This dissertation contributes toward our understanding of health disparities by examining how stress, namely underemployment, over the life course affects mental and physical health outcomes. Using data from the 1979 National Longitudinal Survey of Youth, this study employs conditional latent class models with distal health outcomes to render life course trajectories of underemployment spanning a 10-year period, as well as antecedent life course pathways originating in childhood, and the health consequences at mid-adulthood. More specifically, a multinomial logistic regression function is used to relate the underemployment latent class categorical variable to covariates; and, linear, logistic, and zero-inflated Poisson regression functions are used to relate the health outcomes to the underemployment latent class trajectories and covariates.
The results suggest that approximately one-third of women and one-fourth of men belong to trajectories, or latent classes, characterized by chronic moderate levels of underemployment over the adult life course. In addition, various trajectories revealed the multifarious nature of stress by demonstrating unique patterns of severity, duration, timing, and sequencing of underemployment. Findings confirmed past positive associations between underemployment and being African American or having lower education levels. And, of principal interest in this dissertation, results demonstrated that membership in worse underemployment trajectories was generally associated with higher levels of depression and worse self-rated health, but not binge drinking or chronic conditions at mid-adulthood for women and men.
Furthermore, the results suggest that a cumulative process is at play whereby adverse childhood conditions, including lower parental education and several measures of family and other disadvantages, operate by impeding educational attainment and/or increasing the odds of membership in a higher-risk underemployment trajectory, which ultimately harms health. There is also evidence that those who have higher levels of baseline depression are disproportionately selected into worse underemployment trajectories.
Ultimately, these findings indicate that the underemployed must be disaggregated from the employed in future research, whether employment status is the focus of interest or a control variable. They also highlight the need to theoretically and methodologically engage the dynamic nature of stress, as well as situate stress in a life course framework whereby heterogeneous pathways over the life course originating in childhood are examined.