Childhood conscientiousness relates to objectively measured adult physical health four decades later.

Objective: Many life span personality-and-health models assume that childhood personality traits result in life-course pathways leading through morbidity to mortality. Although childhood conscientiousness in particular predicts mortality, there are few prospective studies that have investigated the associations between childhood personality and objective health status in adulthood. The present study tested this crucial assumption of life span models of personality and health using a comprehensive assessment of the Big Five traits in childhood (M age = 10 years) and biomarkers of health over 40 years later (M age = 51 years).

Methods: Members of the Hawaii Personality and Health Cohort (N = 753; 368 men, 385 women) underwent a medical examination at mean age 51. Their global health status was evaluated by well-established clinical indicators that were objectively measured using standard protocols, including blood pressure, lipid profile, fasting blood glucose, and body mass index. These indicators were combined to evaluate overall physiological dysregulation and grouped into five more homogeneous subcomponents (glucose intolerance, blood pressure, lipids, obesity, and medications).

Results: Lower levels of childhood conscientiousness predicted more physiological dysregulation (β = -.11, p < .05), greater obesity (β = -.10, p < .05), and worse lipid profiles (β = -.10, p < .05), after controlling for the other Big Five childhood personality traits, gender, ethnicity, parental home ownership, and adult conscientiousness.

Conclusions: These findings are consistent with a key assumption in life span models that childhood conscientiousness is associated with objective health status in older adults. They open the way for testing mechanisms by which childhood personality may influence mortality through morbidity; mechanisms that could then be targeted for intervention.