Duncan GE

Epigenome-wide association study of physical activity and physiological parameters in discordant monozygotic twins

Duncan GE, Avery A, Thorson JLM, Nilsson EE, Beck D, Skinner MK. An epigenome-wide association study (EWAS) was performed on buccal cells from monozygotic-twins (MZ) reared together as children, but who live apart as adults. Cohorts of twin pairs were used to investigate associations between neighborhood walkability and objectively measured physical activity (PA) levels. Due […]

Cross-sectional associations between neighbourhood walkability and objective physical activity levels in identical twins

Duncan GE, Avery AR, Hurvitz P, Vernez-Moudon A, Tsang S Objectives  Physical activity is a cornerstone of chronic disease prevention and treatment, yet most US adults do not perform levels recommended for health. The neighborhood–built environment (BE) may support or hinder physical activity levels. This study investigated whether identical twins who reside in more walkable […]

Measuring and modelling perceptions of the built environment for epidemiological research using crowd-sourcing and image-based deep learning models

Larkin A, Krishna A, Chen L, Amram O, Avery AR, Duncan GE, Hystad P. Background Perceptions of the built environment, such as nature quality, beauty, relaxation, and safety, may be key factors linking the built environment to human health. However, few studies have examined these types of perceptions due to the difficulty in quantifying them […]

Bring Your Own Location Data: Use of Google Smartphone Location History Data for Environmental Health Research

Hystad P, Amram O, Oje F, Larkin A, Boakye K, Avery A, Gebremedhin A, Duncan G. Background Environmental exposures are commonly estimated using spatial methods, with most epidemiological studies relying on home addresses. Passively collected smartphone location data, like Google Location History (GLH) data, may present an opportunity to integrate existing long-term time-activity data. Objectives […]

Positive lifestyle behaviours and emotional health factors are associated with low back pain resilience

Roberts KE, Beckenkamp PR, Ferreira ML, Duncan GE, Calais-Ferreira L, Gatt JM, Ferreira P. Purpose To evaluate the relationship between lifestyle behaviours, emotional health factors, and low back pain (LBP) resilience. Methods This retrospective longitudinal study utilised 1,065 twins with a recent history of LBP from the Washington State Twin Registry. A lifestyle behaviour score […]

Changing genetic architecture of body mass index from infancy to early adulthood: an individual based pooled analysis of 25 twin cohorts

Silventoinen K, Li W, Jelenkovic A, Sund R, Yokoyama Y, Aaltonen S, Piirtola M, Sugawara M, Tanaka M, Matsumoto S, Baker LA, Tuvblad C, Tynelius P, Rasmussen F, Craig JM, Saffery R, Willemsen G, Bartels M, van Beijsterveldt CEM, Martin NG, Medland SE, Montgomery GW, Lichtenstein P, Krueger RF, McGue M, Pahlen S, Christensen K, […]

The pillars of health: influence of multiple lifestyle behaviors on body mass index and depressive symptoms in adult twins

Duncan GE, Avery AR, Tsang S, Watson NF, Williams BD, Turkheimer E. Background Guidelines promoting healthy lifestyles are cornerstones of chronic disease prevention and treatment. The purpose of this study is to investigate independent and joint associations of five key health behaviors with health outcomes (body mass index (BMI kg/m2) and depressive symptoms) in adult […]

Do married and/or cohabiting individuals fare better during the COVID-19 pandemic? Satisfaction with life and depression among adult twins in the United States

Tsang S, Avery AR, Duncan GE Due to social distancing measures implemented to mitigate the COVID-19 pandemic, individuals are spending more time isolated at home with limited physical social interactions. The current study investigated whether marriage and/or cohabitation is associated with satisfaction with life and depression among 732 adult same-sex twin pairs (monozygotic and dizygotic) […]

Changes in physical activity levels and mental health during COVID-19: Prospective findings among adult twin pairs

Duncan GE, Avery AR, Tsang S, Williams BD, Seto E. Background Physical distancing and other COVID-19 pandemic mitigation strategies have negatively impacted physical activity (PA) levels and mental health in cross-sectional studies. The purpose of this study was to investigate associations between changes in PA and mental health outcomes during the COVID-19 pandemic, following implementation […]

Differences in Stress and Anxiety Among Women With and Without Children in the Household During the Early Months of the COVID-19 Pandemic

