Temporal and Geographic Trends in the Global Stroke Epidemic

Abstract

Stroke continues to present a significant public health challenge for the United States. Stroke is a leading cause of adult disability1; race-ethnic and geographic disparities in stroke incidence and outcomes have remained stubbornly persistent,2 and the total number of deaths from stroke is projected to increase in the coming decades as the population ages.3 However, there is also reason for optimism. During the last 40 years, there has been a >60% decline in the age-adjusted mortality rate from stroke in the United States,4 and stroke has recently moved from its prior position as the third leading cause of death to become the fourth leading cause of death overall.5 Although there are multiple factors to help to explain this trend, improvements in blood pressure control at the population level are likely to be playing a major role. During the last few decades, each successive national health survey has recorded improvements in population systolic blood pressure and hypertension control. For example, the median systolic blood pressure among aged 60 to 74 years in 1960–1962 was ≈150 mm Hg.6 In subsequent surveys, the median systolic blood pressure has consistently declined and by the 1988–1991 National Health and Nutrition Examination Survey III, the median systolic blood pressure had decreased to 130 mm Hg.6 Improvements in blood pressure have been particularly pronounced among those with very high blood pressure, which confers a disproportionately higher risk for stroke. For instance, during the same period, the 90th percentile for systolic blood pressure decreased from >190 mm Hg to <160 mm Hg.6 This pattern of improved hypertension control has also been demonstrated in other high-income countries, which have experienced a 42% decrease in stroke incidence overall during the past 40 years.7 From the global prospective, the outlook for …