Racial/ethnic health disparities in South Carolina and the role of rural locality and educational attainment.

BACKGROUND: The prevalence of selected health indicators were compared among the Catawba Indians, African Americans, and whites in South Carolina, considering the possible role of rural locality and education. METHODS: Catawba members were respondents of a 1998 survey (N = 808). Other South Carolina residents were respondents of the 1995-1997 Behavioral Risk Factor Survey (4,150 whites and 1,413 African Americans). Prevalence of cardiovascular disease, diabetes, hypertension, overweight, poor health, smoking, physical inactivity, and poor diet were compared among the racial/ethnic groups. Logistic regression analyses were conducted within strata of urban/rural locality and education to determine whether these factors were associated with the adverse health indicators. RESULTS: Both Catawba and African Americans had higher prevalence of diabetes, hypertension, overweight, poor health, physical inactivity, and poor diet than whites. In addition, prevalence of diabetes, poor health, smoking, and poor diet were higher among the Catawba than among African Americans. Restricting the analyses to comparisons within urban/rural locality had little effect, whereas restricting the analyses to comparisons by education level eliminated many of the disparities among those with low education. CONCLUSIONS: Prevalence of chronic disease and adverse health behavior are higher among the Catawba than among other residents of South Carolina, especially compared with white residents.

Behavioral and demographic correlates of diabetes, hypertension and overweight among the Catawba Indian Nation.

OBJECTIVE: In 1998, the Catawba Diabetes and Health Survey (CDHS) was conducted among adult members of the Catawba Indian Nation living in the Carolinas to determine the prevalence of diabetes and other health conditions, and to assess the population's health-related behaviors. DESIGN: A population-based sample of adult members of the Catawba Indian Nation (N = 633) were surveyed by telephone or in person regarding health status and health-related behaviors. Logistic regression was used to determine demographic and behavioral correlates of diabetes, hypertension, and overweight among the Catawba. RESULTS: Age-adjusted prevalence rates of self-reported diabetes, hypertension and overweight were 12.3%, 29.1%, and 63.8%, respectively. Older age was related to diabetes, hypertension, and overweight (P<.0001 each), and heavier weight status was related to diabetes (P = .026) and hypertension (P<.0001). Nearly 40% of the Catawba are physically inactive (29.5% men, 46.5% women). Physical inactivity was related to diabetes and hypertension among men only, and related to overweight among women only (P<.05 each). Current smoking was inversely related to overweight among men and women (P = .002). Dietary behavior was not associated with the health outcomes. CONCLUSION: Given the high rates of overweight and physical inactivity, reducing the rates of both may be very important for the health of the Catawba, considering their association with diabetes and hypertension.

Microdosimetry model for boron neutron capture therapy: I. Determination of microscopic quantities of heavy particles on a cellular scale.

Due to the limitations of existing microdosimetry models, a new model called MICOR has been developed to analyze the spatial distribution of microscopic energy deposition for boron neutron capture therapy (BNCT). As in most existing models, the reactions independent of the incident neutron energy such as the boron and the nitrogen capture reactions can be considered. While other models do not include reactions that are dependent on the neutron energy such as the proton recoil reaction, the present model is designed so that the energy deposition resulting from these reactions is included. The model MICOR has been extended to enable the determination of the biological effects of BNCT, which cannot be done with the existing models. The present paper describes the determination of several microscopic quantities such as the number of hits, the energy deposition in the cell nucleus, and the distribution of lineal and specific energy deposition. The companion paper (Radiat. Res. 155, 000-000 2001) deals with the conversion of these microscopic quantities into biological effects. The model is used to analyze the results of a radiobiological experiment performed at the HB11 facility in the HFR in Petten. This analysis shows the value of the model in determining the dose depositions on a cellular scale and the importance of the extension to the energy deposition of the proton recoil.

Microdosimetry model for boron neutron capture therapy: II. Theoretical estimation of the effectiveness function and surviving fractions.

A model has been developed to obtain a better understanding of the effects of boron neutron capture therapy (BNCT) on a cellular scale. This model, the microdosimetry model MICOR, has been developed to include all reactions important for BNCT. To make the model more powerful in the translation from energy deposition to biological effect, it has been designed to be capable of calculating the effectiveness function. Based on this function, the model can calculate surviving fractions, RBE values and boron concentration distributions. MICOR has been used to analyze an extensive set of biological experiments performed at the HB11 beam in Petten. For V79 Chinese hamster cells, the effectiveness function is determined and used to generate surviving fractions. These fractions are compared with measured surviving fractions, which results in a good agreement between the measured and calculated surviving fractions (within the uncertainties of the measurements).

