Archives: News

Please mark your calendars and plan to attend the tenth Add Health Users Conference to be held in Bethesda, Maryland, July 26-27, 2012. The Call for Papers will be posted on the Add Health web site on February 17. Conference registration will be available on-line May 30. Hope to see you there.

Data from Wave IV of the National Longitudinal Study of Adolescent Health (Add Health) provide new insights on the living arrangements of young adults (ages 24 to 32). Compared to young men and women of 30 years ago, young adults today are experiencing a longer transition between adolescence and adulthood, and there is considerable diversity in the timing of reaching traditional adult milestones such as family formation and home ownership.  Compared to twenty-something young adults, adults in their early 30s and those with greater financial independence tend to fit the traditional profile where they live in and own their home, are married, and have children.  However, more than one in ten young adults live with their parents, and one in five without a college education live at home.  Cohabitation among non-married couples is common and is observed across all racial/ethnic groups. A detailed report of the study’s findings about the living arrangements of young adults can be found in the Research Brief.

Living Arrangements in Young Adulthood: Results from Wave IV of the National Longitudinal Study of Adolescent Health. Suzanne P. Hallquist, M.S.P.H., Carmen Cuthbertson, M.C.N., Ley Killeya-Jones, Ph.D., Carolyn Tucker Halpern, Ph.D., and Kathleen Mullan Harris, Ph.D. Carolina Population Center, UNC-Chapel Hill, NC.

May 25, 2011

UNC News Release

For immediate use: Wednesday, May 25, 2011

The number of young adults in the United States with high blood pressure may be much higher than previously reported, according to a new study by researchers at the University of North Carolina at Chapel Hill.

Researchers analyzed data on more than 14,000 men and women between 24 and 32 years old in 2008 from the National Longitudinal Study of Adolescent Health, known as Add Health, funded by the National Institutes of Health. They found 19 percent of the study population had elevated blood pressure, also referred to as hypertension. However, only 11 percent of the study population had ever been told by a health care provider that they had hypertension.

“The findings are significant because they indicate that many young adults are at risk of developing heart disease, but are unaware that they have hypertension,” said Quynh Nguyen, a doctoral student at UNC’s Gillings School of Global Public Health and the study’s lead author. Hypertension is a strong risk factor for stroke and coronary heart disease, the leading cause of death for adults in the U.S.

The findings were published online Monday, May 23, 2011, in the journal Epidemiology.

Kathleen Mullan Harris, Ph.D., Add Health’s principal investigator, interim director of the UNC Carolina Population Center and a co-author of the paper, said the findings were noteworthy because they were from the first nationally representative, field-based study of blood pressure to focus on young adults. Other studies have concentrated on older adult populations, in which hypertension is more common, or have included only a small number of young adults, making it difficult to draw conclusions about that age group.

Harris said that the high rate of hypertension among the Add Health study participants was surprising. Another widely cited and reputable study – the National Health and Nutrition Examination Survey, or NHANES – reported a much lower rate of hypertension (4 percent) for a similar age group around the same time period (2007-2008). Both studies use the same definition of hypertension: a blood pressure reading of 140/90 mmHg (millimeters of mercury) or more.

“Our respective findings may differ, but the message is clear,” said Harris. “Young adults and the medical professionals they visit shouldn’t assume they’re not old enough to have high blood pressure. This is a condition that leads to chronic illness, premature death and costly medical treatment.

“Our results show that the processes that trigger these problems begin early in life, but they are preventable, so it’s important to check for hypertension now and head it off at the pass, in order to avoid these health and societal costs later on,” Harris said.

UNC researchers considered several possible explanations for the discrepancy between the Add Health and NHANES estimates, including differences in the characteristics of participants, where they were examined (at home vs. examination center) and the accuracy and reliability of the measured blood pressures. None of these factors, however, could account for the gap in the hypertension estimates between the two surveys.

Also notable was the Add Health finding that the number of young adults with elevated blood pressure was almost twice the number who reported being previously told by a health-care provider that they had hypertension (11 percent). Eric Whitsel, M.D., head of the study’s biology core, said that the finding was in line with expectations that measuring blood pressure will identify hypertension in otherwise healthy young adults who were unaware they had the condition. That pattern was reversed in NHANES, where the number of people found to have hypertension at the exam (4 percent) was half the number who reported a history of hypertension (9 percent).

The Add Health study also found males were much more likely than females to have hypertension (27 percent vs. 11 percent); and young adults without a high school degree were more likely than their college-educated peers to have the condition (22 percent vs. 17 percent).

