Rising health challenges in the U.S.
Around the turn of the century, Americans’ health began to decline. I investigate the gender and racial differences in the long-term cohort trend in age-specific and cause-specific mortality (International Journal of Epidemiology 2019), and the cohort trend in physiological status, mental health, and health behaviors (American Journal of Epidemiology 2021). I find that for all gender and racial groups, physiological dysregulation has increased continuously from Baby Boomers through late-Gen X and Gen Y. Drug use is the predominant cause of elevated mortality among Baby Boomers while an innate physiological deterioration is the driving force behind the worsening health profiles of late-Gen X and Gen Y. I have attempted to understand the causes of population health and inequality through medical expansion (Journal of Health and Social Behavior 2018), income inequality (Social Science & Medicine 2022), and demographic mechanisms (Demographic Research 2020). Ongoing work takes a life-course perspective and investigates the early-life and adulthood factors behind this worsening health trend and the contextual socioeconomic, environmental and policy determinants.
Determinants and consequences of cognitive aging across the life course
Many studies have reported declines in the incidence and prevalence of dementia in the United States over the last few decades, which is a by-product of changes in cognitive function later in life across birth cohorts. I reexamine the cohort trend in cognitive functioning and find it has been improving from the Greatest Generation to Late Children of Depression and War Babies, but then declines significantly beginning with Early-Baby Boomers and continuing into Mid-Baby Boomers. This pattern is observed universally across genders, race/ethnicities, education, occupation, income and wealth quartiles. The worsening cognitive functioning among Baby Boomers can be attributed to lower household wealth, lower likelihood of marriage, higher levels of loneliness, depression and psychiatric problems, and elevated cardiovascular risk factors (e.g., obesity, physical inactivity, hypertension, stroke, diabetes, and heart disease) (The Journals of Gerontology: Social Sciences 2021). The worsening cognitive functioning among Baby Boomers may potentially reverse past favorable trends in dementia if no effective interventions and policy responses are put in place. Ongoing work conducts a comprehensive investigation on the relative contribution of a wide range of childhood conditions and adulthood factors to cognitive functioning trajectories and the gender and racial differences therein.
Nativity disparities in labor market, aging, and health
Despite immigrants’ lower socioeconomic status and less access to health care, they tend to have better health along many dimensions. In addition to possessing various health advantages, immigrants are known for facing especially challenging work environments and precarious labor market positions. This new project investigates how immigrants’ precarious labor market positions may alter their health advantages, whether job insecurity is equally detrimental to immigrants and the native-born, and which factors may intensify or attenuate the adverse consequences of precarious employment conditions. Moreover, different immigrant groups may fare differently because of their different occupational niches, earning trajectories, probabilities of success in the labor market, and health behaviors. The first paper examines the mortality consequence of unemployment among foreign-born people of various ethnoracial categories compared to the native-born population, the temporal changes in mortality consequences, and the heterogeneity in the impact of unemployment by gender and race/ethnicity (Journal of Social Issues 2022). The second paper proposes a new longitudinal approach to investigate immigrants’ mortality advantage over real time and finds that immigrants enjoy a persistent survival advantage over the native-born (Demography 2022).
Workplace, work, and health disparities
This project investigates workplace and work as a social determinant of health and health disparities. Particularly, it focuses on the dynamics of managerial practices, relationships, and statuses in the workplace, precarity and mismatch in the employment, and how these factors shape workers' physical and mental health and inequality therein.
The role of selection in health production and aging process
Selection is prevalent and consequential in the population patterns of health and mortality. This project investigates the role of selection in health production and aging process over the life course and across birth cohorts. It encompasses four subprojects: (1) how selection may contribute to the evolving relationship between health and health determinants (e.g., marriage, education) over the life course, and the contingencies in this relationship across the selection spectrum; (2) how different ages of onset of obesity, weight loss, and mortality selection effects may change the population compositions of body mass index groups across the life course and impact the aggregate observed effect of obesity on mortality across age groups; (3) how mortality selection and cohort evolution mechanisms shape the rate of demographic aging, the rate of biological aging, and age-dependent mortality patterns across birth cohorts in both early and later transition countries; and (4) how changes in the level and variance of unobserved frailty over time may complicate the interpretation of cohort trends in health disparities and life expectancy, and how to evaluate bias due to selection dynamics.
