Defining cause of death in stroke patients: The Brain Attack Surveillance in Corpus Christi Project

Stroke mortality is an important national health statistic and represents a frequent endpoint for epidemiologic studies. Several methods have been used to determine cause of death after stroke, but their agreement and reliability are unknown. Two hundred consecutive deaths of transient ischemic attack or ischemic stroke patients were identified (January 2000-September 2001) from an ongoing population-based stroke surveillance study in Texas, The Brain Attack Surveillance in Corpus Christi Project. Two neurologists independently recorded the cause of death based on two methods: 1) determining the underlying cause of death as defined by the World Health Organization, and 2) determining whether the death was stroke related. Kappa statistics with 95% confidence intervals were calculated by comparing agreement between methods within reviewers and between reviewers within methods. Agreement between the two cause-of-death-determination methods for each neurologist was 0.41 (95% confidence interval (CI): 0.31, 0.51) and 0.47 (95% CI: 0.38, 0.58), respectively. Agreement between neurologists for the underlying-cause-of-death method was 0.46 (95% CI: 0.32, 0.60); for the stroke-related method, it was 0.63 (95% CI: 0.52, 0.75). Accurate, reliable determinations of cause of death after stroke/transient ischemic attack are not currently feasible. More research is needed to identify a reliable process for coding cause of death from stroke.     

Excess stroke in Mexican Americans compared with non-Hispanic Whites: the Brain Attack Surveillance in Corpus Christi Project

Mexican Americans are the largest subgroup of Hispanics, the largest minority population in the United States. Stroke is the leading cause of disability and third leading cause of death. The authors compared stroke incidence among Mexican Americans and non-Hispanic Whites in a population-based study. Stroke cases were ascertained in Nueces County, Texas, utilizing concomitant active and passive surveillance. Cases were validated on the basis of source documentation by board-certified neurologists masked to subjects' ethnicity. From January 2000 to December 2002, 2,350 cerebrovascular events occurred. Of the completed strokes, 53% were in Mexican Americans. The crude cumulative incidence was 168/10,000 in Mexican Americans and 136/10,000 in non-Hispanic Whites. Mexican Americans had a higher cumulative incidence for ischemic stroke (ages 45-59 years: risk ratio = 2.04, 95% confidence interval: 1.55, 2.69; ages 60-74 years: risk ratio = 1.58, 95% confidence interval: 1.31, 1.91; ages >or=75 years: risk ratio = 1.12, 95% confidence interval: 0.94, 1.32). Intracerebral hemorrhage was more common in Mexican Americans (age-adjusted risk ratio = 1.63, 95% confidence interval: 1.24, 2.16). The subarachnoid hemorrhage age-adjusted risk ratio was 1.57 (95% confidence interval: 0.86, 2.89). Mexican Americans experience a substantially greater ischemic stroke and intracerebral hemorrhage incidence compared with non-Hispanic Whites. As the Mexican-American population grows and ages, measures to target this population for stroke prevention are critical.     

Comparison of active and passive surveillance for cerebrovascular disease: The Brain Attack Surveillance in Corpus Christi (BASIC) Project

To provide a scientific rationale for choosing an optimal stroke surveillance method, the authors compared active surveillance with passive surveillance. The methods involved ascertaining cerebrovascular events that occurred in Nueces County, Texas, during calendar year 2000. Active methods utilized screening of hospital and emergency department logs and routine visiting of hospital wards and out-of-hospital sources. Passive means relied on International Classification of Diseases, Ninth Revision (ICD-9), discharge codes for case ascertainment. Cases were validated by fellowship-trained stroke neurologists on the basis of published criteria. The results showed that, of the 6,236 events identified through both active and passive surveillance, 802 were validated to be cerebrovascular events. When passive surveillance alone was used, 209 (26.1%) cases were missed, including 73 (9.1%) cases involving hospital admission and 136 (17.0%) out-of-hospital strokes. Through active surveillance alone, 57 (7.1%) cases were missed. The positive predictive value of active surveillance was 12.2%. Among the 2,099 patients admitted to a hospital, passive surveillance using ICD-9 codes missed 73 cases of cerebrovascular disease and mistakenly included 222 noncases. There were 57 admitted hospital cases missed by active surveillance, including 13 not recognized because of human error. This study provided a quantitative means of assessing the utility of active and passive surveillance for cerebrovascular disease. More uniform surveillance methods would allow comparisons across studies and communities.     

