Stroke is a leading cause of disability and mortality throughout the world.[3,4] According to the World Health Organization (WHO), stroke kills approximately 4.6 million people (9 percent of all deaths) each year, and ranks as the second most common cause of mortality worldwide. The 1996 Global Burden of Disease study revealed that cardiac and cerebral vascular diseases have surpassed infectious and parasitic diseases to become the leading causes of death in the developing world, India and sub-Saharan Africa excepted.[ 5] In the People's Republic of China (PRC) alone, more than 1 million people die from stroke each year—three times the number of those who die from ischemic heart disease in that country.
Among men and women aged 30–69, cardiac and cerebral vascular diseases cause three times as many deaths worldwide as infectious and parasitic diseases. This age group generally comprises the most economically productive members of the workforce, a situation that serves to amplify the toll of death and disability associated with stroke and related disorders.[ 2,7] In South Africa, for example, stroke accounts for between 8 and 10 percent of all reported deaths and 7.5 percent of deaths among people of prime working age, 25 to 64 years old.
Table 10-1 lists several additional reports describing stroke mortality in diverse populations. While the wide range of mortality rates shown may to some extent reflect population differences in exposure to risk factors for stroke (as discussed further below), the variation probably results as well from methodological differences among studies.[ 9] For example, in sub-Saharan Africa, most data on stroke mortality have been hospital-based, although the majority of stroke deaths in that region are thought to occur at home. Box 10-1 describes an attempt to take this situation into account and produce more accurate measures of stroke mortality in urban and rural Tanzania.
Some studies in developing countries have found significant geographic  and ethnic [12,13] variations in stroke mortality within the same nation.[14,15] Other researchers, however, point out that such results need to be interpreted with caution as no standards exist for classifying ethnic groups. Comparative data for more than 30 countries from 1950 to 1990 show increasing mortality from stroke in Eastern Europe, contrasting with declines seen in the United States; Europe; and Argentina, Chile, Uruguay, and Venezuela.
In addition to causing early death, stroke results in significant nonfatal illness and disability. In the 1996 Global Burden of Disease study, stroke ranked as the sixth leading cause of lost years of healthy life and was responsible for about 2.4 percent of disability-adjusted life years (DALYs) worldwide. Projections for 2020 place cerebrovascular disease—a more general term that describes any abnormality