Contributions of Socioeconomic, Demographic, and Behavioral Risk Factors to All-Cause Mortality Disparities by Psychological Distress in the United States: A Blinder-Oaxaca Decomposition Analysis of Longitudinal Data

BACKGROUND: Previous research has shown a significant association between psychological distress (PD) and all-cause mortality. However, there is a dearth of studies quantifying the contributions of sociodemographic and behavioral characteristics to group differences in mortality. In this study, we identify factors of mortality differences by PD. METHODS: The Blinder-Oaxaca decomposition analysis was used to quantify the contributions of individual sociodemographic and behavioral characteristics to the observed mortality differences between United States (US) adults with no PD and those with serious psychological distress (SPD), using the pooled data from the 1997-2014 National Health Interview Survey prospectively linked to the 1997-2015 National Death Index (N = 263,825). RESULTS: Low educational level, low household income, and high proportions of current smokers, renters, former drinkers, and adults experiencing marital dissolution contributed to high all-cause mortality among adults with SPD. The relative percentage of all-cause mortality disparity explained by socioeconomic and demographic factors was 38.86%. Approximately 47% of the mortality disparity was attributed to both sociodemographic and behavioral risk factors. Lower educational level (21.13%) was the top contributor to higher all-cause mortality among adults with SPD, followed by smoking status (13.51%), poverty status (11.77%), housing tenure (5.11%), alcohol consumption (4.82%), marital status (3.61%), and nativity/immigrant status (1.95%). Age, sex, and body mass index alleviated all-cause mortality risk among adults with SPD. CONCLUSIONS AND GLOBAL HEALTH IMPLICATIONS: Improved education and higher income levels, and reduced smoking among US adults with SPD might eliminate around half of the all-cause mortality disparity by SPD. Such a policy strategy might lead to reductions in mental health disparities and adverse health impacts both in the US and globally.