Childhood socioeconomic status and host resistance to infectious illness in adulthood

Objective: Low childhood socioeconomic status (SES) is a risk factor for adult morbidity and mortality primarily attributable to cardiovascular disease. Here, we examine whether childhood SES is associated with adult host resistance to infectious illness, and whether the effect is limited to a critical period of low SES exposure, can be undone by changes in childhood SES, and is explained by adult SES. Methods: Three hundred thirty-four healthy volunteers reported their own and their parents' level of education and the ages during their childhood when their parents owned their homes. Volunteers' current home ownership was recorded from real estate records. Subsequently, they were given nasal drops containing 1 of 2 rhinoviruses and were monitored in quarantine for infection and signs/symptoms of a common cold. Results: For both viruses, susceptibility to colds decreased with the number of childhood years during which their parents owned their home (odds ratios by tertiles adjusted for demographics, body mass, season, and prechallenge viral-specific immunity were 3.7 for fewest years, 2.6 and 1). This decreased risk was attributable to both lower risk of infection and lower risk of illness in infected subjects. Moreover, those whose parents did not own their home during their early life but did during adolescence were at the same increased risk as those whose parents never owned their home. These associations were independent of parent education level, adult education and home ownership, and personality characteristics. Conclusions: A marker of low income and wealth during early childhood is associated with decreased resistance to upper respiratory infections in adulthood. Higher risk is not ameliorated by higher SES during adolescence and is independent of adult SES.