UK-China Health And Social Challenges Ageing Project: present and future burden of dementia, and policy responses

中国有1040万痴呆症病例，这个数字还将上升。与英国和其他国家相比，中国的快速老龄化进程发生在经济发展的早期阶段，对医疗和护理服务提出了巨大的需求。针对这一情况的政策制定将受益于对中国老年人口疾病负担、相关保健和社会护理费用以及未来预防心血管疾病、痴呆症和残疾的前景等方面的流行病学和经济学的权威预测，直至2050年。英国和中国的65岁以上人口分别为1270万和1.73亿。对不同国家的卫生和社会保健政策进行深入的比较，将对政策制定者具有科学的启发性和价值。我们建议基于最近为英国开发的模拟模型（BMJ 2017，Lancet Public Health 2017），为中国人口建立一个模拟模型，以直接比较2050年的主要统计数据和指标。该模型综合了主要观察到的流行病学和人口趋势，以预测痴呆症，残疾和心血管疾病的疾病负担，以及未来三十年的预期寿命（总预期寿命（LE），残疾LE和无残疾LE）。痴呆症未来负担的一个关键决定因素是其发病率趋势。我们对中国纵向健康长寿研究（CLHLS）的纵向分析显示，在考虑非随机脱落和竞争风险后，1998-2014年期间，年龄调整的痴呆发病率每年下降2.8%。疾病发生率的快速变化，加上中国人口老龄化，意味着目前的预测可能不准确。内置情景建模功能，允许用户模拟健康干预措施和风险因素（如吸烟和肥胖）的社会趋势对痴呆症和其他年龄相关结果的影响（Diabetologia 2019）。我们的方法是使用CLHLS和中国健康与退休纵向研究健康（CHARLS）中的认知和身体功能的重复测量来识别符合DSM 4的痴呆病例。我们计划使用临床神经心理学家访谈作为参考点进行验证研究。对于模型的社会经济功能，健康和社会保健成本，包括与生育相关的间接成本，将利用WHO-SAGE-China以及CLHLS和CHARLS数据。该项目将使用模拟预测来检查预计的抚养负担与政策反应，特别是长期护理之间的匹配性。这一目标涉及两国经验丰富的政策分析人员采用的混合方法。第一步是对中国目前长期培训试点项目的政策制定过程进行定性分析。第二，政策分析员和模拟小组将沿着对相对经济成本的评估，对所述政策意图和试点项目可能满足预计需求的程度进行定量评估。我们计划一个“换位”的方法（森1993年），同时考虑内部的观点（CN系统的CN研究者）和外部的观点（CN系统的英国研究者），从而明确的文化（或位置）观察的依赖性。对不同的“位置”观察进行整理，可以得到有用的理解，而不是通过其他方式获得。我们的跨学科团队将由来自UCL和中山大学（SYSU）的流行病学家领导，以及经济学家（UCL/中山大学财政研究所，广州医科大学（GZMU）），统计学家和数学家（SYSU），神经心理学家（GZMU），临床医生（GZMU，UCL），政策分析师（Nuffield Trust，SYSU）等。该研究将在中国，英国和国际上做出重大的科学和政策相关贡献，超越三年项目。

There are 10.4M cases of dementia in China, and this number will rise. China's rapid ageing process is occurring at an earlier stage of economic development than UK and other countries, posing great demands on health and care services. Policy development in response to this situation would benefit from authoritative forecasts, to 2050, of the epidemiology and economics of China's older population in respect of disease burden, related costs of health and social care, and prospects for future prevention of cardiovascular disease, dementia and disability. The 65+ population of UK and China is 12.7 M and 173 M respectively. Thoughtful comparison of health and social care policy across the contrasting countries will be scientifically illuminating and valuable to policy makers. We propose to build a simulation model for the Chinese population, based on that recently developed for UK (BMJ 2017, Lancet Public Health 2017), for direct comparison of headline statistics and indicators to 2050. The model synthesises the major observed epidemiological and demographic trends, in order to forecast disease burden for dementia, disability and cardiovascular disease, and life expectancy (total life expectancy (LE), disabled LE, and disability-free LE) for the next three decades. A key determinant of the future burden of dementia is its incidence trend. Our longitudinal analysis of the Chinese Longitudinal Healthy Longevity Study (CLHLS) shows age-adjusted dementia incidence declined 2.8% per year in the period 1998-2014, after accounting for non-random dropout and competing risks. Such rapid changes in disease occurrence, together with China's ageing demographic, mean that current forecasts are likely to be inaccurate. Scenario-modelling functions are built in to allow the user to simulate the impacts of health interventions and social trends in risk factors, such as smoking and obesity, on dementia and other age-related outcomes (Diabetologia 2019). The robustness of modelled estimates is tested with sensitivity analysis.Our approach is to use repeat measures of cognitive and physical function in CLHLS and the China Health and Retirement Longitudinal Study Health (CHARLS) to identify DSM4-compliant dementia cases. We plan a validation study using a clinical neuropsychologist interview as point of reference. For the socioeconomic function of the model, health and social care costs, including indirect costs associated with caregiving, will draw on WHO-SAGE-China as well as CLHLS and CHARLS data. The project will use the modelled forecasts to examine the fit between projected dependency burden and policy responses, particularly Long-Term Care (LTC). This objective involves mixed methods, carried out by experienced policy analysts in both countries. The first step will be qualitative analysis of the policy development process for the current LTC pilot projects in China. Second, quantitative evaluation of the extent to which the stated policy intentions, and pilot projects, are likely to meet projected needs, will be conducted jointly by policy analysts and modelling teams along with assessment of relative economic costs. We plan a 'trans-positional' approach (Sen 1993), to consider both the internal view (CN researcher of CN system) and external view (UK researcher of CN system) thereby making explicit the cultural (or positional) dependence of observation. Reconciling divergent 'positional' observations leads to useful understanding, not otherwise achieved. Our interdisciplinary team will be led by epidemiologists from UCL and Sun Yat-Sen University (SYSU) together with economists (UCL/Institute for Fiscal Studies, SYSU, Guangzhou Medical University (GZMU)), statisticians and mathematician (SYSU), neuropsychologists (GZMU), clinicians (GZMU, UCL), policy analysts (Nuffield Trust, SYSU) and others. The study will make significant scientific and policy-relevant contributions in China, UK and internationally, beyond the three-year project.