The Adelaide Stroke Incidence Study (ASCEND) was

One of the greatest healthcare challenges of the 21st century is the global aging population.1 Although the incidence of stroke has been declining in the developed world during the past 30 years, population aging threatens to increase total stroke incidence and the burden of poststroke disability. One prediction, calculated from the age-specific stroke incidence reported in international studies, suggested that the world-wide total stroke burden would increase 5-fold from 13 mil-lion disability-adjusted life years in the 1990s to 68 million disability-adjusted life years by 2020.2 However, age-specific stroke incidence rates may be declining sufficiently to com-pensate for changing demographics. Indeed, serial popula-tion stroke studies conducted during the past 3 decades have demonstrated decreasing stroke incidence despite increasing population age.3 Increasing stroke burden is not an inevitable consequence for an aging population if primary prevention strategies are targeted to stroke incidence patterns