A sharp decline in deaths from malnutrition and diseases like measles and tuberculosis has caused a shift in global mortality patterns over the past 20 years, according to a new report, with far more of the world’s population now living into old age and dying from diseases more associated with rich countries, like cancer and heart disease.
The shift reflects improvements in sanitation, medical services and access to food throughout the developing world, as well as the success of broad public health efforts like vaccine programs. The results are dramatic: infant mortality has declined by more than half between 1990 and 2010, and malnutrition, the No. 1 risk factor for death and years of life lost in 1990, has fallen to No. 8.
At the same time, chronic diseases like cancer now account for about two out of every three deaths worldwide, up from just over half in 1990. Eight million people died of cancer in 2010, 38 percent more than in 1990. Diabetes claimed 1.3 million lives in 2010, double the number in 1990.
But while developing countries made big strides – the average age of death in Brazil and Paraguay, for example, jumped to 63 in 2010, up from 28 in 1970 – the United States stagnated. American women registered the smallest gains in life expectancy of all high-income countries between 1990 and 2010. The two years of life they gained was less than in Cyprus, where women gained 2.3 years of life, and Canada, where women gained 2.4 years. The slow increase caused American women to fall to 36th place in the report’s global ranking of life expectancy, down from 22nd in 1990.
“It’s alarming just how little progress there has been for women in the United States,” said Christopher Murray, director of the Institute for Health Metrics and Evaluation, a health research organization financed by the Bill and Melinda Gates Foundation at the University of Washington that coordinated the report. Rising rates of obesity among American women and the legacy of smoking, a habit women in this country formed later than men, are among the factors contributing to the stagnation, he said.
The World Health Organization issued a statement Thursday saying that some of the estimates in the report differ substantially from those done by United Nations agencies, though others are similar. All comprehensive estimates of global mortality rely heavily on statistical modeling because only 34 countries – representing about 15 percent of the world’s population – produce quality cause-of-death data.
Health experts from more than 300 institutions contributed to the report, which measured disease and mortality for populations in more than 180 countries. It was published Thursday in the Lancet, a British health publication.
The one exception to the trend was sub-Saharan Africa, where infectious diseases, childhood illnesses and maternal causes of death still account for about 70 percent of all illness. In contrast, they account for just one-third in South Asia, and less than a fifth in all other regions. Sub-Saharan Africa also lagged in mortality gains, with the average age of death there rising by fewer than 10 years from 1970 to 2010, compared with a more than 25-year increase in Latin America, Asia and North Africa.
The change means that people are living longer, an outcome that public health experts praised. But it also raises troubling questions. Behavior affects people’s risks of developing noncommunicable diseases like cancer, heart disease and diabetes, and public health experts say it is far harder to get people to change their ways than to administer a vaccine that protects children from an infectious disease like measles.
“Adult mortality is a much harder task for the public health systems in the world,” said Colin Mathers, a senior scientist at the World Health Organization in Geneva. “It’s not something that medical services can address as easily.”
