Background: The role of early personality in socioeconomic inequalities in health is not well understood. We investigated the extent to which type A components in adolescence and early adulthood contributed to the inverse association between education and behavioural cardiovascular disease risk factors in adulthood.
Methods: Prospective cohort study with a population-based random sample of 477 men and 648 women, aged 12-21 years at baseline. Baseline data included information on pathogenic and protective components of type A behaviours (impatience, aggression, hard-driving, and engagement-involvement) and parental education. The 9-year follow-up data included information on the participant's educational level and health behaviours (smoking, alcohol consumption, physical inactivity, butter use).
Results: After adjustment for parental education, high levels of impatience and low levels of hard-driving in adolescence and early adulthood predicted low educational level in adulthood (Ps < 0.01 for men, Ps < 0.001 for women). Adulthood education was inversely associated with smoking in women and men (odds ratios [OR] = 8.5 and 7.9, 95% CI: 3.4-18.4 and 3.1-23.9, respectively), and with physical inactivity in women (OR = 5.4, 95% CI: 2.6-11.4). In men, components of type A behaviour explained 28.5% of the inverse association between education and smoking, even after controlling for parental education. In women, the corresponding proportions were 20.5% and 17.7% for smoking and physical inactivity, respectively.
Conclusions: The inverse associations of adulthood education with smoking in men and women and physical inactivity in women may be partly rooted in personality-related factors present earlier in life. Our evidence suggests that personality should be studied as a potential contributor to socioeconomic differences in health behaviours.