Neighborhood environment and risk of ischemic stroke: the brain attack surveillance in Corpus Christi (BASIC) Project

The authors explored whether neighborhood-level characteristics are associated with ischemic stroke and whether the association differs by ethnicity, age, and gender. Using data from the Brain Attack Surveillance in Corpus Christi Project (January 2000-June 2003), they identified cases of ischemic stroke (n = 1,247) from both hospital and out-of-hospital sources. Census tracts served as proxies for neighborhoods, and neighborhood socioeconomic status scores were constructed from census variables (higher scores represented less disadvantage). In Poisson regression analyses comparing the 90th percentile of neighborhood score with the 10th, the relative risk of stroke was 0.49 (95% confidence interval (CI): 0.41, 0.58). After adjustment for age, gender, and ethnicity, this association was attenuated (relative risk (RR) = 0.79, 95% CI: 0.63, 1.00). There was no ethnic difference in the association of score with stroke (p for interaction = 0.79). Significant effect modification was found for age (p for interaction < 0.001) and gender (p for interaction = 0.04), with increasing scores being protective against stroke in men and younger persons. Associations were attenuated after adjustment for education (men: RR = 0.77, 95% CI: 0.55, 1.07; persons aged <65 years: RR = 0.65, 95% CI: 0.41, 1.02). Neighborhood characteristics may influence stroke risk in certain gender and age groups. Mechanisms for these associations should be examined.     

Anthropology and the study of chronic disease: adolescent blood pressure in Corpus Christi, Texas

In this anthropological study, the influence of psychosocial adaptation, and social and biological factors upon the blood pressures of Mexican-American adolescents and adolescents of European descent (Anglo-Americans) in Corpus Christi, Texas were examined. Black Americans have one of the highest rates of hypertension of any population in the world. The reasons for this are not entirely clear. Epidemiologic studies have shown that although clinically defined hypertension usually does not appear until adulthood, systematic differences in the average blood pressures of black and white history of discrimination and prejudice are in some way related to the prevalence of hypertension among black Americans, then Mexican-Americans of south Texas, who also have experienced a high rate of poverty and a history of discrimination, might also be expected to have a higher rate of hypertension than other Americans. Mexican-American youths were found to have a significantly higher mean systolic pressure than Anglo youths. Mexican-Americans also were found to have significantly more problematic psychosocial adaptation. There was little relationship, however, between problematic psychosocial adaptation and high blood pressure. Subsequent statistical analyses, including an analysis of covariance, indicated that other variables, including the heaviness of body build and length of residences in Corpus Christi, were of much greater importance in predicting blood pressure. Implications of these findings for social epidemiology and health promotion are discussed.     

The epidemiology of St. Louis encephalitis in Corpus Christi, Texas, 1966.

In the summer of 1966, an epidemic of St. Louis encephalitis occurred in Corpus Christi, Texas, coincident with one occurring in Dallas about 563 km to the north. Among the 76 cases confirmed in Corpus Christi, there were two deaths; the attack rate was 41.0 per 100,000. In contrast with a concurrent outbreak in Dallas and the 1964 outbreak in Houston, attack rates were much higher in populations of the upper socioeconomic districts. This distribution may have resulted from the combined effects of an unusual concentration of vector mosquito breeding sites in storm sewers in the upper socioeconomic districts and a higher degree of residual immunity in the residents of the lower socioeconomic areas.     

Improving the evaluation of the efficiency of hygiene departments of State Sanitary and Epidemiologic Surveillance Centers

Methodological, technological, and organization characteristics of efficiency evaluation of specialists and hygienic departments engaged in a State Sanitary Surveillance (SSS) Center of the first level of management are presented. Main notions concerning the efficiency of SSS are formulated. A method for quantitative evaluation of the quality is offered, allowing comparison of compatible and equivalent parameters. Validation for mathematical models of efficiency and quality criteria is offered. Computer technology Sanepidotsenka (Sanitary epidemiological evaluation) is offered, which is used in the regulation of SSS Center activities aimed at maintenance of sanitary and epidemiological well-being of territories.     

Improving the documentation of vital signs: a business reengineering efficiency study

By upgrading its electronic medical record to include a Quick Vitals screen, the Henry Ford Health System increased the mean rate of entry of vital signs from 0.7% to 58.5%.     

Improving the outcome of acute stroke management

Recent research into stroke mechanisms suggests that it may be possible to reduce mortality and improve functional outcome in stroke patients, provided clinicians act quickly and appropriately. In this article, standards for optimal stroke management with new therapeutic strategies aiming to restore cerebral blood flow and to protect brain neurons will be discussed.     

