BOSTON -- In matters of life and longevity, the United States is not one nation, indivisible, but eight nations divided by gender, race, income, and address, with huge differences in mortality rates.
BOSTON, Sept 12 -- In matters of life and longevity, the United States is not one nation, indivisible, but eight nations divided by gender, race, income, and address, with huge differences in mortality.
Depending on which of the eight Americas one inhabits can make the difference between the possibility of living until age 90 or dying at 55, according to an analysis of data from the U.S. Census Bureau and the National Center for Health Statistics by epidemiologists at Harvard and the University of California San Francisco.
Christopher J. L. Murray, M.D., D.Phil of the Harvard School of Public Health, and colleagues, used the two databases to calculate death rates for 1982 through 2001 by county of residence and race, they reported in the September issue of the PLoS Medicine.
They determined enormous disparities in mortality among the eight Americas. The excess mortality, they determined, begins in adolescence and continues through middle-age.
Their analysis defied the traditional public health approach of focusing interventions on children and the elderly, said Dr. Murray and colleagues.
They identified 8,221 race-county units to which they factored in gender, population density, income, and homicide rate. Those data were then reclassified as eight unique Americas, each of which may represent millions of people, the investigators
The differences among these countries are stark. For example, in 2001 a 15-year-old black girl living in high risk urban area was 3.4 times more likely to die before age 60 than a 15-year-old Asian girl living in northern New Jersey. Moreover, that 15-year-old black girl was 3.8 times more likely to die before age 45 than her Asian counterpart. For black males the risk was even higher.
On one end, Asian Americans who live in areas where Pacific Islanders make up less than 40% of the population have achieved record life-expectancy-three years better than those in Japan and four years better than in Iceland for men.
But, "tens of millions of Americans are experiencing levels of health that are more typical of middle-income or low-income developing countries," Dr. Murray and colleagues wrote.
Moreover, the mortality disparities "are most concentrated in young and middle-aged males and females, and are a result of a number of chronic diseases and injuries with well-established risk factors."
For men, life expectancy was longest in what the authors called America 1, defined as Asian America, and life was shortest in southern rural poor black America, or America 7, which was just slightly worse than the life expectancy for men in high risk urban black America.
They defined the eight Americas, or population groups, this way:
Many differences in life expectancy were found between the eight groups. As an example, in 2001the life expectancy gap between the 3.4 million high-risk urban black males and the 5.6 million Asian females was nearly 21 years. Within the sexes, the gap between the best-off and the worst-off groups was 15.4 years for males (Asians versus high-risk urban blacks) and 12.8 years for females (Asians versus low-income rural blacks in the South).
Little had changed in 14 years. The gaps between best-off and worst-off were similar in 2001 to what they were in 1987.
The authors suggested three steps to address the longevity disparities: