Data from the Global Burden of Disease Study 2013 suggest that global life expectancy has increased by 5.8 years among men and 6.6 years among women from 1990 to 2013.
Some causes of death, however, have seen increased rates in that time, according to the data published in The Lancet. The most significant increase is in the rate of death from liver cancer caused by hepatitis C, which has increased by 125%. Other increases in mortality rates include atrial fibrillation and flutter by 100%; drug use disorders by 63%; chronic kidney disease by 37%; sickle cell disorders by 29%; diabetes by 9% and pancreatic cancer by 7%.
Also of note is the one region where life expectancy has decreased: southern sub-Saharan Africa, where deaths related to HIV/AIDS have decreased by 5 years. Worldwide, deaths from HIV/AIDS have declined every year since 2005, but it is still the greatest cause of premature death in 20 countries in sub-Saharan Africa.
“The progress we are seeing against a variety of illnesses and injuries is good, even remarkable, but we can and must do even better,” Christopher Murray, MD, professor of global health at the University of Washington, said in a press release. “The huge increase in collective action and funding given to the major infectious diseases such as diarrhea, measles, tuberculosis, HIV/AIDS and malaria has had a real impact. However, this study shows that some major chronic diseases have been largely neglected but are rising in importance, particularly drug disorders, liver cirrhosis, diabetes and chronic kidney disease.”
That data include the most recent estimates of the number of yearly deaths related to 240 different causes throughout 188 countries. In high-income regions, the 15% lower rate of death related to most cancers and the 22% lower rate of death due to cardiovascular diseases have contributed to the increased life expectancy. In low-income countries, there were significantly declining rates of death related to diarrhea, lower respiratory tract infections and neonatal disorders, which has led to extended life expectancy.
The 10 leading causes of premature death have not changed significantly. HIV/AIDS joined the list as the sixth leading cause of death worldwide, but tuberculosis was bumped from the top 10. Ischemic heart disease is the leading cause of death worldwide, followed by lower respiratory infections, cerebrovascular disease and diarrheal diseases. Malaria is the eighth leading cause of death worldwide.
There has been a significant decline in deaths among children aged 1 to 59 months: 7.6 million in 1990 to 3.7 million in 2013. However, respiratory tract infections, malaria and diarrheal disease are still in the top five causes of death for children, and are responsible for almost 2 million deaths annually.
In an accompanying commentary, Igor Rudan, PhD, and Kit Yee Chan, PhD, of the Centre for Population Health Sciences and Global Health Academy at the University of Edinburgh Medical School in Scotland, said that estimates of disease and death are necessary to guide investment decisions that could help save lives. They also said the responsibility for these estimates has typically rested with WHO.
“Although WHO’s team of experts have been doing fine technical work for many years, its monopoly in this field had removed incentives to invest more time and resources in continuous improvement,” they wrote. “The emergence of the Institute for Health Metrics and Evaluation, generously supported by the Bill & Melinda Gates Foundation, has changed the science of global health metrics in a similar way to Celera Genomics’ competition with the Human Genome Project.
“The competition between WHO and the Global Burden of Disease study has benefited the entire global health community, leading to converging estimates of the global causes of death that everyone can trust.”
For more information:
Global Burden of Disease Study 2013 Mortality and Causes of Death Collaborators. Lancet. 2014;doi:10.1016/S0140-6736(14)61682-2.
Rudan I. Lancet. 2014;doi:10.1016/S0140-6736(14)62006-7.
Disclosure: See the study for a full list of relevant financial disclosures. Chan and Rudan report no relevant disclosures.