Socioeconomic stability plays an important role in the normal development of a child. So, it is not surprising that adverse socioeconomic conditions arising from difficult financial circumstances have been associated with a number of mental health and cognitive problems. The motivation for the current line of thinking is a recent study published in JAMA: Psychiatry wherein we noted that macroeconomic shocks such as recessions can have long-term effects on the mental and emotional health of children between the ages of 0-18 months. Over the last two years, we have been expanding our work on the concept of socioeconomic depreciation (SED) or drop in family income. In this proposal, we will examine the mechanism behind the influence of SED on future behavior problems. Specifically, we are proposing that SED will affect attachment, which in turn will affect social development. Since attachment variables are not available in the ALSPAC data, ALSPAC will not be used to develop this particular hypothesis. However, ALSPAC will be used to explore the role of social development in future behavior problems. (Figure 1 available on request).

Secondly, we propose to explore the effects of prenatal exposure to SED. Borrowing from literature on fetal programming, we propose that prenatal exposure may lead to changes in temperament and increase vulnerability to behavior problems. Temperament has been described as a stable system of traits that moderates susceptibility to behavioral and emotional problems. In line with this argument, this study will examine if temperament moderates the link between SED and behavioral and emotional problems (Figure 2 available on request).

This proposal also extends our work into SED by testing for gene by environment interactions using the large public data sets from the Psychiatric Genomics Consortium (PGC). Because Dr. Faraone is on the PGC's Coordinating Committee, this aspect of the work will be straightforward. For each disorder, the PGC computed a SNP heritability, which indexes the amount of heritability due to common SNP variants. These SNP heritabilities were all much greater than zero and were statistically significant. These analyses also showed substantial and significant correlations between the heritabilities of some of these disorders. For example the correlation between schizophrenia and each of the mood disorders was greater than 0.4. This cross disorder polygenic overlap, along with prior evidence of overlap for single SNP variants and for CNVs, has confirmed prior work from genetic epidemiology indicating shared genetic risk factors among multiple psychiatric disorders. This work is relevant to genetic studies of SED because it allows us to create molecular polygenic scores for use in testing gene by environment interaction. These scores may explain, for example, whey two children raised in identical SED circumstances have different outcomes. When added to knowledge about SED, these genetic data could help allocate scarce resources where they are most urgently needed.

For this project, we propose to use ALSPAC. Details about our proposed work with ALSPAC are discussed below. ALSPAC data will be used to test the following hypotheses. The scientific outline (Section 8) provides a list of specific variables requested, and how those variables will be used in hypothesis testing. In that table, DV refers to Dependent (or Outcome) Variable, IV to Independent (or Exposure) Variable, MV to Moderating Variable, and CV to Confounding Variable.