Are improvements in senescent life expectancy accelerating or decelerating?

该项目的主要目标是确定近几十年来发达国家的预期寿命增长是加速还是减速。在发达国家，以出生时的传统预期寿命衡量的寿命已经增加了大约两个世纪，但改善的速度正在放缓，对未来趋势存在相当大的分歧。悲观主义者认为我们正在接近预期寿命的极限。相比之下，乐观主义者预计，由于老年人的死亡率正在迅速下降，情况将无限制地持续改善。这些关于未来的对立观点植根于对最近死亡率趋势的分歧。这项拟议中的研究将试图通过评估27个发达国家预期寿命的最新趋势来解决这一争议。具体目标是：（1）制定/确定一套老龄预期寿命趋势指标。提出了五项指标：（a）在没有非衰老死亡率的情况下的出生时预期寿命。这将被视为参考指标; B）65岁时的预期寿命; c）65岁时调整后的预期寿命; d）65岁以上死亡率的年龄变化; e）65岁以上按年龄分列的死亡率寿命表成人模式分布。2)根据这五个指标获得预期寿命老化趋势的经验估计数。所有经验估计数将来自人类死亡率数据库中1950年以后所有可用年份27个人口中女性和男性的数据。3)检验1950年以来五个指标趋势的相似性和差异的三个假设。4)估计衰老死亡年龄的变化趋势，并评估其对预期寿命的影响。 项目叙述：工业化世界人口迅速老龄化，导致越来越需要更准确地预测死亡率和老年人口规模。这项拟议中的研究审查了衰老预期寿命趋势的替代指标，以阐明关于出生时预期寿命未来趋势的持续争议。预计这一分析将导致更准确地估计预期寿命的当前趋势，从而为更准确和更有力地预测死亡率以及养恤金和保健系统的未来费用提供基础。

DESCRIPTION (provided by applicant): The project's main objective is to determine whether increases in senescent life expectancy in recent decades are accelerating or decelerating in developed countries. Longevity as measured by the conventional life expectancy at birth has risen for about two centuries in the developed world, but the pace of improvement is decelerating and there is considerable disagreement about future trends. Pessimists believe we are approaching limits to life expectancy. In contrast, optimists expect continued improvements with no limits because mortality rates at older ages are declining rapidly. These opposing views about the future are rooted in disagreement about recent trends in mortality. The proposed study will attempt to resolve this controversy by assessing recent trends in senescent life expectancy in 27 developed countries. Specific aims are: 1) Develop/identify a set of indicators of trends in senescent life expectancy. Five indicators are proposed: a) life expectancy at birth in the absence of non-senescent mortality. This will be considered the reference indicator; b) life expectancy at age 65; c) adjusted life expectancy at age 65; d) age shift in the force of mortality at ages 65+; and e) the adult mode of the life table distribution of death rates by age above age 65. 2) Obtain empirical estimates of trends in senescent life expectancy based on these five indicators. All empirical estimates will be derived from data in the Human Mortality Database for females and males in 27 populations for all available years after 1950. 3) Test three hypotheses about similarities and differences in trends in the five indicators since 1950. 4) Estimate trends in the variation in the age at senescent death and assess their impact on trends in senescent life expectancy. Project Narrative: Rapid aging of populations in the industrialized world has led to growing demand for more accurate projections of mortality and of the size of the population of elderly. The proposed research examines alternative indicators of trends in senescent life expectancy to shed light on the ongoing controversy about future trends in life expectancy at birth. This analysis is expected to result in more accurate estimates of current trends in senescent life expectancy thus providing the basis for more accurate and more robust long-range projections of mortality and of the future cost of pension and health care systems.