Estimating Contributions of Social and Behavioral Factors to Cardiovascular Disease, Cancer, COPD, and Unintentional-Injury Mortality Disparities by Psychological Distress in the United States: A Blinder-Oaxaca Decomposition Analysis of the 1997-2014 NHIS

Abstract

Background: Previous research has shown a significant association between psychological distress (PD) and cause-specific mortality, but contributions of sociodemographic and behavioral characteristics to mortality differences by PD are not fully explored. Methods: The Blinder-Oaxaca decomposition analysis was used to quantify the contributions of individual sociodemographic and behavioral characteristics to the observed cardiovascular disease (CVD), cancer, chronic obstructive pulmonary disease (COPD), and unintentional-injury mortality disparities between United States (US) adults with no PD and those with serious psychological distress (SPD), using the pooled 1997-2014 data from the National Health Interview Survey prospectively linked to the National Death Index (N=263,825). Results: Lower levels of education and household income, and higher proportions of current smokers, former drinkers, non-married adults, US-born, and renters contributed to higher mortality for adults with SPD. The relative percentage of mortality explained by sociodemographic and behavioral factors was highest for cancer mortality (71.25%) and lowest for unintentional-injury mortality (20.19%). Enhancing education level among adults with SPD would decrease approximately 30% of cancer or CVD mortality disparity, and around 10% of COPD and unintentional-injury mortality disparities. Half of the cancer mortality disparity (47.4%) could be attributed to a single factor, smoking. Increasing income level will decrease 7 to 13% of the disparity in cause-specific mortality. Higher proportions of renters explained higher CVD and COPD mortality among adults with SPD by 7% and 3%, respectively. Higher proportions of former drinkers explained higher CVD, cancer, and COPD mortality among adults with SPD by 6%, 7%, and 3%, respectively. Younger age, higher proportion of females, and higher BMI among adults with SPD mitigated the mortality disparities. Conclusion and Implications for Translation: Improved education and income levels, and reduced smoking among US adults with SPD would eliminate around 90% of the cancer mortality disparity by SPD, and half of the CVD mortality disparity.