same pace, and the numbers for the elderly and young populations are equal (Haub, 2013). From a longer-term perspective, a continued decline in fertility may even mean that the population age structure takes on an inverted trapezoid shape.
聯合國數據顯示，1960~2020年，全球0~14歲少兒人口占比不斷下降，由37.2%降至25.4%；65歲及以上老齡人口占比持續上升，由5.0%增至9.3%，並且預計在50年後二者將趨於均等。同時，在過去的60年間各國人口年齡結構轉變的速度有所不同，例如美國在移民持續湧入的影響下，人口年齡中位數由29.7歲增至38.3歲，只成長了8.6歲；而日本受生育率快速下降且長期低迷的影響，人口年齡中位數由25.4歲躍升至48.4歲，成長達23.0歲。相比世界平均水準，中國人口年齡結構也發生了較快的轉變。1960~2020年人口年齡中位數從21.3歲增至38.4歲，其中1960年至1990年只增加了3.6歲，而1990~2020年成長了13.6歲。
United Nations data shows that from 1960-2020, the proportion of the world』s child population aged 0-14 years declined continuously, from 37.2% to 25.4%. Conversely, the proportion of the population aged 65 years and above has continued to increase, from 5.0% to 9.3%, and it is estimated that 50 years later these two proportions will be close . At the same time, over the past 60 years, the rates of change in the population age structure for each country have varied widely. For example, in the US, under the impact of a continuous wave of immigration, the median age of the population increased from 29.7 years to 38.3 years, an increase of only 8.6 years. Meanwhile, in Japan, affected by a rapid decline in fertility and a long-term economic downturn, the median age of the population jumped from 25.4 years to 48.4 years, an increase of 23.0 years. Compared with the world average, the age structure of China』s population has also undergone rapid transformation. From 1960 to 2020, the median age of the population increased from 21.3 years to 38.4 years. From 1960 to 1990, the increase was a mere 3.6 years, whereas it grew by 13.6 years between 1990 and 2020.
經濟學上將由於勞動年齡人口數量和佔比成長快於其他年齡組人口所帶來的經濟成長稱爲人口紅利（demographic dividend）（Bloom et al.，2003）。它通常發生在人口轉型的第三階段末，因爲此時生育率發生快速下降使得受撫養的青幼年人口明顯減少（Bloom and Williamson，1998）。新中國成立後的前20年死亡率大幅下降，而生育率繼續保持高水準直至20世紀70年代初纔開始明顯降低，這使得改革開放後勞動年齡人口出現了爆發性成長，撫養比下降、勞動力供給充分帶來的人口紅利推動了中國的高速發展。然而，隨著人口年齡結構的進一步轉變，中國的人口紅利在快速消退。國家統計局數據顯示，中國的總撫養比在2010年已降至低點，2013年勞動年齡人口也已達到峯值。伴隨著死亡率、生育率降至低水準並趨於穩定，預期壽命穩步提升，老齡人口占比增加，中國的人口年齡結構開始日漸趨於柱狀（見圖4）。
In economic terms, the economic growth generated because the number and proportion of the working age population grew faster than any other age group is called the demographic dividend (Bloom et al., 2003). This normally occurs at the end of the third stage of the demographic transition, as the rapid decline in fertility at this time significantly reduces youth dependent population (Bloom and Williamson, 1998). In the 20 years following the foundation of the People』s Republic of China, mortality dropped sharply, while fertility remained high until the early 1970s, after which it began to decline significantly. This led to the explosive growth of the working-age population following the start of the reform and opening up process, a drop in the dependency ratio, and the democratic dividend from China』s full labour force drove the country』s high-speed development. However, with the further transformation of the population age structure, China』s demographic dividend is fading rapidly. National Bureau of Statistics data shows that China's total dependency ratio had fallen to a low point by 2010, while the working-age population also peaked in 2013. With mortality and fertility at low levels and stabilising, and a steady increase in life expectancy, the proportion of the elderly population is increasing, and China's population age structure has started to take on an increasingly pillar-shaped appearance (see Figure 4).
