TUESDAY, April 22 (HealthDay News) -- Contrary to popular belief, life expectancies are not rising steadily and uniformly across the United States.

In fact, new research shows that between 1983 and 1999, death rates for women went up in many poor counties and, overall, geographical and racial disparities in life expectancy have worsened across the country.

"Disparities are going up not because people are getting better and some are getting better faster," said Majid Ezzati, an associate professor of international health at the Harvard School of Public Health in Boston. "The worst off are simply not getting better, and some are getting worse, and this is especially the case for women. One out of five females' health has not gotten better and, for a subset of those, mortality has gotten worse."

Ezzati is lead author of a new study in the April issue of PLoS Medicine.

It's the health-care version of the rich getting richer and the poor getting poorer.

"The poorest subgroups of the population, minorities and blacks and Hispanics in particular, are facing not just greater disparities in life chances than the rest of the population but may actually live shorter lives than they have in the past," said Dr. S. Jay Olshansky, a professor of public health at the University of Illinois, Chicago, and senior research scientist at the University of Chicago's Center on Aging. "That should be nothing less than alarming, and it points to the rather urgent need for efforts to combat problems associated with diabetes, with obesity."

Olshansky predicted such an occurrence three years ago, one which has been verified by recent research that now includes this latest study.

Between 1960 and 2000, average life expectancy in the United States increased by more than seven years for men and more than six years for women. In fact, life expectancy rates hit an all-time high in 2005, at nearly 78 years.

But national data often masks disparities at the local level. For example, for the period between 1997 and 2001, the highest and lowest life expectancies in the United States by county were 18.2 and 12.7 years apart for males and females, respectively, compared to gaps of 6.7 and 4.9 years between whites and blacks. Counties are the smallest level for which death rates are available.

Using U.S. mortality statistics for every year between 1961 and 1999, the researchers found that overall life expectancy rose from 67 to 74 years for men and from 74 to 80 years for women. From 1961 to 1983, death rates for both men and women fell, largely because of gains in cardiovascular disease.

From 1961 to 1983, the differences in death rates across different counties also fell. But beginning in the early 1980s, the differences in county-level death rates began to increase while life expectancy decreased in many counties, especially among women. Not only did differences decrease, death rates actually increased in some areas.

Most of these were counties lining the Mississippi River in the Deep South and in Appalachia, along with parts of the Midwest and Texas. The increase in death rates came from an increase in cancer, diabetes, COPD (chronic obstructive pulmonary disease) and fewer gains in cardiovascular disease. For men, add HIV/AIDS and homicide.

And the increase in disparities primarily occurred in the worst-off segment of the population, with life expectancy for 4 percent of males and 19 percent of females either declining or stagnating.

"Over the past two decades, life expectancy has actually declined in dozens and dozens of counties throughout the U.S., mostly in poor, rural areas. Since life expectancy has continued to improve in more affluent areas, this trend has nothing to do with the limits of human survival, but rather with disparities in education, employment, social services and health care," said Dr. David L. Katz, director of the Prevention Research Center at Yale University School of Medicine. "At some point, human life expectancy will cease rising for us all, because we will have reached the natural limits of our life span. But right now, what we see is a wedge of social inequities driving apart the survival experiences of different parts of our country. Removing that wedge, and narrowing the survival gap, is clearly a public health priority of the first order."

More information

The U.S. Centers for Disease Control and Prevention has more on health disparities.

SOURCES: Majid Ezzati, Ph.D., associate professor, international health, Harvard School of Public Health, Boston; David L. Katz, M.D., director, Prevention Research Center, Yale University School of Medicine, New Haven, Conn.; S. Jay Olshansky, Ph.D., professor, public health, University of Illinois, Chicago, and senior research scientist, Center on Aging, University of Chicago; April 2008, PLoS Medicine

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