From Sea to Shining Sea

See related article, pages 2221–2227. Despite clear documentation that the “Stroke Belt” has existed for more than 60 years, we know remarkably little regarding the underlying causes. The US vital statistics system requiring the mandatory reporting of causes of death has provided nearly all of what we know about geographic disparities in stroke with virtually no data available on geographic disparities in stroke incidence. The vital statistics system allows estimates of stroke mortality rates to be made at the national level as well as for specific regions (eg, state and county level) and for specific race/sex groups. Large cohort studies, including Framingham,1 Atherosclerosis Risk in Communities (ARIC),2 Cardiovascular Health Study (CHS),3 and the Multi-Ethnic Study of Atherosclerosis (MESA),4 provide stroke incidence data; however, these outstanding studies are limited to only a few communities and provide little insight to the geographic variations in incidence. The National Health and Nutrition Examination Survey (NHANES) provides incidence data from a larger number of communities; however, even this study is limited in both the number of communities across the United States (only 81) and a sample size of only approximately 6000 individuals of ages where stroke is more prevalent.5 Although most readers of Stroke are likely aware of the Stroke Belt, they may not be aware of the paucity of data to address the next logical questions such as “Is the Stroke Belt caused by a higher incidence of stroke or a higher case fatality following stroke?”The lack of data describing the geographic disparities in stroke incidence underscores the substantial contribution of the article by Rich et al based on up to 22.5 years of follow up of a national cohort that provides a description of regional variations in stroke incidence.6 This important contribution is among the …