The paper is titled “Discordance in National Estimates of Hypertension Among Young Adults.” UNC authors were Nguyen; Harris, also James E. Haar Distinguished Professor of Sociology in the College of Arts and Sciences; Whitsel, research associate professor of epidemiology and medicine in the schools of public health and medicine, respectively; Joyce Tabor and Pamela Entzel with the Carolina Population Center; Chirayath Suchindran, Ph.D., professor of biostatistics in the public health school; and Jon Hussey, Ph.D., research assistant professor, and Carolyn Tucker Halpern, Ph.D., professor of maternal and child health, both in the public health school. Yan Lau, a doctoral student in the department of economics at Princeton University, also contributed to the paper.

The National Longitudinal Study of Adolescent Health is funded by grants from the Eunice Kennedy Shriver National Institute of Child Health and Human Development, one of the National Institutes of Health. It also receives co-funding from 23 other federal agencies and foundations.

To read the paper, go to http://dx.doi.org/10.1097/EDE.0b013e31821c79d2 (subscription required).

National Longitudinal Study of Adolescent Health website: https://addhealth.cpc.unc.edu

Media note: Harris can be reached at (919) 966-1710 or kathie_harris@unc.edu.

Carolina Population Center contact: Lori Delaney (919) 966-4562, lori_delaney@unc.edu

News Services contact: Patric Lane, (919) 962-8596, patric_lane@unc.edu

The Add Health team is pleased to announce the release of the Wave IV public use data.  

Wave IV consists of data from the most recent of four in-home interviews which have followed a nationally representative sample of adolescents since they were in grades 7-12 during the 1994-195 school year. The Wave IV interviews were completed in 2008, when the sample was aged 24-32.  Add Health combines longitudinal survey data on respondents’ social, economic, psychological, and physical well-being with data on the family, neighborhood, community, school, friendships, peer groups, and romantic relationships.

The Wave IV public use data are available for download from Add Health study page on the Inter-University Consortium for Political and Social Research’s website.  

A new study showing that gay, lesbian, and bisexual adolescents are more likely to be singled out for punishment by schools and courts than their heterosexual peers was recently published in Pediatrics and featured in the New York Times.

The study, which was conducted by Kathryn Himmelstein and Hannah Brueckner of Yale University, is based on seven years of data from the National Longitudinal Study of Adolescent Health (Add Health).  The authors reviewed data on nonviolent misdeeds like alcohol use, lying to parents, shoplifting, and vandalism along with more serious crimes such as selling drugs, using a weapon, or committing burglary.  They found that Lesbian, gay, and bisexual youth were more likely to be expelled from school, arrested, or stopped by the police than their peers, even though they were less likely to engage in violence and other serious misdeeds.  Girls who self-identified as lesbian or bisexual appeared to be at highest risk for punishment.

Although the study was not designed to investigate the reasons why non-heterosexual students are disproportionately punished, the authors suggested that the findings may reflect discrimination by school or court officials against non-heterosexuals, or that non-heterosexuals might receive less support from the education, health care, and child welfare systems than their straight peers.

News source:

Parker-Pope, Tara. “Schools and Legal System Mistreat Gays, Study Says” The New York Times (on-line December 6, 2010)

To read the entire New York Times article, click here.  Some media outlets may require free user registration or a subscription. Most articles are available at the URLs provided for a limited time, usually two weeks or less.

Study source:

Himmelstein, Kathryn E.W. and Hannah Bruckner. (2010). Criminal-Justice and School Sanctions Against Nonheterosexual Youth: A National Longitudinal Study. Pediatrics.  Published on-line December 6, 2010.  DOI:10.1542/peds.2009-2306

A new study based on data from the National Longitudinal Study of Adolescent Health (Add Health) suggests that genetics may play a role in shaping adults’ political leanings.  The research, which appeared in the latest edition of The Journal of Politics, focused on a dopamine receptor gene called DRD4.  The DRD4 gene has previously been shown to influence people’s novelty-seeking behavior, but this is the first time it has be linked to the development of political views.

The study’s lead researcher, James H. Fowler of the University of California, San Diego, matched genetic information on 2,000 Add Health participants with “maps” of their social networks.  He found that those with a specific variant of the DRD4 gene were more likely to be liberal as adults – though only if they had an active adolescent social life.  The finding held true regardless of the participant’s ethnicity, culture, sex, or age.

The key to it all, the study suggests, is that liberals are more open.  Talking with FoxNews, Fowler hypothesized that “people with the novelty-seeking [DRD4] gene variant would be more interested in learning about their friends’ points of view.  As a consequence, people with this genetic predisposition who have a greater-than-average number of friends would be exposed to a wider variety of social norms and lifestyles, which might make them more liberal than average” (October 28, 2010. Researchers Find the ‘Liberal Gene’.  Published on FoxNews.com).

“These finding suggest that political affiliation is not based solely on the kind of social environment people experience,” the authors concluded in the report.  “It is our hope is that more scholars will begin to explore the potential interaction of biology and environment.”

To read the entire FoxNews article, click here.

