Milbank Quarterly, Vol. 76, Number 3 (1998)

Adler N, Marmot M, McEwen B, and Stewart, J., eds.
"Socioeconomic Status and Health in Industrial Nations: Social, 
Psychological and Biological Pathways," Annals of the NY Academy 
of Sciences, Volume 896 (1999). See, for example, Adler, Nancy E., and Joan M. Ostrove "Socioeconomic Status and Health: what We Know and What We Don't" pp. 3-15.
"Abstract: In the past 15 years, we have seen a marked increase in research on socioeconomic status (SES) and health. Research in the first part of this era examined the nature of the relationship of SES and health, revealing a graded association; SES is important to health not only for those in poverty, but at all levels of SES. On average, the more advantaged individuals are, the better their health. . . . In the most recent era, researchers are increasingly exploring the mechanisms by which SES exerts an influence on health. There are multiple pathways by which SES determines health; a comprehensive analysis must include macroeconomic contexts and social factors as well as more immediate social environments, individual psychological and behavioral factors, and biological predispositions and processes."

Health Affairs, Vol. 21, Number 2 (2002). See, for example, Deaton, Angus, "Policy Implications of  the Gradient of Health and Wealth" pp. 13-30.
"Abstract: Men in the United States with family incomes in the top 5 percent of the distribution in 1980 had about 25 percent longer to live than did those in the bottom 5 percent. . . . I argue that the existence of the gradient strengthens the case for income redistribution in favor of the poor but that targeting health inequalities would not be sound policy."

Federal Reserve survey of level and changes of family economic conditions (2003)   The Federal Reserve Board and the regional banks research various economic conditions.