Researcher Alan Lopez, PhD, and colleagues combed through thousands of data sources from all over the globe on 136 diseases and injuries in 2001.
Lopez works in Brisbane, Australia at the University of Queensland's School of Population Health. He and his colleagues published the results in The Lancet. Among their findings:
- Slightly more than 56 million people died in 2001.
- Those deaths included 10.6 million children, almost all of whom (99%) lived in low- and middle-income countries.
- More than half of the children died from 5 preventable or treatable conditions:
- HIV/AIDS in Africa and setbacks in health for the former Soviet Union offset gains against other diseases.
The study shows that one in three deaths was due to communicable diseases, nutritional deficiencies, and health problems in pregnant women, new mothers, fetuses, or newborns.
Top 10 Causes of Death
However, other leading causes of death differed depending on countries' incomes. Here is the list for high-income countries:
- Heart disease
- Lung cancer
- Lower respiratory infections
- Chronic obstructive pulmonary disease (COPD)
- Colon and rectum cancers
- Alzheimer's disease
- Type 2 diabetes
- Breast cancer
- Stomach cancer
Here is the list for low- and middle-income countries:
Lopez and colleagues saw some gains and setbacks, compared to the study's 1990 findings.
"Worldwide, HIV/AIDS and malaria are large and growing causes of death and disease burden, especially in sub-Saharan Africa," the researchers write, adding that the records show some progress in Africa against measles, acute respiratory infections, and diarrhea.
They also note that countries of the former Soviet Union had "setbacks" in adult deaths during the 1990s. The study doesn't show a reason for that pattern, but the "absence of sustained health monitoring and policies" in those countries may have played a role, the researchers note.
They add that while health records have improved in some parts of the world, some countries have more detailed records than others.