Ethnicity and stroke : beware of the fallacies.

Abstract

The role of ethnicity in stroke has been the subject of a considerable number of published reports. A quick Medline search detected 454 citations on “ethnicity and stroke,” 386 on “stroke in blacks,” 251 on “stroke in African Americans,” and 74 on “stroke in Hispanics,” of which only a few can be mentioned here.1 2 3 4 5 6 7 8 9 10 11 12 There even exists a journal dedicated to ethnicity and health.13 However, the assumption that ethnicity is an isolated epidemiological variable delineating clinically distinct disease subgroups is controversial.14 15 16 17 The very concept of the word may be confounded with race (“black”), a common language or culture (“Hispanic”), a shared geographic origin (“Asian”), or a presumed common descent with diffuse boundaries (“Caucasian”). Ethnic categories are usually not defined in scientific reports, which results in dubious findings that are difficult to compare.18 The idea that a socially defined variable may reveal biological differences is fallacious, leading dangerously to biological determinism.15 For example, the genetic variation between races, traditionally classified on phenotype, is only slightly greater (10%) than that between nations (6%), and much larger within a local population (84%).18 19 Moreover, the genes responsible for skin color are few and are not associated with genetic markers for disease.14 Ethnicity as a variable may be too greatly influenced by cultural attitude and therefore biased. In the past, this attitude led to the entire invention of diseases on the basis of race. At a time when the genetic …