Physical activity and public health: training courses for researchers and practitioners.

The authors explore development of courses in continuing education intended to provide additional research and practice capacity for addressing the growing burden of chronic disease and disability from physical inactivity. Two annual training courses on physical activity and public health are described. The courses are developed with funding from the Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, Division of Nutrition and Physical Activity. The University of South Carolina, School of Public Health, Prevention Research Center has been an active collaborator and was responsible for developing and implementing the courses. An eight-day "Course on Research Directions and Strategies," is offered to postdoctoral researchers, and practitioners may take a six-day "Practitioners' Course on Community Interventions." Both courses are designed to increase the number of professionals qualified to implement physical activity community interventions and conduct physical activity and public health research.

Boron neutron capture therapy (BNCT): implications of neutron beam and boron compound characteristics.

The potential efficacy of boron neutron capture therapy (BNCT) for malignant glioma is a significant function of epithermal-neutron beam biophysical characteristics as well as boron compound biodistribution characteristics. Monte Carlo analyses were performed to evaluate the relative significance of these factors on theoretical tumor control using a standard model. The existing, well-characterized epithermal-neutron sources at the Brookhaven Medical Research Reactor (BMRR), the Petten High Flux Reactor (HFR), and the Finnish Research Reactor (FiR-1) were compared. Results for a realistic accelerator design by the E. O. Lawrence Berkeley National Laboratory (LBL) are also compared. Also the characteristics of the compound p-Boronophenylaline Fructose (BPA-F) and a hypothetical next-generation compound were used in a comparison of the BMRR and a hypothetical improved reactor. All components of dose induced by an external epithermal-neutron beam fall off quite rapidly with depth in tissue. Delivery of dose to greater depths is limited by the healthy-tissue tolerance and a reduction in the hydrogen-recoil and incident gamma dose allow for longer irradiation and greater dose at a depth. Dose at depth can also be increased with a beam that has higher neutron energy (without too high a recoil dose) and a more forward peaked angular distribution. Of the existing facilities, the FiR-1 beam has the better quality (lower hydrogen-recoil and incident gamma dose) and a penetrating neutron spectrum and was found to deliver a higher value of Tumor Control Probability (TCP) than other existing beams at shallow depth. The greater forwardness and penetration of the HFR the FiR-1 at greater depths. The hypothetical reactor and accelerator beams outperform at both shallow and greater depths. In all cases, the hypothetical compound provides a significant improvement in efficacy but it is shown that the full benefit of improved compound is not realized until the neutron beam is fully optimized.

The modifiable factors contributing to leading causes of death in South Carolina.

In 1996, there were 34,035 deaths in South Carolina. Almost 70 percent of these deaths were due to chronic diseases. There are known ways to prevent chronic diseases from developing or at least delay their developmental process, thereby lengthening years of life. The purpose of this paper is to report modifiable risk factors for mortality related to leading causes of death. The top ten causes of death in South Carolina were obtained from the South Carolina Department of Health and Environmental Control. Estimates of the number of deaths due to certain modifiable risk factors were made using results of a study published by McGinnis and Foege. The percentage of deaths due to each cause was adapted to South Carolina death certificate data from the national estimates. Results indicate that small modifications in individual lifestyles could prevent or delay nearly 50 percent of deaths in South Carolina annually. Tobacco use, diet and physical activity, and misuse of alcohol contribute to the largest number of deaths. Other modifiable behaviors contributing to the 50 percent mortality are microbial agents, toxic agents, firearms, sexual behavior, motor vehicle accidents, and illicit use of drugs. The implication in these findings is that these risk factors for mortality are mainly modifiable. There are many causes of death that may be delayed due to these modifiable risk factors. By looking at preventable causes of death, rather than focusing on traditional causes of death, it becomes clear that prevention strategies are critically important.

Overview of the Diabetes Initiative of South Carolina.

