The health gradient by socioeconomic status widens through childhood and the adult working years and then contracts after retirement (Case et al., 2002; Crimmins et al., 2004; House et al., 1994). After some age, changes in some aspects of socioeconomic status have diminishing effects on health; it is unclear which changes in aspects of socioeconomic status continue to affect health in old age.
Assessing the effect of lifetime socioeconomic conditions on health is complicated by the fact that health also affects income and wealth, especially among adults (Smith, 1999). Table 4-1 shows that those with “fair” or “poor” self-reported health in 1984 not only had much lower wealth in that year but also saw their wealth grow less than that of others over the next 10 years. Though the table does not show it, smaller gains in wealth were associated with less favorable health outcomes.
Reciprocal causation has been one of the most difficult issues to deal with in this literature, and it is often ignored or dismissed as a minor factor. However, Smith and Kington (1997) show that much of the correlation between current income and health among males in their 50s appears to be the effect of health on income, rather than the reverse, and Adams et al. (2003) argue that among the retired population, there may be no income