In 1991, the World Bank and the World Health Organization launched the Global Burden of Disease Study.  A recent article reviews the key findings (NEJM 2013; 369: 448-57).

The goals of the study are to compare the burden of one disease with others; as such, it is “necessary to consider the age at death and life expectancy of persons affected by each disease and to take account of the degree of disability (eg. discomfort, pain, or functional limitations.”  A comprehensive measure of disability, disability-adjusted life-years or DALYs, was used for comparisons.

The study examined 291 types of diseases and injuries as well as 67 risk factors in 187 countries, looking at the years 1990, 2005, and 2010.

Findings:

• In 2010, there were 2482 million DALYs which is a decrease of 0.6% from 1990.  On the basis of population growth, DALYs would have increased by 37.9% without improvements in disease burden.
• Major causes of death in 2010: Ischemic heart disease-far ahead #1 (21.1% of deaths, 7850 thousand DALYs), Stroke (6.5% of deaths, 2574 thousand DALYs), Lung/airway cancer (6.1% of deaths, 3033 thousand DALYs), Alzheimer’s (5.9% of deaths, 2022 thousand DALYs), COPD (5.8% of deaths, 3659 thousand DALYs).
• Global DALYs in 2010 (top ten -starting with #1): Ischemic heart disease, Lower respiratory tract infections, stroke, diarrhea, HIV-AIDs, Malaria, Low Back pain, Preterm birth complications, COPD, and road-traffic injury.
• Top risk factors (starting with #1): High blood pressure, tobacco smoking (including 2nd-hand smoke), household air pollution, diet low in fruit, alcohol use, high body-mass index, high fasting plasma glucose level, childhood underweight, exposure to outside pollution, physical inactivity, diet high in sodium

Since 1990, there has been a shift.  “In general, communicable, maternal, neonatal, and nutritional conditions decreased in absolute terms.”  The main exceptions were HIV and malaria. Noncommunicable diseases, especially diabetes, have been increasing in terms of percentage and absolute numbers.

Another important change has been a relative increase in disability compared with premature death.  In addition, of the “top 25 causes of years lived with disability, only COPD, diabetes, road-traffic injury, ischemic heart disease, and diarrhea are also among the tope 25 causes of years of life lost.”  “What ails most persons is not necessarily what kills them.”

Bottom-line: While collecting this type of data has many potential limitations, the broad picture it provides should help inform policymakers with priorities for research and intervention.  This data also allows the US to benchmark its efforts compared to other countries.  For example, according to the authors, currently the US has the best global performance with respect to stroke and the worst with respect to lung cancer and Alzheimer’s disease; however, “data and analyses are lacking to elucidate the drivers of these changes in relative performance.”