Linda Gottfredson shows that IQ perhaps explains a lot of the income-health gradient. If income and IQ are correlated, and if some minimal baseline cognitive capacity is needed to follow a doctor’s orders (like scheduling multiple near-conflicting prescription schedules, for example), then we’d expect an income-health gradient even if there were zero direct effect of income on health.
While intelligence is important, so too is personality. And a new metastudy suggests that conscientiousness is particularly important. The abstract:
Personality may influence the risk of death, but the evidence remains inconsistent. We examined associations between personality traits of the five-factor model (extraversion, neuroticism, agreeableness, conscientiousness, and openness to experience) and the risk of death from all causes through individual-participant meta-analysis of 76,150 participants from 7 cohorts (the British Household Panel Survey, 2006-2009; the German Socio-Economic Panel Study, 2005-2010; the Household, Income and Labour Dynamics in Australia Survey, 2006-2010; the US Health and Retirement Study, 2006-2010; the Midlife in the United States Study, 1995-2004; and the Wisconsin Longitudinal Study’s graduate and sibling samples, 1993-2009). During 444,770 person-years at risk, 3,947 participants (54.4% women) died (mean age at baseline = 50.9 years; mean follow-up = 5.9 years). Only low conscientiousness-reflecting low persistence, poor self-control, and lack of long-term planning-was associated with elevated mortality risk when taking into account age, sex, ethnicity/nationality, and all 5 personality traits. Individuals in the lowest tertile of conscientiousness had a 1.4 times higher risk of death (hazard ratio = 1.37, 95% confidence interval: 1.18, 1.58) compared with individuals in the top 2 tertiles. This association remained after further adjustment for health behaviors, marital status, and education. In conclusion, of the higher-order personality traits measured by the five-factor model, only conscientiousness appears to be related to mortality risk across populations.
So poor self-control and lack of long-term planning correlates with higher mortality risk.
Add this to the list of underlying variables that likely confound a whole lot of measured correlations between engaging in risky stuff and bad outcomes.