A growing literature has demonstrated a link between early-life
socioeconomic conditions and adult health at a singular point in life. No
research exists, however, that specifies the life course patterns of
socioeconomic status (SES) in relation to the underlying biological processes
that determine health. Using an innovative life course research design
consisting of four nationally representative longitudinal datasets that
collectively cover the human life span from early adolescence to old age (Add
Health, MIDUS, NSHAP, and HRS), we address this scientific gap and assess how
SES pathways from childhood into adulthood are associated with biophysiological
outcomes in different adult life stages. For each dataset, we constructed
standardized, composite measures of early-life SES and adult SES and harmonized
biophysiological measurements of immune and metabolic functioning. We found that
the relative importance of early-life and adult SES varied across young-, mid-,
and late-adulthood, such that early-life SES sets a life course trajectory of
socioeconomic well-being and operates through adult SES to influence health as
adults age. We also documented evidence of the detrimental health effects of
downward mobility and persistent socioeconomic disadvantage. These findings are
the first to specify the life course patterns of SES that matter for underlying
biophysiological functioning in different stages of adulthood. The study thus
contributes new knowledge critical for improving population health by
identifying the particular points in the life course in which interventions
might be most effective in preventing disease and premature mortality.