AIDS, smoking and obesity are reversing progress made in helping people live longer around the world, with mortality rates worsening over the past 20 years in 37 countries, researchers reported on Thursday.
They found Icelandic men have the lowest risk of premature death, while Cypriot women do. Some rich countries such as the United States and Britain scored relatively poorly, the survey found.
In most places, men have twice the relative mortality rate of women, Dr. Christopher Murray of the University of Washington in Seattle and colleagues reported in the Lancet medical journal.
"Worldwide, the 1990s reversal in the trend in adult mortality is probably a result of the HIV pandemic and the sharp rise in adult mortality in countries of the former Soviet Union," the researchers wrote.
"One of the most striking patterns is the rapid decline in adult female mortality in south Asia; in 1970 this was the region with the highest risk of female mortality and by 2010, (the risk of dying before age 60) had fallen by 56 percent."
Murray and colleagues used a complex formula to calculate the probability that someone aged 15 will die before they reach 60. They believe their method paints a more accurate picture than methods used by the United Nations, and can be used to compare countries with populations of different ages.
In the 40 years since 1970, they found, adult mortality risk fell by 34 percent among women and 19 percent in men globally.
But some places had notable reversals in rank, including the former Soviet Union. Russia has fallen from 43rd place for female mortality in 1970 to 121st.
"Research shows that across countries, inequality in adult mortality has grown to the point where adult men in Swaziland — the country with the worst mortality rate — now have a probability of premature death that is nine times the mortality rate of the best country, Cyprus," Murray's team wrote.
The United States, where 60 percent of adults are overweight or obese, fell in overall rankings, from 34th in the world in female mortality and 41st in male mortality in 1990 to 49th for women and 45th for men in 2010 — behind Chile, Tunisia, and Albania.
But mortality rates fell 50 percent over the same time in South Korea.
Murray said he wanted to study adult mortality globally because so much emphasis goes into helping very young children survive.
"Every year, more than 7.7 million children die before their fifth birthday; however, over three times that number of adults — nearly 24 million — die under the age of 60 years," his team wrote.
"The prevention of premature adult death is just as important for global health policy as the improvement of child survival."
According to the United Nations, 8.8 million children under the age of 5 died in 2008.