Genomics & Biobanks

Measuring T3 in STAR

Daniel Hochbaum & Ralph Lawton

The Study of Tsunami Aftermath and Recovery (STAR) seeks to answer questions surrounding the long-term impacts of traumatic events and natural disasters on economic outcomes, demographic outcomes, and health. The design of STAR leverages unique characteristics of the 2004 tsunami to provide plausibly-causal estimates of the ramifications of disasters and traumatic exposures. The 2004 tsunami was a massive tragedy, with waves of over 30m impacting the coastline. However, since no tsunami had occurred in over 500 years on mainland Sumatra, no warning systems were in place, nor was a tsunami expected. Exposure in the mountainous region was dependent not only on altitude but the topography of the seafloor and coastline, so the location of affected areas are effectively random. This natural experiment is key to the study design. Nearly 30,000 people that partook in a national-representative census survey earlier in 2004 were tracked, including those who migrated. Upwards of 95% of survivors have been re-interviewed and followed for the past 15+ years. As a result, the STAR study provides the opportunity to study a population-representative sample exposed to the 2004 tsunami, enabling plausibly causal interpretation of its effects. Further, STAR contains longitudinal data on economic behavior, aid given and received, and community-level infrastructure data. A new wave of the survey, a randomly-selected subsample of 4,000 respondents, is about to be fielded with further biomarker assessment. With this proposal, we will add a measure of thyroid hormone, T3, to the assessment battery. T3 is the active form of thyroid hormone. Known to be a regulator of metabolism, we have found that in addition it has profound behavioral effects in animals and humans, even evident in population-level economic behavior. 

Dysregulated thyroid signaling has been associated with PTSD. However, these studies look at clinical hypo- or hyper-thyroidism. We have shown that normal variation in T3 levels effects human exploratory and risk-taking behaviors, and socio-economic outcomes. How a traumatic event alters T3 levels directly, as opposed to a clinical diagnosis of hypo- or hyper-thyroidism, will give far richer insights into the connection between trauma and thyroid signaling. Further, STAR includes rich measures of risk-tolerance and economic behaviors, allowing us to examine how trauma may modulate the relationship of these behaviors to thyroid signaling.

Longterm impact on health of a severe economic recession during childhood and among adults

Jaakko Kaprio & Aarno Palotie

Finland suffered a very severe economic recession in the early 1990s. It was caused primarily by lax monetary policy in the 1980s combined with the ending of trade with the Soviet Union, which had been conducted on a bilateral basis. Unemployment reached almost 25% and then declined to under 10% over the next 15 years until the less severe recession in 2009/2010. Data from the Finnish Twin Cohort (FTC: 16000+ twin pairs born before 1958 and followed-up since 1975 by four surveys and nation-wide registers of health and socio-economic status) show that when GDP growth turned negative the heritability estimates based on MZ and DZ twin correlations of income (wages, capital gains and social benefits, annual data from tax authorities) decreased severely and Gini index increased (Hyytinen A et al, Heritability of Lifetime income. Helsinki Center of Economic Research, Helsinki 2013). So within twin pairs, there will be some pairs where both are roughly equally affected by the recession and others in which one twin did much better than the other. As the research team has information on the spouses and offspring of these twins from multiple registers, they are positioned to examine the long-term impact of the recession on families. This project proposes to study the effect of this recession among families of the adult twins on their health, economic well-being and criminal behavior.

Sexual Violence and Cardiovascular Disease Within and Across Generations

Rebecca Lawn

The overall objective of this project is to comprehensively test whether lifetime exposure to sexual violence (type, timing, and burden) among women is prospectively related to later risk of cardiovascular disease (CVD) within and across generations. The central hypothesis is that women’s sexual violence history (including childhood sexual abuse, adolescent sexual abuse, intimate partner violence, sexual assault, stalking, and workplace sexual harassment) will be associated with CVD, as well as CVD-related outcomes in their offspring (e.g., hypertension, diet quality). We further predict that a greater burden of exposure to sexual violence, particularly earlier in life, will be associated with a higher risk of CVD (within women) or CVD-related outcomes (among their offspring) and that relationships will be observed even after considering established behavioral and psychological risk factors, and offspring's own experiences of sexual violence. The proposed project provides a rare opportunity to elucidate the cardiovascular implications of sexual violence over the life course through leveraging the unique and already collected data of the Nurses’ Health Study II and the Growing Up Today Study. 

A further exploratory objective is to examine genetic risk for CVD-related outcomes as a potential modifier. Recent genetic risk scores have been shown to strongly predict CVD-related outcomes (e.g., coronary artery disease) however, it is not clear whether genetic effects on cardiovascular health are greater in women with a sexual violence history. We will explore whether women with both sexual violence history and high genetic liability for CVD-related outcomes are most likely to develop these diseases.

Leveraging Pediatric Cohort Data to Gain Insights into Heterogeneity in Response to Trauma

Natalie Slopen & Andrea Roberts

As the science of childhood trauma and resilience advances, there is increasing recognition that an enhanced understanding of variation, or “heterogeneity”, in responses to trauma can lead to improved and tailored interventions. The concept of heterogeneity is relevant to public health research on childhood trauma in terms of (1) the breadth of outcomes that follow from trauma, (2) characteristics that shape variation in post-trauma symptom development, and (3) types of events that constitute trauma. Although a large literature has documented associations between childhood trauma and psychopathology, the extent to which childhood trauma is related to other health outcomes in adolescence is less clear. Related, only a subset of individuals exposed to trauma develop symptoms of psychopathology, and explanations for this variation are limited. Moreover, a major methodologic challenge of child trauma research is heterogeneity in experiences that officially qualify as trauma. Certain experiences that are more common among children from minoritized racial/ethnic groups (such as racial discrimination and home evictions) are not recognized as traumas in the DSM, even though these experiences are associated with symptoms of post-traumatic stress disorder, thus potentially systematically underestimating the role of trauma in health inequities. The overarching objective of this proposal is to advance the understanding of heterogeneity in responses to childhood trauma by applying two promising epidemiologic approaches that have seldom been used within pediatric trauma research. The proposal will draw on data from the Adolescent Brain and Cognitive Development (ABCD) Study, a well-characterized and diverse ongoing cohort that our team has been working with during the past year (n=11,848 at baseline; mean 9.9 y). By the start of the project period, data on the full ABCD cohort is expected to be available for at least three years of follow-up, allowing for a robust prospective design. Repeated assessments will allow us to construct causally informed designs to assess within-person change over time, given the availability of pre-trauma characteristics, incident trauma, and repeated outcome measurements.