In the public health field, there is an ongoing debate as to whether improvement in the overall health of the population is linked to increases or decreases in social inequities in health, that is, the inequities between higher-income and lower-income groups or people of different race/ethnicities.
In the most comprehensive study to date addressing this debate, researchers at the Harvard School of Public Health (HSPH) found that, as overall health improved (as measured by a decline in mortality rates), inequities in health both shrank and widened between 1960 and 2002. The study demonstrates that the recent trend of growing U.S. disparities in health status is not inevitable.
“Our papers refutes the argument, currently gaining ground, that as overall population health improves, it is inevitable that socioeconomic disparities in health will increase, allegedly because the better-off more quickly take advantage of health-promoting resources,” said Nancy Krieger, professor of society, human development and health at HSPH and the study's lead author. “Instead, we clearly show that this argument is flawed because, in the period from 1966 to 1980, socioeconomic disparities declined in tandem with a decline in mortality rates.”
Journalists can preview the paper here: http://www.plos.org/press/plme-05-02-krieger.pdf. The study will be published in the February 26, 2008 issue of the open-access journal PLoS Medicine. At that time, the paper will be freely available here: http://medicine.plosjournals.org/perlserv/?request=get-document&doi=10.1371/journal.pmed.0050046
Krieger and her co-authors set out to test the hypothesis that health inequities widen—or shrink—in a context of declining mortality rates. Prior studies had typically gone back only to the 1980s and had found evidence chiefly of growing health disparities. The HSPH researchers looked at two measures of population health--rates of premature mortality (dying before the age of 65) and rates of infant death (dying before the age of 1)--during the period from 1960 to 2002. They measured both absolute and relative inequities. U.S. county mortality rates were ranked for different county income levels and for the total population as well as for U.S. whites and U.S. people of color.
The results showed that mortality rates declined among all county income groups. Between 1966 and 1980, absolute and relative inequities in premature mortality shrank, especially for people of color. After 1980, relative inequities increased, while absolute inequities stayed flat. The same trends were apparent for the inequities in infant death rates.