Avery AR, Tsang S, Seto EYW, Duncan GE The COVID-19 pandemic and resulting lockdowns have had a disproportionate impact on parents of children under 18, particularly women. Mandatory school closures and loss of childcare resulted in parents balancing work, teaching, and childcare needs. A number of studies have examined changes in mental health of parents, […]

Educational attainment of same-sex and opposite-sex dizygotic twins: An individual-level pooled study of 19 twin cohorts

Silventoinen K, Bogl LH, Jelenkovic A, et al. Comparing twins from same- and opposite-sex pairs can provide information on potential sex differences in a variety of outcomes, including socioeconomic-related outcomes such as educational attainment. It has been suggested that this design can be applied to examine the putative role of intrauterine exposure to testosterone for […]

GPS-based built environment measures associated with adult physical activity

Boakye KA, Amram O, Schuna JM, Duncan GE, Hystad P. Studies often rely on home locations to access built environment (BE) influences on physical activity (PA). We use GPS and accelerometer data collected for 288 individuals over a two-week period to examine eight GPS-derived BE characteristics and moderate-to-vigorous PA (MVPA) and light-to-moderate-vigorous PA (LMVPA). NDVI, […]

Measurement of neighborhood-based physical activity bouts

Duncan GE, Hurvitz PM, Moudon AV, Avery AR, Tsang S. This study examined how buffer type (shape), size, and the allocation of activity bouts inside buffers that delineate the neighborhood spatially produce different estimates of neighborhood-based physical activity. A sample of 375 adults wore a global positioning system (GPS) data logger and accelerometer over 2 […]

Is COVID-19 keeping us up at night? Stress, anxiety, and sleep among adult twins

Tsang S, Avery AR, Seto EYW, Duncan GE In response to the COVID-19 pandemic, a variety of social distancing measures to mitigate the virus outbreak have been implemented. These measures may have unintended consequences on individuals’ well-being, such as increased stress, anxiety, and sleep disruptions. We investigated the extent to which individuals’ mental health status […]

Fear and depression linked to COVID-19 exposure A study of adult twins during the COVID-19 pandemic

Tsang S, Avery AR, Duncan GE. Millions of people have been impacted by the novel coronavirus (COVID-19) pandemic worldwide. High infection rates and death tolls, combined with social distancing measures, may have unintended psychological consequences on individuals. The goal of this study was to examine the interrelations between COVID-19 exposure, fear of COVID-19, and depression […]

Association Between Low Back Pain and Body Mass Index in Adult Twins: An analysis of monozygotic and dizygotic twins of the Washington State Twin Registry

Liechty A, Tsang S, Turkheimer E, Duncan GE. Background Context LBP is a common and significant cause of disability worldwide, however; questions about cause still remain. Purpose To investigate the association between low back pain (LBP), body mass index (BMI), and moderate to vigorous physical activity (MVPA) in a twin sample. Study Design Cross sectional […]

Stress, Anxiety, and Change in Alcohol Use During the COVID-19 Pandemic: Findings Among Adult Twin Pairs

Avery AR, Tsang S, Seto EYW, Duncan GE. The novel coronavirus (COVID-19) has impacted the lives of people worldwide since being declared a pandemic on March 11, 2020. Social restrictions aimed at flattening the curve may be associated with an increase in stress and anxiety, which may increase the use of alcohol as a coping […]

Perceived change in physical activity levels and mental health during COVID-19: Findings among adult twin pairs

Duncan GE, Avery AR, Seto E, Tsang S Background Physical distancing and other COVID-19 pandemic mitigation strategies may have unintended consequences on a number of health behaviors and health outcomes. The purpose of this study was to investigate the association between perceived change in physical activity or exercise and mental health outcomes over the short-term […]

Psychometric and Classification Properties of the Peas in a Pod Questionnaire

Avery AR, Turkheimer E, Tsang S, Duncan GE We examined the item properties of the Two Peas Questionnaire (TPQ) among a sample of same-sex twin pairs from the Washington State Twin Registry. With the exception of the ‘two peas’ item, three of the mistakenness items showed differential item functioning. Results showed that the monozygotic (MZ) […]

Genetic and environmental variation in educational attainment: an individual-based analysis of 28 twin cohorts

Silventoinen K, Jelenkovic A, Sund R, et al. We investigated the heritability of educational attainment and how it differed between birth cohorts and cultural-geographic regions. A classical twin design was applied to pooled data from 28 cohorts representing 16 countries and including 193,518 twins with information on educational attainment at 25 years of age or […]