Medicine and Health Sciences Commons^™

Selection Homophily And Peer Influence For Adolescents’ Smoking And Vaping Norms And Outcomes In High And Middle-Income Settings, Jennifer M. Murray, Sharon Sánchez-Franco, Olga L. Sarmiento, Erik O. Kimbrough, Christopher Tate, Shannon C. Montgomery, Rajnish Kumar, Laura Dunne, Abhijit Ramalingam, Erin L. Krupka, Felipe Montes, Huiyu Zhou, Laurence Moore, Linda Bauld, Blanca Llorente, Frank Kee, Ruth F. Hunter

Economics Faculty Articles and Research

The MECHANISMS study investigates how social norms for adolescent smoking and vaping are transmitted through school friendship networks, and is the first study to use behavioral economics methodology to assess smoking-related social norms. Here, we investigate the effects of selection homophily (the tendency to form friendships with similar peers) and peer influence (a social process whereby an individual’s behavior or attitudes are affected by peers acting as reference points for the individual) on experimentally measured smoking and vaping norms, and other smoking outcomes, in adolescents from high and middle-income settings. Full school year groups in six secondary schools in Northern …

The Impact Of Vaccinations And Chronic Disease On Covid Death Rates, James L. Doti

Economics Faculty Articles and Research

This study presents a theoretical and empirical regression model to measure the efficacy of vaccinations in reducing COVID death rates across states over the 3/10/21 to 12/28/22 period. During that period, it was estimated that the availability of vaccinations resulted in a reduction of 427,000 COVID deaths in the nation. To arrive at that estimate, other covariants were held constant. In particular, it was found that chronic disease should be included as an explanatory variable to arrive at unbiased measures of the efficacy of vaccinations in reducing deaths. In addition, the percentage of people over the age of 65 was …

Metapopulation Dynamics Of Sars-Cov-2 Transmission In A Small-Scale Amazonian Society, Thomas Kraft, Edmond Seabright, Sarah Alami, Samuel M. Jenness, Paul L. Hooper, Bret Beheim, Helen Davis, Daniel K. Cummings, Daniel Eid Rodriguez, Maguin Gutierrez Cayuba, Emily J. Miner, Xavier De Lamballerie, Lucia Inchauste, Stéphane Priet, Benjamin Trumble, Jonathan Stieglitz, Hillard Kaplan, Michael Gurven

ESI Publications

The severity of infectious disease outbreaks is governed by patterns of human contact, which vary by geography, social organization, mobility, access to technology and healthcare, economic development, and culture. Whereas globalized societies and urban centers exhibit characteristics that can heighten vulnerability to pandemics, small-scale subsistence societies occupying remote, rural areas may be buffered. Accordingly, voluntary collective isolation has been proposed as one strategy to mitigate the impacts of COVID-19 and other pandemics on small-scale Indigenous populations with minimal access to healthcare infrastructure. To assess the vulnerability of such populations and the viability of interventions such as voluntary collective isolation, we …

Brain Volume, Energy Balance, And Cardiovascular Health In Two Nonindustrial South American Populations, Hillard Kaplan, Paul L. Hooper, Margaret Gatz, Wendy J. Mack, E. Meng Law, Helena C. Chui, M. Linda Sutherland, James D. Sutherland, Christopher J. Rowan, L. Samuel Wann, Adel H. Allam, Randall C. Thompson, David E. Michalik, Guido Lombardi, Michael I. Miyamoto, Daniel Eid Rodriguez, Juan Copajira Adrian, Raul Quispe Gutierrez, Bret A. Beheim, Daniel K. Cummings, Edmond Seabright, Sarah Alami, Angela R. Garcia, Kenneth Buetow, Gregory S. Thomas, Caleb E. Finch, Jonathan Stieglitz, Benjamin C. Trumble, Michael D. Gurven, Andrei Irimia

ESI Publications

Little is known about brain aging or dementia in nonindustrialized environments that are similar to how humans lived throughout evolutionary history. This paper examines brain volume (BV) in middle and old age among two indigenous South American populations, the Tsimane and Moseten, whose lifestyles and environments diverge from those in high-income nations. With a sample of 1,165 individuals aged 40 to 94, we analyze population differences in cross-sectional rates of decline in BV with age. We also assess the relationships of BV with energy biomarkers and arterial disease and compare them against findings in industrialized contexts. The analyses test three …

Prevalence Of Dementia And Mild Cognitive Impairment In Indigenous Bolivian Forager-Horticulturalists, Margaret Gatz, Wendy J. Mack, Helena C. Chui, E. Meng Law, Giuseppe Barisano, M. Linda Sutherland, James D. Sutherland, Daniel Eid Rodriguez, Raul Quispe Gutierrez, Juan Copajira Adrian, Jesus Bani Cuata, Amy R. Borenstein, Ellen E. Waters, Andrei Irimia, Christopher J. Rowan, L. Samuel Wann, Adel H. Allam, Randall C. Thompson, Michael I. Miyamoto, David E. Michalik, Daniel K. Cummings, Edmond Seabright, Angela R. Garcia, Paul L. Hooper, Thomas S. Kraft, Caleb E. Finch, Gregory S. Thomas, Jonathan Stieglitz, Benjamin C. Trumble, Michael D. Gurven, Hillard Kaplan

ESI Publications

Introduction

We evaluated the prevalence of dementia and mild cognitive impairment (MCI) in indigenous Tsimane and Moseten, who lead a subsistence lifestyle.