Implementation is underway for many of these programs, and there are descriptions of activities elsewhere in this symposium. The Board recognizes that in dealing with the complications of a chronic disease like diabetes, many years of intense effort will be needed before significant results may be appreciated. Progress will be monitored regularly by the Surveillance Council and SCDCP/DHEC, and modifications of the plan will be made by the Board at intervals after review of the data. We are optimistic that over the next decade, this system will make a significant impact to reduce mortality, morbidity, and costs of diabetes, and the result will be an increased quality of life for people affected by diabetes in South Carolina.

The compound factor of the 10B(n,alpha)7Li reaction from borocaptate sodium and the relative biological effectiveness of recoil protons for induction of brain damage in boron neutron capture therapy.

To make clinical trials of boron neutron capture therapy safe for patients, it is necessary to know the relative biological effectiveness (RBE) of the radiation components and the compound factor of the boron carrier to be used. Here a method is derived to determine the RBE of recoil protons and the compound factor of compounds from in vivo experiments with different concentrations of boron. The method uses a simultaneous fit of both these parameters to all experimental data. This method is applied to the studies of tolerance of healthy tissue in dogs at the High Flux Reactor in Petten, The Netherlands. The RBE for the recoil protons generated by the neutrons present in the epithermal neutron beam [together with the RBE of the protons from the 14N(n,p)14C reaction] for induction of severe neurological symptoms was found to be 3.93+/-0.43 (95% confidence limits 3.06-4.79), and 2.33+/-0.14 (2.04-2.61) for induction of changes detectable by magnetic resonance imaging. The compound factor for Na2B12H11SH in brain tissue, using severe neurological symptoms as end point, was determined to be 0.37+/-0.06 (95% confidence limits 0.24-0.50). For changes detectable by magnetic resonance imaging, the value was found to be 0.65+/-0.04 (0.58-0.73).

Computational dosimetry and treatment planning for boron neutron capture therapy.

The technology for computational dosimetry and treatment planning for Boron Neutron Capture Therapy (BNCT) has advanced significantly over the past few years. Because of the more complex nature of the problem, the computational methods that work well for treatment planning in photon radiotherapy are not applicable to BNCT. The necessary methods have, however, been developed and have been successfully employed both for research applications as well as human trials, although further improvements in speed are needed for routine clinical applications. Computational geometry for BNCT applications can be constructed directly from tomographic medical imagery and computed radiation dose distributions can be readily displayed in formats that are familiar to the radiotherapy community.

Self-reported prevalence of diabetes and preventive health care practices among people with diabetes in South Carolina.

In conclusion, South Carolina has a higher prevalence of diabetes compared to the national average. Age is a major factor associated with increased prevalence. African Americans had a disproportionately higher prevalence of diabetes relative to white Americans in South Carolina. Compared to the standards of diabetes care recommended by the ADA, health care practice by people with diabetes and health professionals still needs to be improved. Diabetes communication programs, including diabetes education for people with diabetes and health professional education, continue to be necessary for the improvement of diabetes care.

Body fat distribution and race differences in apolipoprotein A1.

OBJECTIVE: This is the first study to assess the role of waist-to-hip ratio in explaining race differences in levels of serum apolipoprotein A1, a protective risk factor for atherosclerosis. METHODS: Linear regression analyses were used in a community-based survey of 3,043 adults (23.5% African-American) to assess associations of race, age, anthropometric measures, education, diabetes, blood pressure medication use, cigarette smoking, and leisure-time physical activity with apolipoprotein A1 levels. RESULTS: Higher apolipoprotein A1 levels were observed among African-American than among white adults (African-American men: +15.6 mg/dl than white men, African-American women: +3.1 mg/dl more than white women; p < 0.05). Waist-to-hip ratio and other variables did not account for race differences among men. African-American women had +8.6 mg/dl higher levels than white women after adjustment for differing distributions of waist-to-hip ratio, age, body mass index and education. Cigarette smoking, physical activity, and medical history accounted for no further differences among women. CONCLUSIONS: Higher levels of obesity indicators and lower educational attainment among African-American women reduced a potentially greater beneficial race difference in apolipoprotein A1. These findings also suggest that other environmental and biochemical factors may play roles in explaining the higher protective levels of apolipoprotein A1 observed among African-American children and adults.

An improved neutron collimator for brain tumor irradiations in clinical boron neutron capture therapy.

