The gap between counties with the highest and lowest life expectancies is larger now than it was in 1980 - a more than a 20-year difference in 2014 - highlighting massive and growing inequality in the health of Americans.
Oglala Lakota County, South Dakota, a county that includes the Pine Ridge Native American reservation, had the lowest life expectancy in the country in 2014 at 66.8 years, comparable to countries like Sudan (67.2), India (66.9), and Iraq (67.7).
Clusters of counties with low life expectancies were also identified in Kentucky, West Virginia, Alabama, and several states along the Mississippi River. Several counties in these states and others saw decreases in life expectancy since 1980, while much of the country experienced increases.
However, a cluster of counties in Colorado had the highest life expectancies in the US, with Summit County topping the list at 86.8 years, followed by Pitkin County (86.5) and Eagle County (85.9). By comparison, at the country level, Andorra had the highest life expectancy in the world that same year at 84.8, followed by Iceland at 83.3.
These findings demonstrate that policy changes at all levels are needed to reduce inequality in the health of Americans, said Ali Mokdad, an author on the study by the Institute for Health Metrics and Evaluation (IHME) at the University of Washington in Seattle, who leads US county health research at IHME. “Federal, state, and local health departments need to invest in programmes that work and engage their communities in disease prevention and health promotion,” Mokad said.
In the study the authors calculated life expectancy by county from 1980 to 2014. They also examined the risk of dying among five age groups, as well as the extent to which risk factors, socioeconomics and race, and health care contribute to inequality.
“Looking at life expectancy on a national level masks the massive differences that exist at the local level, especially in a country as diverse as the US. Risk factors like obesity, lack of exercise, high blood pressure, and smoking explain a large portion of the variation in lifespans, but so do socioeconomic factors like race, education, and income,” said lead author Laura Dwyer-Lindgren, a researcher at IHME.
‘Inequalities in life expectancy among US counties, 1980 to 2014,’ JAMA Internal Medicine, 8 May, 2017.
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