Political parties and mortality: The role of social status and personal responsibility.

Previous research findings across a variety of nations show that affiliation with the conservative party is associated with greater longevity; however, it is thus far unclear what characteristics contribute to this relationship. We examine the political party/mortality relationship in the United States context. The goal of this paper is two-fold: first, we seek to replicate the mortality difference between Republicans and Democrats in two samples, controlling for demographic confounders. Second, we attempt to isolate and test two potential contributors to the relationship between political party affiliation and mortality: (1) socioeconomic status and (2) dispositional traits reflecting a personal responsibility ethos, as described by the Republican party. Graduate and sibling cohorts from the Wisconsin Longitudinal Study were used to estimate mortality risk from 2004 to 2014. In separate Cox proportional hazards models controlling for age and sex, we adjusted first for markers of socioeconomic status (such as wealth and education), then for dispositional traits (such as conscientiousness and active coping), and finally for both socioeconomic status and dispositional traits together. Clogg's method was used to test the statistical significance of attenuation in hazard ratios for each model. In both cohorts, Republicans exhibited lower mortality risk compared to Democrats (Hazard Ratios = 0.79 and 0.73 in graduate and sibling cohorts, respectively [p < 0.05]). This relationship was explained, in part, by socioeconomic status and traits reflecting personal responsibility. Together, socioeconomic factors and dispositional traits account for about 52% (graduates) and 44% (siblings) of Republicans' survival advantage. This study suggests that mortality differences between political parties in the US may be linked to structural and individual determinants of health. These findings highlight the need for better understanding of political party divides in mortality rates.