People are living longer but are not in best health, global study findsBMJ 2012; 345 doi: http://dx.doi.org/10.1136/bmj.e8511 (Published 14 December 2012) Cite this as: BMJ 2012;345:e8511
The biggest ever study of people’s health worldwide has found that the number of deaths of children under the age of 5 years fell by 60% between 1970 and 2010, but that of adults aged 15-49 rose by 44%, largely because of increases in violence and HIV and AIDS.
The Global Burden of Disease Study 2010, funded by the Bill and Melinda Gates Foundation and led by the Institute for Health Metrics and Evaluation at the University of Washington, involved 486 authors from 302 institutions in 50 countries and delivered 650 million results.
Publishing in an entire issue of the Lancet (http://bit.ly/XkYEvr), researchers looked at 300 diseases, injuries, and risk factors and found that there were just 50 causes for 78% of the global disease burden.1
They found that life expectancy rose in men from 56.4 years in 1970 to 67.5 in 2010 and in women from 61.2 years to 73.3 in the same period.
The contribution of different risk factors to the global disease burden has shifted remarkably in the last 20 years, away from risks for communicable diseases in children towards non-communicable diseases for adults. The three leading risk factors behind the global disease burden in 2010 were high blood pressure, tobacco smoking, and alcohol consumption. In 1990 the top three risk factors were low weight among children, household air pollution from solid fuels, and tobacco.
The number of deaths from communicable, maternal, neonatal, and nutritional causes fell by 17% from 1990 to 2010, from 15.9 million to 13.2 million. However, the number of deaths from malaria rose by an estimated 20% over the same period.
Non-communicable diseases accounted for nearly two in every three deaths worldwide in 2010, up from around one in two in 1990. Eight million people died from cancer in 2010, a rise of 38% from 1990.
Ischaemic heart disease, stroke, chronic obstructive pulmonary disease, lower respiratory infections, lung cancer, and HIV and AIDS were the leading causes of death in 2010. Ischaemic heart disease and stroke together were responsible for a quarter of deaths worldwide, up from a fifth in 1990.
Christopher Murray, director of the Institute for Health Metrics and Evaluation, said that what surprised him was the number of conditions that cause disability. In 1990 the total number of person years of life with a disability was around 583 million, compared with 777 million in 2010. The main causes of this have changed little in 20 years: low back pain, major depressive disorder, iron deficiency anaemia, neck pain, and chronic obstructive pulmonary disease.
“Health services around the world are already having to deal with these disabling conditions, and there is very little policy and very little research done in this area,” Murray said. “That’s why we want to distinguish disability from NCDs [non-communicable diseases],” he said.
Another key finding was that the changes seen globally were occurring more slowly in sub-Saharan Africa. Irene Agyepong, a specialist in public health from the University of Ghana, said that this region faced a “double burden” of a rise in non-communicable diseases while still tackling the problems of childhood and maternal mortality and communicable diseases.
“The [United Nations] millennium development goal agenda will remain relevant after 2015, but there are these new problems that are coming,” she said.
Peter Piot, director of the London School of Hygiene and Tropical Medicine, who compared the study’s publication to the sequencing of the human genome in its potential impact, said, “I’m concerned that there is a trend towards dropping the current MDGs for something that is very vague. If we drop our focus on the current MDGs that would be a disaster.”
Margaret Chan, director general of the World Health Organization, said that the study was an important milestone and that the challenge now was to close the gaps in data collection, especially in low and middle income countries, “so that we no longer have to rely heavily on statistical modelling for data on disease burden.”
Cite this as: BMJ 2012;345:e8511