To improve beam penetration into a head allowing the treatment of deeper seated tumors, two neutron collimators were built sequentially and tested for use in the clinical boron neutron capture therapy (BNCT) program at the epithermal neutron irradiation facility of the Brookhaven Medical Research Reactor. The collimators were constructed from lithium-impregnated polyethylene, which comprises Li2CO3 powder (approximately 93% enriched isotopic 6Li) uniformly dispersed in polyethylene to a total 6Li content of 7.0 wt. %. The first collimator is 7.6 cm thick with a conical cavity 16 cm in diameter on the reactor core side tapering to 8 cm facing the patient's head. The second collimator is 15.2 cm thick with a conical cavity 20 cm in diameter tapering to 12 cm. A clinical trial of BNCT for patients with malignant brain tumors is underway using the first collimator. Results of phantom dosimetry and Monte Carlo computations indicate that the new 15.2 cm thick collimator will improve the neutron beam penetration. Thus, the second collimator was made and will be used in an upcoming clinical trial. In-air and in-phantom mixed-field dosimetric measurements were compared to Monte Carlo computations for both collimators. The deeper penetration is achieved but at a sacrifice in beam intensity. In this report, a performance comparison of both collimators regarding various fluence rate and absorbed dose distributions in a head model is presented and discussed.

Education, health behaviors, and the black-white difference in waist-to-hip ratio.

Few epidemiologic studies have investigated the impact of body mass index, low educational attainment, cigarette smoking, and physical activity on the considerable black-white difference in waist-to-hip ratio. These relationships were assessed with multivariable linear regression among 3,094 adults (24% black) who were examined in 1987 in South Carolina. The unadjusted mean waist-to-hip ratio was lower for black men than for white men (-0.03 units) and higher for black women than for white women (+0.03 units). After adjustment for age, body mass index, education, smoking, and physical activity, the black-white difference in mean waist-to-hip ratio was -0.02 units (p < 0.001) among men and +0.01 units (p < 0.01) among women. Although differing distributions of age, body mass index, and educational attainment accounted for a 59% reduction in the black-white difference among women, these factors did not explain the difference among men. Thus, these results suggest that other environmental or biologic factors may also play an important role in the marked variation in body fat distribution between the two ethnic groups. The results also support the importance of the prevention of cigarette smoking and overweight in potentially preventing abdominal obesity in both black adults and white adults.

Trends in mortality and health behaviors: status of white and African-American women.

A substantial proportion of mortality in the United States can be attributed to three major behaviors: using tobacco, maintaining an unhealthy diet, and being physically inactive. Using data from the South Carolina mortality files and Behavioral Risk Factor Surveillance System we were able to document state trends in mortality, cigarette smoking, physical inactivity, and unhealthy dietary practices. We found that, in spite of the declines in heart disease and stroke mortality noted nationally and in the state, the risk factor profiles for most women in South Carolina did not improve. This analysis further suggests that physical inactivity and dietary issues (excess caloric intake, low fruit and vegetable consumption) would be good choices for lifestyle interventions among women in South Carolina, not only because they ultimately affect mortality, but also because they exert interim effects on morbidity, including physical functioning and independence.

Evaluation of the Heart To Heart Project: lessons from a community-based chronic disease prevention project.

PURPOSE: To present an evaluation of a 5-year, community-based, chronic disease prevention project managed by a state health department to determine whether the department could replicate similar previous projects that had received more funding and other resources. DESIGN: The evaluation used a matched comparison design and a review of archive and interview data. SETTING: Florence, South Carolina (population: 56,240). SUBJECTS: A random sample of 1642 persons in Florence (and 1551 in the comparison) who responded to a risk factor questionnaire and underwent a physical assessment; 70.7% of baseline subjects participated in the postintervention. Forty key persons were interviewed concerning project effectiveness. INTERVENTIONS BY PROJECT: Walk-a-thons, a speakers' bureau, media messages, restaurant food labeling, and cooking seminars. More than 31,000 participants were involved in 585 activities. MEASURES: Questionnaires focused on hypertension, obesity, high cholesterol, smoking, and exercise. Physical assessments determined lipid, lipoprotein, apolipoprotein, and blood pressure levels. Analysis of covariance was used for baseline and postintervention comparisons. Content analysis was used on archive and interview data. RESULTS: The project had a slightly favorable intervention effect on cholesterol and smoking, but failed to have an effect on other risk factors for cardiovascular disease. The project influenced community awareness, enlisted influential community members, and fostered linkages among local health services. CONCLUSIONS: Health departments can be instrumental in community risk reduction programming; however, they may not replicate projects having greater resources.