Methods

Participants from population-based samples ≥ 60 years of age (n = 623) were assessed using adapted versions of the Modified Mini-Mental State Examination, informant interview, longitudinal cognitive testing and brain computed tomography (CT) scans.

Results

Tsimane exhibited five cases of dementia (among n = 435; crude prevalence = 1.2%, 95% confidence interval [CI]: 0.4, 2.7); Moseten exhibited one case (among n = 169; crude prevalence = 0.6%, 95% CI: 0.0, 3.2), all age ≥ 80 years. …

Human Milk Oligosaccharide Compositions Illustrate Global Variations In Early Nutrition, Anita Vinjamuri, Jasmine C. C. Davis, Sarah M. Totten, Lauren D. Wu, Laura D. Klein, Melanie Martin, Ea Quinn, Brooke Scelza, Alicia Breakey, Michael Gurven, Grazyna Jasienska, Hillard Kaplan, Claudia Valeggia, Katie Hinde, Jennifer T. Smilowitz, Robin M. Bernstein, Angela M. Zivkovic, Michael J. Barratt, Jeffrey I. Gordon, Mark A. Underwood, David A. Mills, J. Bruce German, Carlito B. Lebrilla

ESI Publications

Background

Human milk oligosaccharides (HMOs) are an abundant class of compounds found in human milk and have been linked to the development of the infant, and specifically the brain, immune system, and gut microbiome.

Objectives

Advanced analytical methods were used to obtain relative quantitation of many structures in approximately 2000 samples from over 1000 mothers in urban, semirural, and rural sites across geographically diverse countries.

Methods

LC-MS−based analytical methods were used to profile the compounds with broad structural coverage and quantitative information. The profiles revealed their structural heterogeneity and their potential biological roles. Comparisons of HMO compositions were made between …

Examining The Impact Of Socioeconomic Variables On Covid-19 Death Rates At The State Level, James L. Doti

Economics Faculty Articles and Research

This study uses a step-wise regression model to identify the socioeconomic variables most significant in explaining COVID-19 death rates on a state-level basis. The regression tests cover the 1/1/2020 to 12/1/2020 period as well as the first and second halves of 2020. This study also uses the Oxford stringency index to measure more precisely the efficacy of governmental mandates at the state level. The results in this study rigorously showed that while the density variables were the most significant explanatory variables during the first half of the year, their significance fell during the second half. Use of the Oxford stringency …

Very Low Prevalence And Incidence Of Atrial Fibrillation Among Bolivian Forager-Farmers, Christopher J. Rowan, Michael A. Eskander, Edmond Seabright, Daniel Eid Rodriguez, Edhitt Cortez Linares, Raul Quispe Gutierrez, Juan Copajira Adrian, Daniel Cummings, Bret Beheim, Kirsten Tolstrup, Abinash Achrekar, Thomas Kraft, David E. Michalik, Michael I. Miyamoto, Adel H. Allam, L. Samuel Wann, Jagat Narula, Benjamin C. Trumble, Jonathan Stieglitz, Randall C. Thompson, Gregory S. Thomas, Hillard S. Kaplan, Michael D. Gurven

ESI Publications

Background: Atrial fibrillation is the most common arrhythmia in post-industrialized populations. Older age, hypertension, obesity, chronic inflammation, and diabetes are significant atrial fibrillation risk factors, suggesting that modern urban environments may promote atrial fibrillation.

Objective: Here we assess atrial fibrillation prevalence and incidence among tropical horticulturalists of the Bolivian Amazon with high levels of physical activity, a lean diet, and minimal coronary atherosclerosis, but also high infectious disease burden and associated inflammation.

Methods: Between 2005–2019, 1314 Tsimane aged 40–94 years (52% female) and 534 Moseten Amerindians aged 40–89 years (50% female) underwent resting 12-lead electrocardiograms to assess atrial fibrillation prevalence. …

A Model To Explain Statewide Differences In Covid-19 Death Rates, James L. Doti

Economics Faculty Articles and Research

COVID-19 death rates per 100,000 vary widely across the nation. As of September 1, 2020, they range from a low of 4 in Hawaii to a high of 179 in New Jersey. Although academic research has been conducted at the county and metropolitan levels, no research has rigorously examined or identified the demographic and socioeconomic forces that explain state-level differences. This study presents an empirical model and the results of regression tests that help identify these forces and shed light on the role they play in explaining COVID-19 deaths.

