changes in hormonal regulatory mechanisms, changes that are precursors of and a predisposition to various chronic conditions (Bornstein and Cote, 2001; Coe, 1999; Francis et al., 1999; Hertzman et al., 2002). Experiencing certain environments may “mark” individuals—perhaps through a number of physiological imprinting mechanisms—in ways that could increase the risk of later morbidity.
Understanding the implications of early life events, as well as of events over the life course, may in some cases require a focus on health in late life or even at the oldest ages. People who live to extremely old ages tend to remain healthy and functional much longer than others (Hitt et al., 1999). Expanding knowledge of the extremely long-lived population holds special significance for racial and ethnic minorities. For instance, the Hispanic paradox—the better health of Hispanics relative to better-off whites (Franzini et al., 2001)—raises the question of whether there is a robust aging minority population that might reward study.
Improving understanding of the consequences of early experiences for differences in adult health and mortality is a complex task. Several interrelated types of work are needed. First, research is needed to identify key early experiences and the precise mediating mechanisms through which they affect later health. Though some important factors have been identified, more work needs to be done. Also needed is better understanding of the conditions that enhance or inhibit the effects of such factors. Second, research is needed to better document racial and ethnic differences in these early experiences. Only limited and superficial evidence on this is now available. Third, research is needed to determine whether the effects of early experiences and initial differences in them actually account for some portion of racial and ethnic differences at older ages. This issue remains unexplored.
Research Need 16: Place particular emphasis on panel studies that follow cohorts over time in order to study differences in health among racial and ethnic groups over the life course.
Such panel studies should include physiological and psychological measures as well as assessments of environmental conditions. Some such studies are in progress, following British and Canadian cohorts (Hertzman et al., 2002; Wadsworth, 1991). Other large longitudinal studies of somewhat different design, such as the National Longitudinal Survey of Youth (NLSY) and the Panel Study of Income Dynamics in the United States and a survey like the NLSY in Canada can be used for partial tests of some hypotheses. One convenient way to produce panel data might be to follow