Cardiovascular disease in special populations III: stroke.

Abstract

Stroke is a sudden devastating event that, if it does not kill immediately, leaves the patient with various degrees of disability that affect physical and psychological well-being. It is the third most common cause of death in the United States. Unlike a myocardial infarction, in which the general functioning of ambulation, speech, and thought processes is left intact, stroke produces a physical and psychological dependence on caregivers, leads to a sense of isolation unlike most other cardiovascular (CV) events, and, especially in the case of special populations such as many blacks, puts a powerful strain on economic resources. In addition, there is evidence that the risk for stroke and interventions to the stroke patient in special populations may vary. Blacks, Hispanics, American Indians ⁄ Alaska Natives, and Asians have a higher mortality at younger ages than whites. In 2005, the prevalence of stroke among Native Americans (6.0%), multiracial persons (4.6%), and blacks (4.0%) was higher than whites (2.3%), with Asians and Hispanics having similar prevalence as whites. Higher educational status is also associated with a history of stroke, from 1.8% in college graduates to 4.4% in persons with less than 12 years of education. The particularly excessive burden of stroke in blacks is seen especially in the southeastern United States and in those who are relatively young (aged 35–64 years). Of stroke deaths in 2002, 12% occurred in persons younger than 65 years and the proportion of stroke deaths in this younger age group was higher among blacks, Native Americans, and Asians compared with whites. This amounted to 3400 excess strokes in blacks in this younger population compared with whites. Although mortality rates have decreased in both blacks and whites, there remains an unchanging magnitude of the excess rates in blacks compared with whites. Although the mortality from stroke in the United States per population has decreased ever since records were first kept early in the 20th century, the vast increase in population and increase in average lifespan has led to many more cases. Trends in the age-, race-, and sex-adjusted prevalence of stroke between 1971 and 1994 from the National Health and Nutrition Examination Surveys (NHANES I to NHANES III) demonstrated an increase from 1.4% to 1.9%, an average increase of 7.5%. The noninstitutionalized stroke survivor rate increased by 60% during this period, from 1.5 million to 2.4 million. As for racial differences, 5-year mean change in stroke prevalence in noninstitutionalized survivors of stroke increased by 28% in black women and 12% in white men, but decreased by 3% in black men and white women (Table I). However, in terms of number-estimated noninstitutional stroke survivors, 5-year changes in numbers of survivors increased in all groups, from an increase of 18,000 in black men to 159,000 in white men. These differences of course were accounted for by the 10-fold larger population of whites than blacks. An intriguing finding in terms of possible environmental implications is that the stroke death rate is particularly high in the southeastern United States, as previously mentioned. Geographic difference in stroke prevalence may relate to cultural differences in diet and exercise, lack of economic opportunity, and regional differences in health care and preventive services. Both environmental risk factors and new evidence for genetic determinants leading to risk for stroke in special populations have to be taken into consideration in evaluation of preventive interventions.