Preprint · Jun 30, 2026
The effect of unconditional cash transfers on epigenetic indices of biological aging and cognition across early childhood
By Sperber JF, Willems YE, Mitchell C et al.
Children growing up in conditions of socioeconomic disadvantage tend to show epigenetic (DNA methylation) differences compared to more affluent children that, in adults, are associated with accelerated biological aging, lower cognitive performance, and adverse health outcomes. Epigenetic markers of accelerated aging during early childhood may be prospective indicators of the impact of early environments on lifelong risk for aging-related disease and well-being. The Baby’s First Years study recently tested whether unconditional cash transfers to low-income families across the first four years of life caused differences in epigenetic indices of biological aging (DunedinPACE, GrimAgeAccel) and cognition (Epigenetic-g) in children at Age 4. The present study will extend this work to the Age 6 timepoint, asking whether treatment effects are detectable after two additional years of cash gifts and whether the cash gifts shapes change in epigenetic indices across early childhood. We will pursue five aims. First, we will (1) describe stability and change in DunedinPACE, Epigenetic-g, and GrimAgeAccel from Age 4 to Age 6, by estimating test-retest correlations, differences in means, and differences in variances. Next, we will (2) examine whether a family’s receipt of monthly, unconditional cash transfers across the first six years of children’s lives cause differences in children’s epigenetic indices at Age 6. We will then examine (3) if within-child changes in epigenetic indices from Age 4 to Age 6 differ between treatment and control groups and (4) if the consistency of individual differences in epigenetic indices from Age 4 to Age 6 differ between treatment and control groups. Finally, we will (5) examine if epigenetic indices are associated with developmental outcomes, and if these associations depend on treatment condition. The present document extends our previous clinical trial preregistration (identifier NCT03593356) to provide a detailed preprocessing pipeline and analysis plan for child DNA methylation data from the Age-6 timepoint.