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 more than half in 1990. Eight million people died of cancer in 2010, 38 per cent more than in 1990.
Diabetes claimed 1.3 million lives in 2010, double the number in 1990.
“The growth of these rich-country diseases, like heart disease, stroke, cancer and diabetes, is in a strange way good news,” said Ezekiel Emanuel, chairman of the Department of Medical Ethics and Health Policy at the University of Pennsylvania.
“It shows that many parts of the globe have largely overcome infectious and communicable diseases as a pervasive threat, and that people on average are living longer.”
In 2010, 43 per cent of deaths in the world occurred at age 70 and older, compared with 33 per cent of deaths in 1990, the report said.
And fewer child deaths have brought up the mean age of death, which in Brazil and Paraguay jumped to 63 in 2010, up from 30 in 1970, the report said. The measure, an average of all deaths in a given year, is different from life expectancy and is lower when large numbers of children die.
The World Health Organization issued a statement last week saying that some of the estimates in the report differ substantially from those done by UN agencies, although others are similar.
All comprehensive estimates of global mortality rely heavily on statistical modelling because only 34 countries — representing about 15 per cent of the world’s population — produce quality cause-of-death data.
Health experts from more than 300 institutions contributed to the report, which provided estimates of disease and mortality for populations in more than 180 countries.
It was published Thursday in the Lancet, a British health publication. Sub-Saharan Africa was an exception to the trend.
Infectious diseases, childhood illnesses and maternity-related causes of death still account for about 70 per cent of the region’s disease burden, a measure of years of life lost due to premature death and to time lived at less than full health.
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 here rising by fewer than 10 years from 1970 to 2010, compared to 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.
Behaviour affects people’s risks of developing non-communicable 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.”
Tobacco use is a rising threat, especially in developing countries, and is responsible for almost six million deaths a year globally. Illnesses like diabetes are also spreading fast.