The differences between life expectancies for black people and white people indicate deeper social inequalities between races in the US.
"Prior studies in the United States have shown that, for the nation as a whole, the difference in life expectancy between blacks and whites has declined over the past 2 decades," says Sam Harper, of the Department of Epidemiology, Biostatistics & Occupational Health in the Faculty of Medicine at McGill University in Montreal, Canada.
"What was not known was how individual states have fared in reducing this gap."
Harper and colleagues wanted to see how different states have performed over the last 20 years. To do this, they used "novel statistical techniques," data from death certificates and estimates of state populations to calculate life expectancies on a state-by-state basis.
Although Medical News Today did not have access to the full figures at time of publication, Harper says that some states had performed much better than others.
The state that by far showed the largest improvement in reducing the black-white gap was New York. Wisconsin, on the other hand, exhibited a widening gap in life expectancy between black and white people.
The team knows from previous work that fewer deaths from HIV/AIDS and homicide contributed to a boost in life expectancy in New York. Harper suggests that other states may benefit from a detailed study examining how the life expectancy gap in New York decreased so much.
"Other states with comparatively large black populations like California and Texas kept the national gap from closing more than it did," Harper says.
"More generally, we found that states in the northeast made considerably more progress than states in the west for both men and women, but even within regions of the US there was a lot of heterogeneity among states," he says.
Life expectancy differences are 'longstanding public health concern'
The study acknowledges that differences in life expectancy between black and white people have been a longstanding public health concern in the US. These differences are believed to signpost deeper inequalities between races in society.
"We want to know how to reduce these differences. Given that many social and health policies are implemented at the state level, looking at how specific states have fared can provide important clues for addressing these health inequalities. Our results should be of particular interest to state public health officials focused on reducing racial differences in health."
In 2013, the Centers for Disease Control and Prevention (CDC) published a report breaking down life expectancy by state. The CDC found that life expectancies were more favorable for white people than black people in every state except for Nevada and New Mexico. Iowa exhibited the largest life expectancy difference between white and black people, at 7.8 years.
More generally, in the CDC report, Hawaii had the greatest life expectancy, with citizens living in good health from the age of 65 for an average of 17.3 years for women and 15 years for men, while Mississippi had the worst life expectancy, with an average of 11.4 years of good health from age 65 for women and 10.1 years for men.
Overall, the CDC report found that life expectancy was greater for women than it was for men. The authors of the report suggest that living environments, lifestyle behaviors and access to good health care were the most influential variables on life expectancy across states.