Dora Costa. 2013. Health and the economy in the United States, form 1750 to the present. Working Paper 19685. National Bureau of Economic Research

http://www.nber.org/papers/w19685

       Abstract: This review discusses theories of the health transition and examines how the health transition occurred in the United States, including changes in the distribution of health by socioeconomic status. I bring new data to bear on an extensive array of health indicators -- mortality, height, BMI, birth weight, and chronic conditions. I investigate the role in the health transition played by rising incomes and by scientific advances and their application and I will argue that the preponderance of the evidence shows that scientific advances have played an outsize role in the United States. I will examine how these scientific advances, which during the health transition took the form of expensive sanitation projects, were implemented. Fear of infection provided the political support for the financing of these projects, even when the poor were the primary beneficiaries. Because more recent scientific advances have taken the form of therapies targeted to chronic disease and because the importance of behavioral factors has grown, political support for expenditures aimed at the poor is likely to be lower. I will argue that while improvements in health raise productivity, these improvements are not necessarily a precondition for modern economic growth. The nature of the economy in which these improvements occur also matters. The gains to early life health are largest when the economy has moved from “brawn” to “brains” because this is when the wage returns to education are high, leading the healthy to obtain more education. Although the causal effect of education on health is still unclear, those who obtain more education may be better able to take advantage of new medical knowledge and therapies as they age. Analyses and theories of health therefore need to treat health as a dynamic variable. The review also suggests that future health can continue to improve provided that innovation continues. How to finance this innovation remains an issue, but in a rich society the value of even marginal improvements in health is higher than the value of the dramatic mortality declines of the health transition.

摘要：本文讨论了健康转变理论，分析了美国的包括不同社会经地位人群中的健康分布等健康状况的转变过程。我引入了一系列广泛的健康指标：死亡率、身高、BMI(身高体重指数)，出身体重和慢性疾病。我分析了收入增长，科学技术进步以及以及它们的应用在健康转变中扮演的角色，我将证明在美国，众多的证据表明科学进步发挥了巨大的作用。我将分析在以昂贵的医疗卫生项目为主要形式的健康转变中，科学进步是如何发挥作用的。对传染病的害怕为美国政府在医疗卫生项目上花费巨大的资金提供了政治支持，即使穷人们是这些项目的最大受益者。因为最近的就科学技术进步主要集中在针对慢性疾病的治疗上，因为行为因素的重要性在不断增长，增加对穷人财政支出的政治支持可能会不断减小。我认为医疗技术进步带来生产率的提高，医疗技术的进步却不是现代经济增长的先决条件，当然，这些进步对经济发展是很重要的。当劳动形式不断的从“体力”转移到“脑力”来时，早期身体健康的效用是最大的，因为教育水平一定程度上决定薪资水平，于是健康的人不断投资于教育。尽管教育对健康的偶然影响还是不确定的，随着年龄的增长，那些受过高教育的人也许能更好的利用新的医学知识和治疗方式。因此，对健康状况的分析和理论需要把“健康”视为一个动态变量。本篇论文也预测了健康状况会随着创新的继续而不断变好。怎样去融资支持创新仍然是一个问题，但是在富裕的社会中，一个小幅度的健康水平的提高能比一个大幅度的死亡率的降低带来更高的价值。

数据来源：二手数据

研究方法：文献研究

Conclusion: This review discusses theories of the health transition and examines how the health transition occurred in the United States, including changes in the distribution of health by socioeconomic status. I bring new data to bear on an extensive array of health indicators -- mortality, height, BMI, birth weight, and chronic conditions. I investigate the role in the health transition played by rising incomes and by scientific advances and their application and I will argue that the preponderance of the evidence shows that scientific advances have played an outsize role in the United States. I will examine how these scientific advances, which during the health transition took the form of expensive sanitation projects, were implemented. Fear of infection provided the political support for the financing of these projects, even when the poor were the primary beneficiaries. Because more recent scientific advances have taken the form of therapies targeted to chronic disease and because the importance of behavioral factors has grown, political support for expenditures aimed at the poor is likely to be lower. I will argue that while improvements in health raise productivity, these improvements are not necessarily a precondition for modern economic growth. The nature of the economy in which these improvements occur also matters. The gains to early life health are largest when the economy has moved from “brawn” to “brains” because this is when the wage returns to education are high, leading the healthy to obtain more education. Although the causal effect of education on health is still unclear, those who obtain more education may be better able to take advantage of new medical knowledge and therapies as they age. Analyses and theories of health therefore need to treat health as a dynamic variable. The review also suggests that future health can continue to improve provided that innovation continues. How to finance this innovation remains an issue, but in a rich society the value of even marginal improvements in health is higher than the value of the dramatic mortality declines of the health transition.

结论：十九世纪中期到现在，美国出台了一系列的为了保障国民健康的长期措施（主要是针对疾病的科学技术进步），然而，更值得注意的从1830s到1880s期间，甚至是1990s年代出生的人群，出生体重是不断下降的。肥胖人群的增加会导致怎样的后果暂不清楚—老年肥胖已经不致命了，但是依旧会影响生活。

美国健康程度分布的变化暗示了科学进步和它们的应用的影响。在1750年左右出生的人群中，不同的社会阶层的健康不平等程度是很小的；1850年左右出生的人群的健康水平不平等程度有所加大，但依旧处于很小的范围；20世纪早期出生的人群的不平等程度增加了，但在1950年这种不平等程度达到了最低点。20世纪健康水平提高的主要受益人群主要是穷困人群。对传染病的害怕，以及债券市场的不断发展导致了对医疗健康等公共服务项目的投资大幅度增加。因为一些新知识（例如对吸烟的危险意识）的影响和医疗技术不成比例的有益于受过高等教育的人，健康不平等的程度再次扩大了。然后，如果没有对传染病的害怕，对穷苦人民的健康项目的投资意愿将会比过去更小。

健康水平的提高对生产率的影响程度比以前要更大了，这表明了经济增长中健康的重要性不断上升。因为健康和认知是相互联系的，因为经济的发展越来越取决于“智力”，即使健康水平的小幅度提升也是很有意义的。健康的提升需要依靠新的医疗技术。

长期的健康趋势对微观和宏观的健康模型都有影响。数据表明人群在变老的过程中有了自己及其父母相同的体验，且当这不能被传统理论解释时，健康的静态模型就被包含在健康的动态模型中，如Heckman (2007) 、Conti与Heckman (2010)的模型，该模型是受到医疗研究者承认的。根据长期的趋势，没有证据表明健康水平的提升会导致马尔萨斯陷阱。因为人们会通过增加人力资本来让健康资本转化成生产水平的提高，健康的提升在智力经济中对经济的增长是很有效的。

                                       （By 王米娜)