# SES health gradients in late life: testing models of gene-environment interplay in an international twin consortium

> **NIH NIH R01** · UNIVERSITY OF SOUTHERN CALIFORNIA · 2020 · $555,366

## Abstract

Inequalities in health outcomes are targeted by Healthy People 2020 as a public health priority. The social
stratification of health is well documented, pervasive, and of growing concern because it appears to be
increasing over time. Reducing these social class disparities will require greater understanding of how social
class impacts health than we currently have. While most research focuses on individual-level socioeconomic
status—defined as social status that accrues to occupational classification, education, and income—new
research has begun to focus on the macro-economic environment. Further, although both genetic (G) and
environmental (E) factors are known to contribute to the SES-health gradient, the mechanisms by which the
two sets of factors combine to influence health outcomes (i.e., GE interplay) are poorly understood. Models of
GE interplay differ in their environmental focus (disease-triggering effects of toxic environments vs. health-
promoting benefits of favorable environments) and the expected genetic contribution to disease (maximized in
adverse environments, in favorable environments, or at both extremes) Understanding whether high-SES
preferentially promotes good health among a genetically selected subset of individuals (i.e., social
enhancement), whether low-SES triggers poor health among a genetically vulnerable subset of individuals (i.e.,
diathesis-stress), or both, is essential for translating research in this area into effective prevention strategies.
The consortium on Interplay of Genes and Environments across Multiple Studies (IGEMS) with 16 existing
longitudinal twin studies in the U.S., Sweden, Denmark, Finland, and Australia is poised to evaluate these
models. IGEMS includes more than 52,000 individual twins, with over 7000 identical twin pairs for within-pair
difference models, and over 12,600 dizygotic twin pairs with nearly 4000 opposite sex pairs for sex-difference
models. The sample spans a wide age range (15 to 103 years at intake) and includes a set of well-characterized
longitudinal phenotypes, including harmonized measures of physical health (e.g., subjective health, chronic
disease indicators, body mass index, lung function, blood pressure, activities of daily living, and grip strength),
cognitive health (verbal ability, spatial ability, memory, and processing speed), and emotional health
(depression, loneliness) as well as measures of multiple facets of SES (e.g., occupation, education, financial
strain). In addition, a large subset of IGEMS participants has genome wide genotyping from which we have
computed polygenic risk scores (PRS). We will use co-twin control/within pair models, quantitative genetic
moderation, sex-limitation models, and PRS analyses to investigate specific mechanisms of the SES-health
gradient at the individual level as well as the country and historical cohort level (e.g., country-level indices of
social inequality). The proposed study reflects an innovative vision by the investiga...

## Key facts

- **NIH application ID:** 9953943
- **Project number:** 5R01AG059329-03
- **Recipient organization:** UNIVERSITY OF SOUTHERN CALIFORNIA
- **Principal Investigator:** Brian K. Finch
- **Activity code:** R01 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $555,366
- **Award type:** 5
- **Project period:** 2018-09-01 → 2023-05-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/9953943

## Citation

> US National Institutes of Health, RePORTER application 9953943, SES health gradients in late life: testing models of gene-environment interplay in an international twin consortium (5R01AG059329-03). Retrieved via AI Analytics 2026-05-23 from https://api.ai-analytics.org/grant/nih/9953943. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*