Some research has focused directly on the effects of early childhood status and deprivation on late adult health and mortality (Ben-Shlomo and Kuh, 1997; Ben-Shlomo and Smith, 1991; Blackwell et al., 2000; Felitti et al., 1998; Forsdahl, 1978, 2002; Hayward and Gorman, 2002; Moore et al., 1997; Power et al., 1990, 1998; Rahkonen et al., 1997; Wadsworth, 1991; Wadsworth and Kuh, 1997). Few such studies focus on ethnic and racial differences in the processes involved (Doblhammer, 2002; Warner and Hayward, 2002). Few studies also attempt to identify mediating mechanisms, which are important because low socioeconomic status is not itself a disease nor intrinsically tied to poorer health.
One possible mediating mechanism is access to and use of health care. Differences in health care between white and minority children and their mothers have been documented (Institute of Medicine, 2002). This may be relevant to late-life health status and mortality, though the effects of prenatal care on fetal growth and birthweight are now in dispute. The relevance of other aspects of health care—less use of prescribed medications, fewer visits to physicians, poorer compliance with vaccination schedules—has not been confirmed.
Another mediating mechanism, much more complex and virtually unexplored, involves the mutual dependence of health and socioeconomic status (discussed earlier as a possible selection process). If impoverished early environments are associated with worse health, this may limit one’s opportunities in life, which in turn may expose one to greater health risks. Health differences in adulthood could be exacerbated by such a mechanism. Some research has attempted to model the influences involved (Palloni and Milesi, 2002; Power et al., 1986), and other research has sought to determine the magnitude of the effects (Hack et al., 2002; Lundberg, 1991; Nystrom Peck, 1992; Nystrom Peck and Lundberg, 1995; Nystrom Peck and Vagero, 1987; Power et al., 1990; Wadsworth, 1986). But these efforts have met only limited success (Palloni and Milesi, 2002), and the skeptical tone of early evaluations is still appropriate today (Blane et al., 1993). The extent to which such a mechanism may account for racial and ethnic differences is unknown.
Other features of early environments that may put individuals on pathways to disadvantage include exposure to discrimination or stigmatization (as discussed above), the physical and social isolation of a group, and exposure to conflict and violence. Some research suggests that stressful events, more commonly experienced in deprived social environments, lead to poor maternal health and increase the risks of fetal underdevelopment and low birthweight (Hogue and Hargraves, 1993; Williams and Collins, 1995; Zambrana et al., 1997). Evidence from animal and human studies shows that infants subjected to abuse, lack of parental care, and, more generally, higher levels of violence and hostility experience physiological