Determinants and trajectories of healthy life expectancy and deficit accumulation in older adults in Germany - follow-up of the KORA-Age cohort study

预期寿命的延长加上出生率的放缓，如果这增加了慢性病患者在人口中较长时间生存的比例，将对组织和财政构成挑战。关于发病率压缩或扩展的经验证据仍然是矛盾的。健康预期寿命（HLE）在各国之间差异很大，德国低于欧洲平均水平。在这里，性别、年龄层和出生队列的估计是模糊的。健康预期寿命的异质性可能是由于关键（战前、战后）寿命期的影响，也可能是由于寿命期间功能状态的逐渐恶化，即缺陷积累（DA）。因此，我们建议在德国老年人口的代表性样本中研究HLE的决定因素，将早期生活经历作为出生队列和DA的结果考虑在内。我们计划使用完善的奥格斯堡地区合作卫生研究（KORA）平台进行新的数据收集，并使用我们现有的KORA-年龄队列数据。我们计划在KORA年龄队列中检验HLE和DA作为出生队列和性别的函数，并检验DA与死亡率的关系。自1984年以来，在德国奥格斯堡和周边两个县进行了四项基于人口的横断面研究，即koa调查S1至S4。年龄组别包括所有在2008年底年龄在65岁或以上，即在1943年或以前出生的受访者。KORA-Age的基线研究于2009年进行。拟议的队列研究将作为一项为期7年的重新评估，对大约2500名kora -年龄基线研究的参与者进行评估。2015/2016年，参与者年龄为73 - 96岁（老年亚组，第一阶层）。此外，在2008年底还未满65岁，因此不符合KORA年龄基线，但在2015年底将达到65至72岁的年轻参与者将被纳入所有KORA S1-S4参与者的年龄和性别分层样本（即出生于1944年至1950年的年轻亚组，第II层）。所有信息将通过邮政卫生后续调查获得，其中包括一份简短的健康调查表和电话访谈。预期健康将被定义为在不同健康状态下度过的时间，直到死亡。作为DA的总结性衡量标准，赤字积累指数（DAI）将按照明确的程序构建。DAI将包含体征和症状、疾病、功能障碍和活动限制。将对数据拟合多变量对数线性、混合效应和Cox回归模型。包括广泛的出生队列和纵向随访，应该可以解开导致发病率压缩或延长的机制，分离年龄，时期和队列效应。

Increasing life expectancy combined with slowing birth rates will be an organizational and financial challenge if this increases the share of persons in the population living longer periods of time with chronic disease. Empirical evidence regarding the compression or extension of morbidity is still ambivalent. Healthy life expectancy (HLE) varies largely across countries, with Germany being below the European average. Here, estimates are ambiguous across gender and age strata and birth cohorts. Heterogeneity in healthy life expectancy can be due to the influence of critical (pre-, peri-post-war) life periods or to the gradual deterioration of functional status over the life span, i.e. deficit accumulation (DA). We therefore propose to study determinants of HLE in a representative sample of the aged German population, taking early life experience as a consequence of birth cohort and DA into account. We plan to use the well-established KORA (Cooperative Health Research in the Region of Augsburg) platform for a new data collection, and to use our already existing data from the KORA-Age cohort. We plan to examine HLE and DA as a function of birth cohort and sex in the KORA Age cohort, and to examine the association of DA with mortality. Since 1984 four cross-sectional population based studies, the KORA surveys S1 to S4, were conducted in Augsburg, Germany, and two surrounding counties. The KORA-Age cohort includes all participants from those KORA surveys aged 65 years or older at the end of 2008, i.e. born in or before 1943. The baseline study of KORA-Age took place in 2009. The proposed cohort study will be carried out as a 7-year re-assessment of estimated 2500 participants of the KORA-Age baseline study. Participants will be aged 73 to 96 years in 2015/2016 (older subgroup, stratum I). Additionally, the younger participants from the KORA surveys who were not yet 65 at the end of 2008 and thus not eligible for KORA-Age baseline but will be 65 to 72 at the end of 2015 will be included as an age- and sex-stratified sample of all KORA S1-S4 participants (i.e. born from 1944 to 1950, younger subgroup, stratum II). All information will be obtained by means of a postal health follow-up with a short health questionnaire and a telephone interview. Health expectancy will be defined as the time spent in different health states until death. As summary measure for DA, a Deficit Accumulation Index (DAI) will be constructed according to a well-defined procedure. The DAI will contain signs and symptoms, diseases, functional impairments and activity restrictions. Multivariable log-linear, mixed-effects and Cox regression models will be fitted to the data. Including a wide span of birth cohorts with longitudinal follow-ups should make it possible to disentangle the mechanisms that lead to a compression or extension of morbidity, separating age, period, and cohort effects.