Incidence of stroke and stroke subtypes in Malmö, 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 Malmö, Sweden (n=118,134). 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.

Risk factors for intracerebral and subarachnoid hemorrhage among Hispanics and non-Hispanic whites in a New Mexico community.

BACKGROUND AND OBJECTIVE: A higher incidence of spontaneous intracerebral and subarachnoid hemorrhage among Hispanics than non-Hispanic whites has been measured in Bernalillo County, New Mexico. In an attempt to explain these differences, we compared historical vascular risk factors between Hispanics and non-Hispanic whites living in this community. METHODS: An ongoing telephone survey, the Behavioral Risk Factor Surveillance System, collected annual data about vascular risk factors among non-institutionalized, randomly selected adults. Data covering 6 years, 1988-1993, were analyzed. RESULTS: There were 843 Hispanic and 1,635 non-Hispanic white residents of Bernalillo County, New Mexico, who participated in this survey. Because Hispanics were significantly younger than non-Hispanic whites (37.7 vs. 43.4 years, p < 0.001), all other comparisons were adjusted for age. Prevalence of hypertension was similar between these ethnic groups (15-17%). Prevalence of alcohol drinking considered risky for abuse was similar between these ethnic groups (5-6%), but was significantly higher among Hispanic men than women (8.5 vs. 1.6%, p < 0.001). The quantity of alcohol consumption among those at risk for abuse was similar between these ethnic groups. Prevalence of current cigarette smoking was similar between these ethnic groups (22-23%), but Hispanics smoked significantly less than non-Hispanic whites (11.4 vs. 15.2 cigarettes per day, p < 0.001) and among non-Hispanic whites, men smoked significantly more than women (17.0 vs. 13.4 cigarettes per day, p = 0.001). CONCLUSION: The vascular risk factors which we compared between Hispanics and non-Hispanic whites do not help to explain the higher incidence of hemorrhagic strokes among the Hispanics in Bernalillo County, New Mexico. Additional risk factors for hemorrhagic strokes in these two ethnic groups should be studied.

Incidence of spontaneous subarachnoid hemorrhage among Hispanics and non-Hispanic whites in New Mexico.

BACKGROUND AND PURPOSE: There are differences in cerebrovascular disease incidence between racial and ethnic groups. Little is known about cerebrovascular disease among Hispanics living in the southwestern United States as compared to non-Hispanic whites. This is the first study which measures and compares the incidence of spontaneous subarachnoid hemorrhage (SAH) among Hispanics and non-Hispanic whites living in Bernalillo County, New Mexico. This information may help reduce the risk and incidence of SAH. METHODS: Medical records of all possible cases of spontaneous SAH occurring during a two-year period (January 1, 1993 to December 31, 1994) among residents of Bernalillo County, New Mexico, were reviewed in all local hospitals. Hospital records were identified by ICD-9-CM codes. Medical examiner records were also reviewed for additional SAH cases occurring during the same time period. The 1990 U.S. census provided the population base. RESULTS: There were 22 spontaneous SAHs among 267,965 non-Hispanic whites and 25 spontaneous SAHs among 178,310 Hispanics. Incidence of SAH increased with age in both groups. The age- and sex-adjusted total annual incidence of SAH per 100,000 people was 3.73 among non-Hispanic whites and 9.19 among Hispanics (relative risk for Hispanics 2.46, 95% confidence interval 1.37-4.43, P = 0.003). The incidence rates among men and women were not significantly different in either ethnic group. CONCLUSIONS: The incidence of SAH among Hispanic residents of Bernalillo County, New Mexico, is approximately two and a half times higher than that among non-Hispanic whites. This suggests a higher prevalence or a greater tendency to rupture of berry aneurysms among Hispanics as compared to non-Hispanic whites. The reasons for this difference require further investigation.