Personality and Mortality Risk in Adulthood: Behavioral and Physiological Mechanisms - Sufficient evidence now exists that individual differences in personality traits are associated with lifespan health outcomes and longevity. Interests have shifted from these basic examinations of personality-health associations to identifying the precise mechanisms explaining why psychological traits predict health and longevity. Exploring how health behaviors and physiological function act as conduits by which personality impacts health is the logical next step of future research. Specifically, individuals scoring higher in neuroticism and lower in conscientiousness are more likely to use tobacco, illicit drugs, and greater quantities of alcohol, and are also more likely to be sedentary and have poor dietary habits. These behaviors are some of the leading behavioral contributors to poor health and increased mortality risk among older adults. Moreover, these trait levels are also associated with increased cardiovascular deterioration, impaired immune function, and unhealthy metabolic levels. Although it seems intuitive that individuals with certain personality characteristics engage in certain behaviors which over time will deteriorate physiological health and shorten the lifespan, the empirical evidence to support these explanatory pathways is lacking. Without a clearer understanding of how these processes unfold over the lifespan, the development of interventions to combat premature aging will be limited. Thus, the short-term goal of this proposal parallels NIA strategic directions to identify mechanisms through which psychological factors exert their effects on the aging process, but it also parallels the NIA long- term goal agenda of developing foundational knowledge to be used in the creation of interventions that maintain health and increase a healthy lifespan. The central hypothesis of the current proposal is that certain personality characteristics will lead to engagement in health behaviors (e.g., greater alcohol, tobacco, drug use, physical inactivity, lower health care utilization, and poor sleep habits) that will lead to dysregulation of key physiological systems, that ultimately will result in an increased mortality risk. To accomplish these goals, the proposal will utilize a coordinated analysis framework to analyze 12 archival data sources that include over 44,000 participants. Key factors to this proposal include: 1) a diverse population where generalizability of findings can be tested via replication and meta-analytic techniques; 2) analysis of repeated measures of personality, health behaviors, and objective measures of physiology to determine how change unfolds over time and establish temporal ordering of pathways; and 3) the use of sophisticated mediation analyses conducted in a structural equation modeling framework to provide the statistical evidence of direct/indirect effects. Overall, the proposed research is significant because it explores how modifiable psychological constructs impact behavior, physiology, and longevity over time. Understanding how these processes unfold in a large sample using diverse measures will provide the statistical evidence needed to support the development of interventions aimed at improving aging outcomes.
