Incidence of stroke and stroke subtypes in Malmo, Sweden, 1990-2000 - Marked differences between groups defined by birth country

Background and Purpose-The proportion of immigrants has increased in Sweden markedly during the last decades, as in many other Western countries. Incidence of stroke has increased during this period. However, it is primarily unknown whether incidence of stroke and stroke subtypes in Sweden is related to country of birth. Methods-Incidence of first-ever stroke was followed during 10 years in a cohort consisting of all 40- to 89-year-old inhabitants in the city of Malmo, Sweden (n=118134). Immigrants from 12 different countries were compared with native-born Swedes. Results-Adjusted for age, sex, marital status, and socioeconomic indicators, the incidence of stroke ( all subtypes) was significantly higher among immigrants from former Yugoslavia (relative risk [RR], 1.31; 95% CI, 1.1 to 1.6) and Hungary (RR, 1.33; CI, 1.02 to 1.7). A significantly increased incidence of intracerebral hemorrhage was observed in immigrants from Peoples Republic of China or Vietnam (RR, 4.2; CI, 1.7 to 10.4) and the former Soviet Union ( RR, 2.7; CI, 1.01 to 7.3). Immigrants from Finland had a significantly higher incidence of subarachnoid hemorrhage (RR, 2.8; CI, 1.1 to 6.8). A significantly lower incidence of stroke was observed in the group from Romania (RR, 0.14; CI, 0.04 to 0.6). Immigrants from Denmark, Norway, Germany, Chile, Czechoslovakia, and Poland had approximately the same risk as citizens born in Sweden. Conclusions-In this urban population from Sweden, there are substantial differences in stroke incidence and stroke subtypes between immigrants from different countries. To what extent this could be accounted for by exposure to biological risk factors remains to be explored.