Around the turn of the century, Americans’ health began to decline. I investigate the gender and racial differences in the long-term cohort trend in age-specific and cause-specific mortality (International Journal of Epidemiology 2019), and the cohort trend in physiological status, mental health, and health behaviors (American Journal of Epidemiology 2021). I find that for all gender and racial groups, physiological dysregulation has increased continuously from Baby Boomers through late-Gen X and Gen Y. Drug use is the predominant cause of elevated mortality among Baby Boomers while an innate physiological deterioration is the driving force behind the worsening health profiles of late-Gen X and Gen Y. I have attempted to understand the causes of population health and inequality through medical expansion (Journal of Health and Social Behavior 2018), income inequality (Social Science & Medicine 2022), and demographic mechanisms (Demographic Research 2020). Ongoing work takes a life-course perspective and investigates the early-life and adulthood factors behind this worsening health trend and the contextual socioeconomic, environmental and policy determinants.
- Zheng, Hui, Yoonyoung Choi, Jonathan Dirlam, and Linda George. 2022. “Rising Childhood Income Inequality and Declining Americans’ Health.” Social Science & Medicine 303: 115016.
- Zheng, Hui, and Paola Echave. 2021. “Are Recent Cohorts Getting Worse? Trends in U.S. Adult Physiological Status, Mental Health, and Health Behaviors across a Century of Birth Cohorts.” American Journal of Epidemiology 190(11): 2242-2255.
- Zheng, Hui, Jonathan Dirlam, and Paola Echave. 2021. “Divergent Trends in the Effects of Early-Life Factors on Adult Health.” Population Research and Policy Review 40(5): 1119-1148.
- Zheng, Hui. 2020. “Unobserved Population Heterogeneity and Dynamics of Health Disparities.” Demographic Research 43: 1009-1048.
- Zang, Emma, Hui Zheng, Yang Claire Yang, and Kenneth C Land. 2019. “Recent Trends in U.S. Mortality in Early and Middle Adulthood: Racial/Ethnic Disparities in Inter-Cohort Patterns.” International Journal of Epidemiology 48(3): 934-944.
- Zheng, Hui and Linda K. George. 2018. “Does Medical Expansion Improve Population Health?” Journal of Health and Social Behavior 59(1): 113-132.
- Zheng, Hui, Yang Yang and Kenneth C Land. 2016. “Age-Specific Variation in Adult Mortality Rates in Developed Countries.” Population Research and Policy Review 35: 49-71.
- Zheng, Hui. 2015. “Losing Confidence in Medicine in an Era of Medical Expansion?” Social Science Research 52: 701-715.
- Zheng, Hui, and Linda K. George. 2012. “Rising U.S. Income Inequality and the Changing Gradient of Socioeconomic Status on Physical Functioning and Activity Limitations, 1984-2007.” Social Science & Medicine 75(12): 2170-82.
- Zheng, Hui. 2012. “Do People Die from Income Inequality of A Decade Ago?” Social Science & Medicine 75(1): 36-45.
- Zheng, Hui, and Kenneth C Land. 2012. “Composition and Decomposition in U.S. Gender-Specific Self-Reported Health Disparities, 1984-2007.” Social Science Research 41(2): 477-88.
- Zheng, Hui, Yang Yang, and Kenneth C Land. 2011. “Variance Function Regression in Hierarchical Age-Period-Cohort Models, with Applications to the Study of Self-Reported Health.” American Sociological Review 76(6): 955-83. PMCID:PMC3419541.
- Zheng, Hui. 2009. “Rising U.S. Income Inequality, Gender, and Individual’s Self-Rated Health, 1972-2004.” Social Science and Medicine 69(9): 1333-42.
Determinants and consequences of cognitive aging across the life course
Many studies have reported declines in the incidence and prevalence of dementia in the United States over the last few decades, which is a by-product of changes in cognitive function later in life across birth cohorts. I reexamine the cohort trend in cognitive functioning and find it has been improving from the Greatest Generation to Late Children of Depression and War Babies, but then declines significantly beginning with Early-Baby Boomers and continuing into Mid-Baby Boomers. This pattern is observed universally across genders, race/ethnicities, education, occupation, income and wealth quartiles. The worsening cognitive functioning among Baby Boomers can be attributed to lower household wealth, lower likelihood of marriage, higher levels of loneliness, depression and psychiatric problems, and elevated cardiovascular risk factors (e.g., obesity, physical inactivity, hypertension, stroke, diabetes, and heart disease) (The Journals of Gerontology: Social Sciences 2021). The worsening cognitive functioning among Baby Boomers may potentially reverse past favorable trends in dementia if no effective interventions and policy responses are put in place. Ongoing work conducts a comprehensive investigation on the relative contribution of a wide range of childhood conditions and adulthood factors to cognitive functioning trajectories and the gender and racial differences therein.
- Zheng, Hui. 2021. “A New Look at Cohort Trend and Underlying Mechanisms in Cognitive Functioning.” The Journals of Gerontology: Social Sciences 76(8): 1652-1663.
