The Contribution of Obesity to International Differences in Longevity

描述(由申请人提供)：这项研究的主要目标是确定肥胖对国际寿命差异的贡献。美国成年人的肥胖率高于欧洲、北美或东亚的任何其他国家。与此同时，美国的预期寿命已经低于大多数其他经合组织国家，2008年在世界上排名第32位。美国在健康和长寿方面的劣势的主要原因之一是它的高肥胖率。评估肥胖对国际寿命差异的贡献的一个关键因素是与不同水平的肥胖相关的一组个人水平的死亡风险。该项目将确定与肥胖相关的一组死亡风险，这些风险应用于国际和跨期比较。为此，我们明确引入了与当前肥胖相关的死亡风险所依赖的另外两个因素：一个人的肥胖史和他或她的吸烟状况。早期研究中对肥胖史的忽略导致了对当前肥胖影响的有偏见的估计。非吸烟者比吸烟者表现出更高的肥胖死亡风险，因此吸烟严重的国家患肥胖症的风险应该更低。我们将利用这些肥胖风险来计算人口归因风险以及肥胖对生存和寿命的影响。我们工作的一个重要成果将是解释已经观察到的肥胖对死亡率的估计影响的大幅下降。此外，我们将开发一种新的间接方法，通过建立以前开发的估计吸烟可归因性死亡率的方法，来估计肥胖对国际寿命差异的贡献。对肥胖的流行病学和人口学研究将极大地受益于澄清与肥胖相关的死亡风险。这样的澄清还将有助于改善美国和其他地区的死亡率预测。对未来死亡率的不确定性是社会保障信托基金的财政收支平衡最敏感的单一因素。该项目通过将肥胖史明确地纳入风险分析而加强了对改进预测的贡献，因为这些病史在实际死亡情况之前就被揭示了。

DESCRIPTION (provided by applicant): The primary objective of this research is to identify the contribution of obesity to international differences in longevity. Adults in the United States have a higher prevalence of obesity than adults in any other country in Europe, North America, or East Asia. At the same time, life expectancy in the United States has fallen below that of most other OECD countries and ranked 32nd in the world in 2008. One of the prime candidates to account for the US disadvantage in health and longevity is its high level of obesity. A key input to evaluating the contribution of obesity to international differences in longevity is the set of individual-level mortality risks associated with different levels of obesity. This project will identify the set of mortality risks associated with obesity that should be used in international and intertemporal comparisons. We do so by explicitly introducing two other factors on which the mortality risks associated with current obesity depend: an individual's history of obesity and his or her smoking status. The omission of obesity histories from earlier studies has led to biased estimates of the effects of current obesity. Non-smokers show a higher mortality risk from obesity than smokers, so that countries that smoke heavily should be expected to have lower risks from obesity. We will apply these sets of obesity risks to calculate population attributable risks and obesity's implications for survivorship and longevity. An important product of our work will be an explanation of the large declines that have been observed in the estimated effect of obesity on mortality. In addition, we will develop a new indirect approach to estimating the contribution of obesity to international differences in longevity by building on previous methods developed to estimate smoking-attributable mortality. Epidemiologic and demographic studies of obesity would benefit greatly from a clarification of the mortality risks associated with obesity. Such a clarification would also contribute to improved projections of mortality in the US and elsewhere. Uncertainty about future of mortality is the single factor to which fiscal balances in the Social Security Trust Fund are most sensitive. The contribution of this project to improved projections is enhanced by its explicit incorporation of obesity histories into the risk analysis, since these histories are revealed well in advance of actual mortality conditions.