Department of Epidemiology and Biostatistics, Indiana University School of Public Health-Bloomington, Bloomington, IN, USA.
School of Nursing, George Washington University, Washington D.C., USA.
Soc Sci Med. 2024 Oct;358:117217. doi: 10.1016/j.socscimed.2024.117217. Epub 2024 Aug 17.
Aging populations across sub-Saharan Africa are rapidly expanding, leading to an increase in the burden of Alzheimer's disease and related dementias (ADRD). Cash transfer interventions are one plausible mechanism to combat ADRD at a population-level in low-income settings. We exploited exogenous variation in eligibility for South Africa's Child Support Grant (CSG) to estimate the longitudinal association between potential CSG benefit and cognitive trajectories in rural mothers with <10 children (n = 1090).
South Africa's CSG delivers monthly cash payments to primary caregivers, predominantly mothers, to offset the costs associated with child rearing. This study implemented a quasi-experimental design using data (2014-2022) from a rural, low-income cohort in the Agincourt research area, South Africa. We fit linear mixed effects models and generalized linear models to estimate the association of potential CSG benefit per eligible child with memory decline and dementia probability, respectively. We stratified all models by the mother's total number of children (1-4 and 5-9) and examined effect modification by household wealth and the mother's education level.
Having above median CSG per eligible child was associated with higher baseline memory scores (β = 0.12 SD units, 95% CI = 0.02, 0.22) but steeper memory decline (β = -0.02 SD units, 95% CI = -0.04, -0.00) compared to below median CSG. Within stratified analyses, this effect was primarily observed among mothers with 5-9 children. No associations were observed between potential CSG per eligible child and dementia probability.
Our findings support the use of large-scale cash transfers as a promising intervention to promote healthy cognitive aging in mid-life women within rural, low-income settings. However, we found evidence that the CSG in its current structure may not be sufficient support for women to sustain measurable cognitive benefits over the long-term.
撒哈拉以南非洲地区的人口老龄化正在迅速扩大，导致阿尔茨海默病和相关痴呆症（ADRD）的负担增加。现金转移干预措施是在低收入环境中针对人群一级预防 ADRD 的一种可行机制。我们利用南非儿童抚养补助金（CSG）资格的外生变化，来估计潜在 CSG 收益与农村母亲（<10 个孩子，n=1090）认知轨迹之间的纵向关联。
南非的 CSG 向主要是母亲的主要照顾者每月发放现金，以抵消抚养孩子的相关费用。本研究使用南非 Agincourt 研究地区农村低收入队列的数据（2014-2022 年）实施了准实验设计。我们使用线性混合效应模型和广义线性模型，分别估计了每个符合条件的孩子的潜在 CSG 收益与记忆下降和痴呆症概率之间的关联。我们按母亲的孩子总数（1-4 个和 5-9 个）对所有模型进行分层，并检查了家庭财富和母亲教育水平的效应修饰作用。
每个符合条件的孩子的 CSG 中位数以上与较高的基线记忆分数相关（β=0.12 标准差单位，95%CI=0.02，0.22），但与记忆下降较快相关（β=-0.02 标准差单位，95%CI=-0.04，-0.00）相比 CSG 中位数以下。在分层分析中，这种影响主要出现在有 5-9 个孩子的母亲中。没有发现潜在 CSG 与痴呆症概率之间存在关联。
我们的研究结果支持将大规模现金转移作为一种有前途的干预措施，以促进农村低收入环境中中年女性的健康认知衰老。然而，我们发现，目前的 CSG 结构可能不足以支持女性在长期内维持可衡量的认知收益。