大多數經歷人口轉變第三階段的國家都出現過或長或短的嬰兒潮，之後生育率便急速下降。當嬰兒潮老去，正好也是人口跨越第三階段達到第四階段的時候。低死亡率、壽命延長、生育率驟降造成了後期老齡人口的快速成長，經歷過大幅嬰兒潮的國家，老齡人口占比都會加速超越總人口的1/4，並且在達到峯值後，由於穩定的低生育率和預期壽命的持續延長，其比例會保持相對穩定。
Most countries which have undergone the three-stage demographic transition have experienced baby booms of varying lengths, after which the fertility rate has dropped sharply. The time that baby boomers get older is also precisely the time when the population crosses from the third stage into the fourth stage. Low mortality, extended lifespans and a sudden drop in the fertility rate lead to the rapid growth of the elderly population in the latter stage. In countries that have experienced large baby booms, the elderly proportion of the population accelerates to exceed one quarter of the total population, and after peaking, this proportion remains relatively stable because of stable, low fertility and continuous rising life expectancy.
與這個規律相符合，中國老齡人口數量及其佔比正在進入快速成長期。國家統計局數據顯示，2019年中國人口達到14億，其中65歲及以上1.76億，佔比達到12.6%。2017年、2018年、2019年，65歲及以上人口分別新增828萬、827萬、945萬。聯合國預測，中國65歲及以上人口還將繼續保持高位成長，直至2040年之後年均增幅纔會降至500萬人以下。到2057年65歲及以上人口與80歲及以上人口數量有望達到峯值，分別爲4.0億和1.3億，佔29.6%和9.8%。同時，從全球視角來看，中國是世界老齡人口數量最多的國家，2030年左右中國65歲及以上人口在全球老齡人口的佔比將超過25%（見圖5）。
In line with this law, both the number and proportion of China』s elderly population are entering a period of rapid growth. National Bureau of Statistics data shows that China』s population reached 1.4 billion in 2019, of which 176 million were aged 65 years and above, making up 12.6% of the total. In 2017, 2018 and 2019, the population aged 65 years and above increased by 8.28 million, 8.27 million and 9.45 million respectively. The United Nations predicts that China』s population aged 65 years and above will continue to maintain a high rate of growth, and the annual rate of growth will not fall below 5 million before 2040. The population aged 65 years and above and the population 80 years and above are expected to peak by 2057, at 400 million and 130 million respectively, accounting for 29.6% and 9.8% of the total. At the same time, from a global perspective, China is the country with the largest number of elderly people in the world. By 2030 or so, China』s population aged 65 years and above will make up in excess of 25% of the world』s elderly population (see Figure 5).
圖5：中國65歲及以上與80歲及以上人口占總人口比例變化趨勢
Figure 5: Trends in the proportion of China』s population aged 65 years and 80 years and above to the total population
（二）長壽時代與健康時代
(b) The age of longevity and age of health
在長壽時代，人類的預期壽命獲得延長，同時也面臨著與之前完全不同的健康挑戰。健康成爲更爲迫切的需求，且這種需求將更加多樣化和長期化，成爲健康產業成長的強勁動力，健康時代隨之來臨。
In the age of longevity, life expectancy will rise, but at the same time, we will also face health challenges which are entirely different than before. Health becomes a more pressing need, and this need will become ever more diversified and long-term. This will become a powerful engine driving health industry growth, ushering in an age of health.
1.長壽時代疾病譜發生重大改變
1. Significant changes in the disease spectrum in the age of longevity
人類疾病類型的流行病學轉變（Epidemiological Transition）（Omran，1977）與長壽時代同步來臨。2002年召開的第二次世界老齡大會就已經指出，當時全球各區域都正處於流行病學轉變的階段，即從主要罹患傳染性疾病和寄生蟲病爲主轉向罹患慢性疾病和變性疾病爲主（宋新明，2003）。
The epidemiological transition of human disease types (Omran, 1977) and the age of longevity arrive hand in hand. The Second World Assembly on Ageing held in 2002 highlighted the fact that at the time, all of the world』s regions were in a stage of epidemiological transition, that is to say, they were shifting from infectious and parasitic diseases as the main sources of infection to a situation where chronic and degenerative diseases prevail (Song Xinming, 2003).