Nativity disparities in labor market, aging, and health
Despite immigrants’ lower socioeconomic status and less access to health care, they tend to have better health along many dimensions. In addition to possessing various health advantages, immigrants are known for facing especially challenging work environments and precarious labor market positions. This new project investigates how immigrants’ precarious labor market positions may alter their health advantages, whether job insecurity is equally detrimental to immigrants and the native-born, and which factors may intensify or attenuate the adverse consequences of precarious employment conditions. Moreover, different immigrant groups may fare differently because of their different occupational niches, earning trajectories, probabilities of success in the labor market, and health behaviors. The first paper examines the mortality consequence of unemployment among foreign-born people of various ethnoracial categories compared to the native-born population, the temporal changes in mortality consequences, and the heterogeneity in the impact of unemployment by gender and race/ethnicity (Journal of Social Issues 2022). The second paper proposes a new longitudinal approach to investigate immigrants’ mortality advantage over real time and finds that immigrants enjoy a persistent survival advantage over the native-born (Demography 2022).
- Zheng, Hui, and Wei-hsin Yu. 2022. “Diminished Advantage or Persistent Protection? A New Approach to Assess Immigrants’ Mortality Advantages Over Time.” Demography. 59(5): 1655-1681.
- Zheng, Hui, and Wei-hsin Yu. 2022. “Do Immigrant Health Advantages Remain After Unemployment? Variations by Race-Ethnicity and Gender.” Journal of Social Issues 78: 691-716.
Workplace, work, and health disparities
This project investigates workplace and work as a social determinant of health and health disparities. Particularly, it focuses on the dynamics of managerial practices, relationships, and statuses in the workplace, precarity and mismatch in the employment, and how these factors shape workers' physical and mental health and inequality therein.
- Roscigno, Vincent, Hui Zheng, and Martha Crowley. 2022. “Workplace Age Discrimination and Social-psychological Well-Being.” Society & Mental Health 12(3): 195-214.
- Zheng, Hui, Jacob Tarrence, Vincent Roscigno, and Scott Schieman. 2021. “Workplace Financial Transparency and Stress.” Social Science Research 95: 102525.
- Dirlam, Jonathan, and Hui Zheng. 2017. “Job Satisfaction Trajectories and Health: A Life Course Perspective.” Social Science & Medicine 178: 95-103.
The role of selection in health production and aging process
Selection is prevalent and consequential in the population patterns of health and mortality. This project investigates the role of selection in health production and aging process over the life course and across birth cohorts. It encompasses four subprojects: (1) how selection may contribute to the evolving relationship between health and health determinants (e.g., marriage, education) over the life course, and the contingencies in this relationship across the selection spectrum; (2) how different ages of onset of obesity, weight loss, and mortality selection effects may change the population compositions of body mass index groups across the life course and impact the aggregate observed effect of obesity on mortality across age groups; (3) how mortality selection and cohort evolution mechanisms shape the rate of demographic aging, the rate of biological aging, and age-dependent mortality patterns across birth cohorts in both early and later transition countries; and (4) how changes in the level and variance of unobserved frailty over time may complicate the interpretation of cohort trends in health disparities and life expectancy, and how to evaluate bias due to selection dynamics.
- Zheng, Hui, Paola Echave, and Neil Mehta. 2021. “Obesity-Mortality Link over the Life Course: The Contribution of Population Compositional Changes.” Biodemography and Social Biology 66(1): 50-68.
- Zheng, Hui. 2020. “Unobserved Population Heterogeneity and Dynamics of Health Disparities.” Demographic Research 43: 1009-1048.
- Zheng, Hui and Siwei Cheng. 2018. “A Simulation Study of the Role of Cohort Forces in Mortality Patterns.” Biodemography and Social Biology 64 (3-4): 216-236.
- Tumin, Dmitry, and Hui Zheng. 2018. “Do the Health Benefits of Marriage Depend on the Likelihood of Marriage?” Journal of Marriage and Family 80: 622-636.
- Zheng, Hui. 2017. “Why Does College Education Matter? Unveiling the Contributions of Selection Factors.” Social Science Research 68: 59-73.
- Zheng, Hui, and Jonathan Dirlam. 2016. “The BMI-Mortality Link across the Life Course: Two Selection Biases and Their Effects.” Plos One. DOI: 10.1371/journal.pone.0148178.
- Zheng, Hui, Yang Yang and Kenneth C Land. 2016. “Age-Specific Variation in Adult Mortality Rates in Developed Countries.” Population Research and Policy Review 35: 49-71.
- Zheng, Hui. 2014. “Aging in the Context of Cohort Evolution and Mortality Selection.” Demography 51(4):1295-1317.
- Zheng, Hui, Yang Yang, and Kenneth C Land. 2011. “Heterogeneity in the Strehler-Mildvan General Theory of Mortality and Aging.” Demography 48: 267-90.