Date Published: February 6, 2018
Publisher: Public Library of Science
Author(s): Sydney A. Martinez, Laura A. Beebe, David M. Thompson, Theodore L. Wagener, Deirdra R. Terrell, Janis E. Campbell, Raymond Niaura.
The inverse association between socioeconomic status and smoking is well established, yet the mechanisms that drive this relationship are unclear. We developed and tested four theoretical models of the pathways that link socioeconomic status to current smoking prevalence using a structural equation modeling (SEM) approach. Using data from the 2013 National Health Interview Survey, we selected four indicator variables (poverty ratio, personal earnings, educational attainment, and employment status) that we hypothesize underlie a latent variable, socioeconomic status. We measured direct, indirect, and total effects of socioeconomic status on smoking on four pathways through four latent variables representing social cohesion, financial strain, sleep disturbance, and psychological distress. Results of the model indicated that the probability of being a smoker decreased by 26% of a standard deviation for every one standard deviation increase in socioeconomic status. The direct effects of socioeconomic status on smoking accounted for the majority of the total effects, but the overall model also included significant indirect effects. Of the four mediators, sleep disturbance and psychological distress had the largest total effects on current smoking. We explored the use of structural equation modeling in epidemiology to quantify effects of socioeconomic status on smoking through four social and psychological factors to identify potential targets for interventions. A better understanding of the complex relationship between socioeconomic status and smoking is critical as we continue to reduce the burden of tobacco and eliminate health disparities related to smoking.
An inverse association between socioeconomic status and smoking exists, although the overall mechanisms remain unclear [1–5]. The body of literature around single factors and the association with smoking is extensive, yet a comprehensive understanding of the relationship and potential mediation between multiple factors is not well understood. Researchers have attempted to test theoretical models to disentangle the pathways that link socioeconomic status to smoking, but issues with small sample sizes, a lack of generalizability, and inconsistent measurement of variables have led to inconclusive findings [6–8]. A better understanding of the pathways between socioeconomic status and smoking is crucial to identify targets for interventions that will reduce tobacco-related health disparities [9–13].
We observed significant mediation between socioeconomic status and smoking through each of four latent variables: social cohesion, financial strain, sleep disturbance, and psychological distress. Although the direct influence of social cohesion on smoking was small, the overall influence of social cohesion in decreasing the probability of smoking was amplified by its effect on decreasing sleep disturbance. Sleep disturbance had no significant independent influence on smoking, but had a large total influence by increasing psychological distress which then increased the probability of smoking.