The List: How We Will Die in 20 Years

Everyone dies. The question is when and how. We cant help you with the when, but the World Health Organizations recently updated Global Burden of Disease report can give you a better idea of how. The study examines the leading causes of death from 2004 and, using projections of economic growth and advances in medical treatment, forecasts the leading killers in 2030. Here are three causes of death that will grow dramatically more likely, and three that might be on the way out.

RISING CAUSES:

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Heart Disease

2004: No. 1 killer with 7.2 million deaths (12.2 percent of total)

2030: No. 1 killer with 9.6 million (14.2 percent)

Prognosis: Ischemic heart disease, the most deadly form of heart disease, is characterized by reduced blood flow to the heart, usually because of constricted coronary arteries. Often caused by a lifetime accumulation of fatty deposits in the arteries, it primarily affects older people. For this reason, it has historically claimed most of its victims from the developed world, where populations are more likely to reach old age. The developing worlds population, however, is also getting older, and therefore more susceptible to noncommunicable conditions, such as heart disease and cancer, which affect people later in life. A projected rise in tobacco use during the next two decades will also help ischemic heart disease retain its status as the worlds top killer.

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Lung Disease

2004 deaths: No. 4 killer with 3.0 million deaths (5.1 percent)

2030 deaths: No. 3 killer with 5.8 million (8.6 percent)

Prognosis: With tobacco use expected to rise, particularly among men, in low- and middle-income countries, the WHO also expects a dramatic increase in cases of emphysema and chronic bronchitis, the most common types of chronic obstructive pulmonary disease (COPD). Thwarted by taxation and an increased awareness of the health risks of cigarettes in the developed world, tobacco companies have been marketing their wares in developing countries where antismoking measures are lax. Unfortunately, the long lag time between starting smoking and getting sick means that the damage the world will see in 20 years from COPD has mostly already been done.

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Traffic Accidents

2004 deaths: No. 9 killer with 1.3 million deaths (2.2. percent)

2030 deaths: No. 5 killer with 2.2 million (3.6 percent)

Prognosis: Economic growth in developing countries will result in more vehicles on the road, causing more accidents. This will be especially true in fast-growing Asia, but also in Africa and Latin America. Pedestrians and bicyclists will bear the brunt of the casualties in the developing world because they face the greatest risk on streets teeming with cars and trucks. History also tells us that developing countries rarely invest in vehicle safety, causing greater fatalities, especially among passengers on unsafe vehicles such as buses and motorcycles. Finally, developing countries also tend to skimp on enforcement of traffic laws, which leads to chaotic roads populated by untrained drivers.

DECLINING CAUSES:

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HIV/AIDS

2004 deaths: No. 6 killer with 2.0 million deaths (3.5 percent)

2030 deaths: No. 10 killer with 1.2 million (1.8 percent)

Prognosis: Previous estimates for HIV/AIDS deaths in 2004 were close to 3 million. But new studies measuring the scope of the AIDS epidemic, especially in India, persuaded scientists to revise that number down in this report. Researchers at the Joint U.N. Program on HIV/AIDS now think that in some parts of the world, notably in Africa, the epidemic has plateaued and might be starting to decline. Assuming that antiretroviral drug coverage continues to rise at current rates, AIDS deaths will likely rise to a maximum of 2.4million in 2012 before starting to decline.

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Tuberculosis

2004 deaths: No. 7 killer with 1.5 million deaths (2.5 percent)

2030 deaths: No. 20 killer with 670,000 (1 percent)

Prognosis: Recent efforts to improve TB treatment, particularly the Stop TB Partnerships directly observed treatment, short course (DOTS) program have proven remarkably successful. Under DOTS, clinicians administer the drugs to patients and then ask that they be taken on the spot, reducing the risk that patients will stop treatment due to nasty side effects. The program still suffers from a significant funding gap, with the Stop TB Partnership estimating it will require an additional $31 billion to expand DOTS treatment to all those in need. According to the WHO, sub-Saharan Africa still has the greatest number of TB cases, though the disease is spreading fastest in Southeast Asia.

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Diarrheal Disease

2004 deaths: No. 5 killer with 2.2 million deaths (3.6 percent)

2030 deaths: No. 23 killer with 710,000 (0.9 percent)

Prognosis: Diarrheal diseases are caused by the bacteria, viruses, and parasites to which children, especially those without access to clean drinking water and proper sanitation, are particularly susceptible. The worlds rapidly graying population means that a smaller proportion will be at risk from such illnesses. Economic growth, which leads to cleaner living conditions and better medical care, will also help reduce the number of children affected. Diarrheal diseases will remain a pest, however. They are by far the most common illnesses in the world, accounting for more than 4.6 billion cases per year.