A stepwise regression model we tested exhibits a high degree of …

Mechanisms Study: Using Game Theory To Assess The Effects Of Social Norms And Social Networks On Adolescent Smoking In Schools—Study Protocol, Ruth F. Hunter, Felipe Montes, Jennifer M. Murray, Sharon C. Sanchez-Franco, Shannon C. Montgomery, Joaquín Jaramillo, Christopher Tate, Rajnish Kumar, Laura Dunne, Abhijit Ramalingam, Erik O. Kimbrough, Erin Krupka, Huiyu Zhou, Laurence Moore, Linda Bauld, Blanca Llorente, Olga L. Sarmiento, Frank Kee

Economics Faculty Articles and Research

This proof of concept study harnesses novel transdisciplinary insights to contrast two school-based smoking prevention interventions among adolescents in the UK and Colombia. We compare schools in these locations because smoking rates and norms are different, in order to better understand social norms based mechanisms of action related to smoking. We aim to: (1) improve the measurement of social norms for smoking behaviors in adolescents and reveal how they spread in schools; (2) to better characterize the mechanisms of action of smoking prevention interventions in schools, learning lessons for future intervention research. The A Stop Smoking in Schools Trial (ASSIST) …

Immune Function During Pregnancy Varies Between Ecologically Distinct Populations, Carmen Hové, Benjamin C. Trumble, Amy S. Anderson, Jonathan Stieglitz, Hillard Kaplan, Michael Gurven, Aaron Blackwell

ESI Publications

Background and objectives

Among placental mammals, females undergo immunological shifts during pregnancy to accommodate the fetus (i.e. fetal tolerance). Fetal tolerance has primarily been characterized within post-industrial populations experiencing evolutionarily novel conditions (e.g. reduced pathogen exposure), which may shape maternal response to fetal antigens. This study investigates how ecological conditions affect maternal immune status during pregnancy by comparing the direction and magnitude of immunological changes associated with each trimester among the Tsimane (a subsistence population subjected to high pathogen load) and women in the USA.

Methodology

Data from the Tsimane Health and Life History Project (N = 935) and …

Differences In Tsimane Children’S Growth Outcomes And Associated Determinants As Estimated By Who Standards Vs. Within-Population References, Melanie Martin, Aaron Blackwell, Hillard Kaplan, Michael Gurven

Economics Faculty Articles and Research

Anthropometric measures are commonly converted to age stratified z-scores to examine variation in growth outcomes in mixed-age and sex samples. For many study populations, z-scores will differ if calculated from World Health Organization (WHO) growth standards or within-population references. The specific growth reference used may influence statistical estimates of growth outcomes and their determinants, with implications for biological inference. We examined factors associated with growth outcomes in a sample of 152 Tsimane children aged 0–36 months. The Tsimane are a subsistence-scale population in the Bolivian Amazon with high rates of infectious disease and growth faltering. To examine the influence of …

Ecological Determinants Of Respiratory Health: Examining Associations Between Asthma Emergency Department Visits, Diesel Particulate Matter, And Public Parks And Open Space In Los Angeles, California, Jason A. Douglas, Reginald S. Archer, Serena E. Alexander

Health Sciences and Kinesiology Faculty Articles

Los Angeles County (LAC) low-income communities of color experience uneven asthma rates, evidenced by asthma emergency department visits (AEDV). This has partly been attributed to inequitable exposure to diesel particulate matter (DPM). Promisingly, public parks and open space (PPOS) contribute to DPM mitigation. However, low-income communities of color with limited access to PPOS may be deprived of associated public health benefits. Therefore, this novel study investigates the AEDV, DPM, PPOS nexus to address this public health dilemma and inform public policy in at-risk communities. Optimized Hotspot Analysis was used to examine geographic clustering of AEDVs, DPM, and PPOS at the …

Historical Health Conditions In Major Us Cities: The Hue Data Set, Carlos Villareal, Brian Bettenhausen, Eric Hanss, Jonathan Hersh

Economics Faculty Articles and Research

The Historical Urban Ecological data set is a new resource detailing health and environmental conditions within seven major U.S. cities during the study period from 1830 to 1930. Researchers collected and digitized ward-level data from annual reports of municipal departments that detail the epidemiological, economic, and demographic conditions within each city. They then drafted new geographic information system data to link the tabular records to ward geographies. These data provide a new foundation to revisit questions surrounding the urban mortality transition and the growth of U.S. cities.