Improving mental and neurological health research in Latin America: a qualitative study

Background  

Research evidence is essential to inform policies, interventions and programs, and yet research activities in mental and neurological (MN) health have been largely neglected, particularly in low- and middle-income countries. Many challenges have been identified in the production and utilization of research evidence in Latin American countries, and more work is needed to overcome this disadvantageous situation. This study aims to address the situation by identifying initiatives that could improve MN health research activities and implementation of their results in the Latin American region.     

Improving stroke outcome: the benefits of increasing availability of technology

INTRODUCTION: A decision analysis was performed to explore the potential benefits of interventions to improve the outcome of patients admitted to hospital with a stroke, in the context of the technology available in different parts of the world. METHODS: The outcome of death or dependency was used with a six-month end-point. RESULTS: Four settings were identified that would depend on the resources available. The proportion of stroke patients who were dead or dependent at six months was 61.5% with no intervention at all. Setting 4, with the only intervention being the delayed introduction of aspirin, produced a 0.5% absolute improvement in outcome (death or dependency), and the addition of an organized stroke unit (Setting 3) produced the largest incremental improvement, of 2.7%. Extra interventions associated with non-urgent computed tomography and thus the ability to avoid anticoagulation or aspirin for those with a haemorrhagic stroke (Setting 2), and immediate computed tomography scanning to allow the use of thrombolytics in non-haemorrhagic stroke (Setting 1), produced only small incremental benefits of 0.4% in each case. DISCUSSION: To reduce the burden of illness due to stroke, efforts at primary prevention are essential and likely to have a greater impact than even the best interventions after the event. In the absence of good primary prevention, whatever is possible must be done to reduce the sequelae of stroke. This analysis provides a rational basis for beginning the development of clinical guidelines applicable to the economic setting of the patient.     

Assessing exposure to disinfection by-products in women of reproductive age living in Corpus Christi, Texas, and Cobb county, Georgia: descriptive results and methods

We conducted a field study in Corpus Christi, Texas, and Cobb County, Georgia, to evaluate exposure measures for disinfection by-products, with special emphasis on trihalomethanes (THMs). Participants were mothers living in either geographic area who had given birth to healthy infants from June 1998 through May 1999. We assessed exposure by sampling blood and water and obtaining information about water use habits and tap water characteristics. Two 10-mL whole blood samples were collected from each participant before and immediately after her shower. Levels of individual THM species (chloroform, bromodichloromethane, dibromochloromethane, and bromoform) were measured in whole blood [parts per trillion (pptr)] and in water samples (parts per billion). In the Corpus Christi water samples, brominated compounds accounted for 71% of the total THM concentration by weight; in Cobb County, chloroform accounted for 88%. Significant differences in blood THM levels were observed between study locations. For example, the median baseline blood level of bromoform was 0.3 pptr and 3.5 pptr for participants in Cobb County and Corpus Christi, respectively (p = 0.0001). Differences were most striking in blood obtained after showering. For bromoform, the median blood levels were 0.5 pptr and 17 pptr for participants in Cobb County and Corpus Christi, respectively (p = 0.0001). These results suggest that blood levels of THM species vary substantially across populations, depending on both water quality characteristics and water use activities. Such variation has important implications for epidemiologic studies of the potential health effects of disinfection by-products.     

Improving the use of research evidence in guideline development: introduction

In 2005 the World Health Organisation (WHO) asked its Advisory Committee on Health Research (ACHR) for advice on ways in which WHO can improve the use of research evidence in the development of recommendations, including guidelines and policies. The ACHR established the Subcommittee on the Use of Research Evidence (SURE) to collect background documentation and consult widely among WHO staff, international experts and end users of WHO recommendations to inform its advice to WHO. We have prepared a series of reviews of methods that are used in the development of guidelines as part of this background documentation. We describe here the background and methods of these reviews, which are being published in Health Research Policy and Systems together with this introduction.     

某镇高血压、脑卒中的监测与干预

随着人民生活水平不断提高和现代生活方式的转变，居民的饮食结构已逐步发生变化，高脂肪、高胆固醇食品摄入量日益增加。运动量日趋减少，工作节奏加快，故心脑血管病的发病率明显上升。众所周知。高血压与脑卒中关系密切，脑卒中是严重危害人民身体健康和生命的主要慢性病之一。国内外的研究结果表明。脑卒中的发病是可以通过综合防治措施来预防的。上