Objective: Childhood economic upward mobility (i.e., increases in family income across childhood) may attenuate links between childhood poverty and systemic inflammation in adulthood, the extent of which may vary depending on inter-individual differences in personality characteristics, including hostility. Methods: N =171 men who experienced low income in toddlerhood were followed prospectively into adulthood. Annual family income was collected 12 times when men were 1.5-17 years old. Men completed the Cook-Medley Hostility Scale and had their fasting blood drawn to measure circulating levels of C-reactive protein (CRP) at age 32. Multiple linear regression analyses examined main and moderation effects of childhood economic upward mobility and adult hostility on CRP levels adjusting for income at 1.5 years, race, parent educational attainment, and adult income, education, waist circumference, and smoking status. Results: Main effects were non-significant, but an interaction effect emerged. Counter to expectations, childhood economic upward mobility related to greater adult CRP as trait hostility decreased (𝛽=−0.203, P =0.018). Simple slope analyses further revealed that childhood economic upward mobility was positively associated with CRP among men lower in hostility (𝛽=0.23, SE=0.09, P =0.020) but was unrelated to CRP among men higher in hostility. Results of post-hoc sensitivity analyses are also discussed. Conclusions: Counterintuitive findings suggest that for men who experience poverty in toddlerhood, the association between childhood economic upward mobility and adult CRP may be nuanced and even in the positive direction for men low in hostility, which aligns with work on unintended health consequences of upward mobility.
Jones et al. (Mon,) studied this question.