Cumulative socioeconomic exposures, cash transfer interventions, and later-life cognitive decline and dementia risk in a low-income region of South Africa

项目总结 到2050年，75%的阿尔茨海默病和相关痴呆(ADRD)病例将发生在中低收入人群中 像南非农村这样的地区，在ADRD研究中的代表性严重不足。有一个关键的问题 关于社会经济地位(SES)在低收入环境下ADRD病因学中的作用的证据差距，以及SES如何 最有针对性的干预措施可以预防和/或推迟ADRD的发病。我们的长期目标是让 设计性别平等的社会经济干预措施，以预防和/或推迟低收入环境中的ADRD发病。这个 这项建议的目标是确定使用纵向暴露(家庭)，SES如何影响ADRD风险 资产、粮食安全和就业)以及随机化和准随机化现金转移风险 随着时间的推移，在南非农村生活的中后期积累起来。我们的中心假设是，更大的累积 暴露在有利的社会经济条件下将预防ADRD，对男性有不同的影响 妇女获得家庭一级的社会经济地位资源，这些资源可能在两性之间不平等地分配。为了测试这一点 中心假设，我们将利用一个独特的机会创建首批纵向数据平台之一 研究ADRD在非洲的风险：我们将把2015-21年间收集的高质量记忆和ADRD结果数据联系起来 具有人口代表性的《非洲的健康和老龄化：对INDEPTH社区的纵向研究》 南非“(HAALSI；N=5059)至2000年以来在《阿金库尔健康》中收集的详细的SES暴露数据 和社会人口监测系统(AHDSS；100%人口覆盖率的人口普查)和HPTN 2011年至2015年向家庭转移现金的068个随机对照试验(N=863个家庭在两个HPTN 068和HAALSI)。这三个数据集可以链接，因为AHDSS人口普查是 HAALSI和HPTN 068；我们在初步数据中确认了连锁的可行性。具体地说，我们的目标是：1) 确定中老年累积家庭资产、就业和粮食安全的作用(2000-13年； AHDSS)记忆力下降和ADRD风险(2015-21；HAALSI)；2)确定是否暴露于现金转移 干预措施通过利用2a)HPTN 068中的随机现金转移影响记忆力下降和ADRD；2b) 扩大南非男子老年养恤金；2c)扩大南非子女抚养金 对于母亲；以及3)确定性别如何改变AIMS 1&中家庭一级SES暴露的影响 2A。这项建议是创新的，因为南非农村老年黑人成年人的研究人群改善了 ADRD研究中研究不足群体的代表性；我们对SES暴露的纵向评估 14年来，回顾或在单个时间点衡量的SES现状有所改善；我们的 HAALSI队列与随机对照现金转移试验和国家社会保护数据的联系 政策允许对收入和ADRD风险进行因果推断。这项提议是人生历程中的一个重大机遇 对快速老龄化的低收入人群进行的研究，可以为ADRD的病因和策略提供见解 预防和/或推迟ADRD在全球低收入环境中的发病，因为除了这项研究之外，这些环境中几乎没有数据。

PROJECT SUMMARY By 2050, 75% of Alzheimer’s disease and related dementias (ADRD) cases will occur in low- and middle-income regions, like rural South Africa, which are severely under-represented in ADRD research. There is a critical evidence gap on the role of socioeconomic status (SES) in ADRD etiology in low-income settings, and how SES can best be targeted by interventions to prevent and/or delay ADRD onset. Our long-term goal is to inform the design of gender-equitable SES interventions to prevent and/or delay ADRD onset in low-income settings. The objective of this proposal is to identify how SES affects ADRD risk, using longitudinal exposures (household assets, food security, and employment) and randomized and quasi-randomized cash transfer exposures accumulated over time in mid-to-later-life in rural South Africa. Our central hypothesis is that greater cumulative exposure to advantageous socioeconomic conditions will protect against ADRD, with differential effects for men and women for household-level SES resources that may not be equally allocated between genders. To test this central hypothesis, we will leverage a unique opportunity to create one of the first longitudinal data platforms to study ADRD risk in Africa: we will link high-quality memory and ADRD outcome data collected from 2015-21 in the population-representative “Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa” (HAALSI; N=5059) to detailed SES exposure data collected since 2000 in the “Agincourt Health and Sociodemographic Surveillance System” (AHDSS; a census with 100% population coverage) and the HPTN 068 randomized controlled trial of cash transfers to households from 2011-15 (N=863 households in both HPTN 068 and HAALSI). These three datasets can be linked because the AHDSS census is the sampling frame for HAALSI and HPTN 068; we have confirmed linkage feasibility in our preliminary data. Specifically, we aim to: 1) Determine the roles of mid-to-later life cumulative household assets, employment, and food security (2000-13; AHDSS) in memory decline and ADRD risk (2015-21; HAALSI); 2) Determine whether exposure to cash transfer interventions affect memory decline and ADRD by leveraging 2a) randomized cash transfers in HPTN 068; 2b) expansion of the South African Old Age Pension for men; 2c) expansion of the South African Child Support Grant for mothers; and 3) Determine how gender modifies the effects of household-level SES exposures in Aims 1 & 2a. This proposal is innovative because the study population of older, rural Black South African adults improves representation of understudied groups in ADRD research; our longitudinal assessments of SES exposures over 14 years improve upon the status quo of SES measured retrospectively or at single points in time; and our linkage of the HAALSI cohort to a randomized controlled cash transfer trial and data on national social protection policies allows causal inference about income and ADRD risk. This proposal is a major opportunity for life course research in a rapidly aging, low-income population that can provide insights into ADRD etiology and strategies to prevent and/or delay ADRD onset in global low-income settings, where there is little data outside this study.