Adverse early life conditions can have consequential impacts on individuals' health in older age. In one of the first papers on this topic,  show a strong positive relationship between infant mortality rates in the 1920s and ischemic heart disease in the 1970s. We go beyond Barker, first by showing that this relationship is robust to the inclusion of local geographic area fixed effects, but not family fixed effects. Second, we report considerable genetic heterogeneity that is robust to within-area as well as within-family analyses. Our findings show that infant mortality rates mainly affect individuals with the highest genetic risk for developing heart disease. Put differently, in areas with the lowest infant mortality rates, the effect of one's genetic predisposition effectively vanishes. These findings suggests that advantageous environments can cushion one's genetic disease risk.
Samuel Baker, University of Bristol
Pietro Biroli, University of Bologna
Hans van Kippersluis, Erasmus University Rotterdam
Stephanie von Hinke, University of Bristol; Erasmus University Rotterdam