Big Data and Important Questions: Population Health Studies in the United States, China, and the Philippines
Carolina Population Center’s researchers have decades of experience collecting, analyzing, sharing, and archiving big data sets of population research studies. CPC Fellow Barry M. Popkin is one of several CPC Fellows who are at the forefront of research efforts to assess the critical role of nutritional, social, and environmental factors in population health. One of his core contributions has been collaborations on the design and implementation of large public use data sets collected from cohorts in the US, Russia, China, and the Philippines. These large, population-based cohorts are major vehicles used to develop multidisciplinary research on an array of population health topics, exploring issues such as:
- how changing patterns of diet and physical activity affect the burden of chronic disease risk;
- efficient strategies for combating the persistent infectious disease burden;
- the interplay of social, environmental, and biological influences on well-being; and
- health disparities by race, gender, and socioeconomic factors.
CPC Fellows Linda Adair, Penny Gordon-Larsen, Michelle Mendez, Shu Wen Ng, and Amanda Thompson have benefited from Popkin’s expertise in big data and have become experts in the studies, and in many cases, have expanded their scope. CPC Fellow David Guilkey has frequently collaborated with Popkin and others on these studies.
Building on their central role in defining and studying global trends in the nutrition transition in low- and middle-income countries, these CPC Fellows are extending their work to characterize population changes in diet, physical activity, and obesity, and to:
- quantify adverse effects of these changes on proximate markers of population health risk,
- identify key drivers of these shifts, and
- lead the design and evaluation of large-scale studies to prevent chronic disease risk.
CPC’s US-based nutrition and population health research continues to focus on obesity, a leading underlying cause of death and disability in this country. Fellows Popkin, Ng, and others are evaluating a major initiative undertaken by leading manufacturers of consumer-packaged goods who pledged to collectively remove 1.5 trillion calories from the US marketplace to combat child obesity. This innovative research uses longitudinal data on purchases from more than 100,000 households, along with national surveillance data from the National Health and Nutrition Examination Survey (NHANES). Analysis of these data integrates modeling strategies from econometrics, statistics, and nutritional epidemiology. Results to date demonstrate there have been significant declines in calories purchased from the packaged food and beverage sector, but that these declines are largely attributable to trends initiated prior to the corporate pledge. Moreover, further analyses show that caloric intakes have recently increased in some child subpopulations (e.g., low-income, black, and Latino) that are at highest risk of obesity.
International work in this area includes mentored research on issues such as environmental change and inflammation (led by Thompson) and on cardiometabolic risk across the lifecycle (led by Gordon-Larsen, Popkin, and Adair). Both research areas use CPC’s China Health and Nutrition Survey (CHNS), an NIH-funded study of more than 21,000 individuals followed over 25 years. Using structural equation models, CPC researchers are examining the complex pathways through which community-, household-, and individual-level factors affect diet and physical activity, the degree and timing of weight gain, and ultimately cardiometabolic risk across the lifecycle. In recent publications, CPC Fellows have examined: the influence of specific aspects of urbanicity on obesity; inflammation and diabetes relationships between 15- to 18-year trajectories in diet and weight and cardiometabolic risk in adults; and the role of nutritional factors in cardiometabolic risk beginning in childhood, dynamic modeling of the full set of factors affecting obesity and modeling of other specific components such as physical activity, among others. Over 20,000 researchers have used and analyzed the CHNS data to address complex economic, aging, nutrition, and health issues. In 2015, the tenth wave of CHNS data will be collected and subsequently made available to the research community.
The Cebu Longitudinal Health and Nutrition Survey has followed a cohort of about 2,000 Filipino women for more than 30 years, and current NIH-funded work focuses on exploring multidimensional pathways to maintaining health through the life course. This work integrates three decades of data on women’s health, nutrition, reproductive, work, physical activity, and social histories to understand factors that contribute to chronic disease risk, functional outcomes, and mental and cognitive health. This study also incorporates in-depth study of grand-parenting roles and their relationship to maternal depression and functional health. Prior work on this cohort has documented dramatic changes in overweight and obesity, and high levels of chronic disease risk factors.
CPC’s dedication to sharing original data
CPC collects and shares data on these and many other longitudinal studies. These and other CPC projects allow for tests of multilevel processes (i.e., those involving the effects of and interactions among social, environmental, and biological factors). The value of these data grows as the cohorts are followed and more of their life experience is observed. Enhancements to these data allow the study of genetic, spatial, and social network factors across multiple domains of experience for multiple generations. Moreover, these projects have an important externality to CPC – the collection and analysis of these data provide foci for interdisciplinary collaboration among fellows and their colleagues.
Future research at CPC will continue to use innovative, multidisciplinary approaches to develop the evidence base needed to inform policy development and evaluation aimed at improving population health.