July 13, 2023 – Ryan Keen, a Harvard Horizons Scholar, graduated with a PhD in population health sciences this May. He was the lead author of a recent study in JAMA Pediatrics that explored the relationship between childhood housing insecurity and mental health.
Q: Your study created and used a broader definition of housing insecurity than most prior studies. Why?
A: Despite there being a fair amount of research on child health and housing, the U.S. doesn’t actually have a standard definition of housing insecurity. Many of the definitions used in research studies could be considered incomplete because they capture one aspect of housing insecurity while omitting others. At the same time, it’s also unclear whether housing insecurity represents its own unique adverse childhood experience or if it’s primarily a manifestation of family income poverty.
We chose to focus on four measures that we believed more completely captured the interrelated facets of childhood housing insecurity: frequent residential moves; reduced standards of living; involuntary separation of the child from their home; and foster care status. Using these measures for our study’s definition of childhood housing insecurity made it more comprehensive and provided us opportunities to assess unique combinations of these facets and examine them independently. So, if one of the facets had a much larger impact on mental health than the others, we would have found that; if two of them combined had an outsize impact on anxiety and depression, we would have found that, as well. This approach also allows readers to consider alternative definitions of childhood housing insecurity if they disagree with our main definition. And, importantly, none of these facets relied on reports of family income poverty. In fact, many participants in the study who had experienced childhood housing insecurity never reported living below the poverty line as children.
We were able to work with the Great Smoky Mountains Study, an ongoing cohort study of individuals in western North Carolina that began in the early 90s. Children were either age 9, 11, or 13 when they started and are still being assessed as adults today. Impressively, in its early stages, the study managed to retain between 90% and 95% of participants with equally high response rates across nearly all questions. Even today, around 80% of the participants remain. Because of its longevity and comprehensiveness, the study provided us with a truly remarkable data set, comprised of repeated assessments of childhood housing insecurity, anxiety, depression, and many potential confounders.
Q: What did the study find?
A: We combined several modeling methods to look at the relationship between housing insecurity and mental health. And, in doing so, we found strong evidence that childhood housing insecurity was associated with higher anxiety and depression symptom scores during childhood and higher depression symptom scores during adulthood. Generally speaking, these results suggest that children who experienced housing insecurity are more likely to develop anxiety and depression symptoms during childhood and adolescence and more likely to develop depression symptoms as adults than housing-secure children.
These associations held after adjusting for many potential confounders. Poverty was, perhaps, the most noteworthy factor we adjusted for; when we did so, the associations between housing insecurity and mental health remained virtually unchanged. In fact, the associations between poverty and anxiety and depression were much smaller in magnitude than those of housing insecurity. Of course, poverty and housing insecurity share a number of attributes and are often co-occurring. However, the results suggest that housing insecurity has its own impact on child mental health that is distinct from that of poverty, some of which we see lasts into adulthood. I think this may be because housing insecurity is a bit more palpable to children than falling above or below a somewhat arbitrary poverty threshold.
One of the most fascinating things about the study is that results were pretty much consistent regardless of how we defined childhood housing insecurity. Essentially, all four of the measures had a similar impact on anxiety and depression. That made us a lot more confident about our broad definition of childhood housing insecurity.
Q: What are the public health takeaways of your research?
A: First, we must move towards a more unified definition of childhood housing insecurity. All of the facets of childhood housing insecurity that we assessed contributed to poor mental health outcomes—so we really have to start considering them all, independently and jointly, in order to better identify children in need of support and design more effective interventions and policies. Second, we must improve collaboration across sectors—across policymakers, researchers, physicians, social workers, and community-based organizations—to better integrate and optimize the resources and support systems that are available. Third, we have to invest in primary data collection efforts in order to change the fact that there are so few data sets in the U.S. that we can rely on to look at the short- and long-term effects of childhood housing insecurity and homelessness. Without these data, we are limited in our ability to advance the evidence-base and interdisciplinary expertise that we need to design more innovative, comprehensive interventions and policies.
As for future research, The Great Smoky Mountains Study collected many biomarkers among participants. As someone who studied biochemistry prior to population health, the next question I’m most interested in is: How might housing insecurity ‘get under the skin’ and become biologically embedded to impact health and development over the life course? If childhood housing insecurity and homelessness do, in fact, have direct, underlying biological consequences, do they also meet the criteria to be considered chronic diseases? Could—should—we reframe them that way?