華盛頓大學健康指標與評估研究所（IHME）2017年對195個國家和地區的研究表明：1990~2017年，新生兒疾病、腸道感染、呼吸道感染、結核病等傳染性疾病導致的過早死亡人數下降，而缺血性心臟病、中風、慢阻肺等慢性病、老年性疾病則大幅上升，特別是缺血性心臟病成爲全球首要致死原因（Roth et al.，2017）。（見表1）
A 2017 study of 195 countries and regions by the Institute for Health Metrics and Evaluation (IHME) of the University of Washington shows that between 1990 and 2017, whereas the numbers of premature deaths from infectious diseases such as neonatal diseases, intestinal infections, respiratory tract infections and tuberculosis had dropped, chronic diseases such as ischemic heart disease, stroke and chronic obstructive pulmonary disease, as well as senile diseases increased significantly, and ischemic heart disease in particular had become the leading cause of death worldwide (Roth et al., 2017) (See Table 1).
中國也正在面臨同樣的轉變，中國1990~2017年致死和生命損失疾病譜前五名已經從傳染性疾病、新生兒疾病等急性疾病、兒童期疾病轉變爲心腦血管疾病、腫瘤、退行性疾病等慢性病、老年性疾病（Zhou et al.，2019）。（見表2）
China is also facing the same transformation. Between 1990 and 2017, the top five causes of fatality in China changed from infectious, neonatal and other acute or childhood diseases to cardiovascular and cerebrovascular diseases, tumours, degenerative diseases and other chronic and senile diseases (Zhou et al., 2019) (See Table 2).
正是因爲流行病學的轉變，人類平均預期壽命延長的最大威脅已經從傳染性疾病轉移到衰老導致的退行性和人爲疾病（如：道路傷害、意外死亡等），那些慢性退行性疾病未來隨著人類生活方式變得更加健康、醫療技術創新加快、最終死亡年齡的延長，將在長壽時代與人類共存更長時間。
It is precisely because of this change in epidemiology that the greatest threat to the rise in average human life expectancy has shifted from infectious diseases to degenerative diseases caused by ageing and man-made diseases (e.g.: road injuries, accidental death, etc.). Chronic degenerative diseases of this kind will remain prevalent in humans for relatively longer periods of time in the age of longevity as human lifestyles become ever healthier, innovation in medical technology accelerates, and the final age of death is further extended.
各類非傳染性慢性病正成爲人類長壽健康損失的主要原因。根據世界衛生組織（WHO）的定義，傷殘調整生命年（DALY）用來估量由於各種致命及非致命疾病所導致的健康損失，它等於壽命損失年數（YLL）與殘疾生命年數（YLD）之和（Murray，1994）②。使用華盛頓大學健康指標與評估研究所數據計算的結果表明：從1970年到2016年之間，傳染病以及營養不良所導致的健康損失下降了40.1%，與之對應的各種非傳染性慢性病所導致的健康損失卻整體增加了36.6%，其中心血管疾病成長了32.4%、神經系統疾病成長了59.4%；同期全球範圍內80歲以上人口貢獻的健康損失成長了98%（Wang et al.，2017）。同篇數據顯示，老齡人口的增加給中國帶來的健康損失情況比全球平均水準更爲嚴峻。
Various types of non-communicable, chronic disease are becoming the main factor behind the loss of human longevity and health. Based on the World Health Organisation (WHO) definition, the disability-adjusted life year (DALY) is used to estimate the health loss caused by various fatal and non-fatal diseases. It is equal to the sum of the years of lost life (YLL) and years lived with disability (YLD) (Murray, 1994) (2). Using the calculation results from the data from the University of Washington』s Institute for Health Metrics and Evaluation, we find that from 1970 to 2016, the loss of health caused by infectious diseases and malnutrition dropped by 40.1%, while conversely, the loss of health caused by various non-communicable chronic diseases increased by 36.6% overall, of which cardiovascular disease grew by 32.4%, and neurological diseases grew by 59.4%. Over the same period, the loss of health contributed by the population aged 80 years and above grew by 98% (Wang et al., 2017). The same data shows that the loss of health to China caused by the elderly population is more severe than the global average.