Some media outlets may require free user registration or a subscription. Most articles are available at the URLs provided for a limited time, usually two weeks or less.

This article is based on research published as the following:

Settle, Jamie E.; Dawes, Christopher T.; Christakis, Nicholas A.; and James H. Fowler. 2010. Friendships Moderate an Association between a Dopamine Gene Variant and Political Ideology. The Journal of Politics, 72: 1189-1198. Cambridge University Press.  DOI: 10.1017/S0022381610000617.

US News & World Report published an article from ScienceNews which discusses the presentation of research by CPC Fellows Guang Guo and Kathleen Mullan Harris at a recent meeting of the American Sociological Association. The findings suggest teenage boys with two copies of a particular gene variant are less likely to engage in risky behaviors than their counterparts who carry at least one copy of a different version of the gene. The findings show that once the behavior becomes socially acceptable or legal the likelihood to engage becomes more even between the two groups. The results are especially significant in that they show the possibility of a level of genetic protection from unsafe social behaviors.

Guo is Professor of Sociology at UNC-Chapel Hill. Harris is James Haar Distinguished Professor of Sociology at UNC-Chapel Hill and Interim Director of CPC. Matt Bradshaw, CPC Postdoctoral Scholar, also commented on the study in the story.

The study was published in PLoS ONE in February 2010.

The full article can be read here. It originally appeared here.

News source:

Bower, Bruce. “Sociologists looking at risky behavior plunge into the gene pool” ScienceNews (August 15, 2010)

Bower, Bruce. “Sociologists looking at risky behavior plunge into the gene pool” US News & World Report (August 16, 2010)

Study source:

Guo, Guang, Cai, Tianji, Guo, Rui, Wang, Hongyu, Harris, Kathleen Mullan. (2010) The Dopamine Transporter Gene, a Spectrum of Most Common Risky Behaviors, and the Legal Status of the Behaviors. PLoS ONE 5(2): e9352. February 2010.

On July 22-23, 2010, the ninth Add Health Users Conference took place in Bethesda, Maryland on the campus of the National Institutes of Health (NIH).  Over 100 researchers who are working with Add Health data assembled to share research goals, experiences and results.  The conference agenda included over 50 presentations by investigators who are using Add Health data to conduct research in substantive areas spanning the social, behavioral and biological sciences.  In addition, methodology sessions provided in-depth information on the Add Health study design and the unique biomarker, genetic, geographic and relationship data that enhance this rich data set.  Conference materials and methodology presentations are available at the links below.

2010 Add Health Users Conference Materials

Program

Abstracts

Participants and Research Information

2010 Add Health Users Conference Methodology Session Presentations

Overview of Add Health Study and Design

by Kathleen Mullan Harris

Access to Add Health Data at ICPSR

by Felicia LeClere
Biomarkers – Part 1
Biomarkers – Part 2
Biomarkers – Part 3

by Eric Whitsel

Relationship and Fertility Data: Wave IV

by Mariah Mantsun Cheng

ONEdata: Obesity & Neighborhood Environmental Data

by Misa Graff

Using Genetic Data in the Add Health Sample – Part A

Using Genetic Data in the Add Health Sample – Part B

by Andy Smolen

Add health Wave IV Non-response: Patterns of Wave-Specific Rates and Non-response Biases for the Full Weighted Sample

by Naomi Brownstein

Investigation of Ways of Handling Sampling Weights for Multilevel Model Analyses Using Add Health

by Tianji Cai

On Monday, July 12, 2010, Dr. Kathleen Mullan Harris, Director and Principal Investigator of the Add Health study, will speak at a Congressional Briefing titled “Recession and Recovery: How are Americans Affected?” in Washington, D.C.  The briefing is being sponsored by the Population Association of America (PAA).  Using data from Wave IV of the Add Health study, Dr. Harris will discuss how the economic downturn has particularly affected young adults.  Other panelists will speak about the effects of the recession on children and older Americans.

For more information about the briefing, please view the attached flier.

For more information about the Add Health study, please visit our homepage.

Dr. Kathleen Mullan Harris, Director and Principal Investigator of the Add Health study, presented novel findings based on Add Health genetics data at the “Integrating Genetics and the Social Sciences” conference in Boulder, Colorado on June 2-3, 2010.

Dr. Harris’ paper titled “The Dopamine Transporter Gene, a Spectrum of Most Common Risky Behaviors, and the Legal Status of the Behaviors” was featured in the opening session of the meeting.  The paper examines the protective effect of the dopamine transporter gene (DAT1) across a spectrum of common risky behaviors including delinquency, sexual activity, smoking, and substance use.

To view Dr. Harris’ PowerPoint presentation, please click here.

To view the scholarly paper on which the presentation was based, please click here.

For more information about the meeting, please visit the Integrating Genetics and the Social Sciences conference website.