Impact of the South African Child Support Grant on memory decline and dementia probability in rural and low-income mothers, 2014-2021.

INTRODUCTION

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).

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.