Throughout its history, the NHLBI has been a leader in conducting and supporting research and programs to eliminate health disparities that exist between various segments of the U.S. population. The Institute has not only initiated research projects with significant racial and ethnic minority participation to compare health status between various populations, but also given high priority to programs that focus exclusively on minority health issues.
Since FY 1991, the Institute has had procedures in place to ensure full compliance with the NIH Policy on Inclusion of Women and Minorities as Subjects in Clinical Research. As a result, all NHLBI-supported research that involves human subjects includes minorities, with the exception of a very few projects for which a compelling justification for limited diversity in the study population exists. Thus, all segments of the population can benefit from the Institute's research programs.
It has long been a goal of the NHLBI to increase the number of individuals from underrepresented groups in biomedical and behavioral research. Selected FY 2012 activities addressing this goal include the following:
The Office of Research Training and Minority Health (ORTMH) within the Office of the Director provides oversight for, and coordinates, supports, and evaluates Institute programs related to minority health outcomes, including research, research training and career development, public outreach, and translation of research findings. The ORTMH also coordinates activities to foster greater participation of underrepresented minorities, individuals from disadvantaged backgrounds, and individuals with disabilities in NHLBI research and research training and career development programs. Selected FY 2012 activities include the following:
See Chapter 13 for additional NHLBI-supported research training and career development programs for individuals from diverse backgrounds.
The following text describes selected current projects that focus on minority populations and reflect the Institute's research portfolio related to minority health. Additional information can be found in Chapters 9, 10, and 11.
Long-term epidemiologic studies are critical to uncovering risk factors that lead to disease. The Institute has initiated several major studies of heart disease focused significantly or completely on minority populations:
The Institute supports components of the NHANES that track the prevalence of disease and risk factors for cardiovascular and lung diseases by race and ethnicity in the U.S. population and the National Longitudinal Mortality Study that analyzes socioeconomic, demographic, occupational, and racial differentials in mortality in the United States.
The NHLBI also supports a variety of investigator-initiated research activities across a range of racial and ethnic groups on health disparities in heart, lung, and blood diseases and sleep disorders and on risk factors and genetic contributors to their development. Many of them are ancillary studies to NHLBI-initiated cohort studies.
Investigator-initiated studies on cardiovascular risk factors in underrepresented racial and ethnic groups range in focus from biological to environmental, psychosocial, and cultural factors. One study among blacks in the JHS is characterizing the relationships between vascular function and CVD risk factors and indicators of subclinical CVD, and detecting gene variants that influence vascular function. A second study is investigating the effects of low vitamin D levels and CVD risk in blacks in the biethnic ARIC cohort. A third study is using echocardiographic examinations of a subsample of adult participants in the HCHS to determine a population-based estimate of the prevalence of abnormal systolic and diastolic cardiac function in Hispanic adults and the degree of heterogeneity in cardiac function between Hispanic subgroups and to establish the relationship of determinants particularly relevant to the Hispanic population (diabetes biomarkers and psychosocial/socioeconomic factors) to cardiac structure and function.
Other studies are determining geographic and ethnic variations in the prevalence of CHD risk factors, assessing the role of the neighborhood environment on the development of CVD and its risk factors in MESA participants, and investigating risk factors linked to atherosclerosis and disease progression in individuals of South Asian descent who are living in America.
Genetic epidemiology is concerned with the role of genetic factors in the etiology of disease within groups of relatives and the interplay of genetic factors with environmental factors. NHLBI-supported studies include those focusing on gene discovery through both linkage studies in family-based samples and GWASs in population-based samples; the effects of gene–environment interactions on risk factors and health; and genotypic characterization in relationship to intermediate phenotypes, such as biomarkers. An Institute-initiated study is investigating functional aspects of genetic variation in humans.
Genetic epidemiologic research is also beginning a transition to predicting and assessing genetic risk and reporting genetic results to participants of research studies. Examples are studies of genetics of hypertension in populations of West African origin; the role of stress in gene–environment interaction in a multi-ethnic population; the contribution of genetic variation to obstructive sleep apnea, impaired endothelial function, and central blood pressure in Mexican Americans; genetic variation that underlies obesity and obesity-related phenotypes among Samoan adults; and rare variants for hypertension in Taiwan Chinese.
The NHLBI is committed to supporting research that will contribute to reducing health disparities among racial and ethnic minorities. Relevant Institute-initiated programs include:
Compared with white men, black men are disproportionately affected by premature mortality and CVD, perhaps in part due to their greater exposure to social and economic adversity across the lifespan. One study is seeking to understand the developmental antecedents of poor sleep and cardiovascular risk in black and white men who have been followed since they were enrolled in the first grade. Data obtained include health behaviors and academic and social competence; parental health behaviors; parenting practices; household SES; and neighborhood characteristics, including census tract SES, exposure to violence, and community cohesiveness and involvement. Research results will facilitate the design of interventions to prevent adverse health consequences of early life experiences, thereby reducing health disparities.
The NHLBI hosts Children and Clinical Studies (see http://www.ChildrenAndClinicalStudies.nhlbi.nih.gov), an educational Web site for children and their families and health care providers to improve their understanding of pediatric research. The site offers information in English and Spanish about the importance of research on children, safety measures in clinical trials, and potential effects on a family when a child is enrolled in a study. The site also has a section about minority interests and concerns.
The NHLBI, through the DARD, translates research findings into practice by facilitating the development of clinical practice guidelines; communicating research advances; and disseminating health information to physicians, health care professionals, patients, and the public on ways to prevent or treat diseases within the Institute's mandate.
In 2011, the Institute initiated the National Program to Reduce Cardiovascular Risk (NPRCR) aimed at reducing the risk of CVD by focusing on implementing evidence-based clinical practice guidelines and interventions to reduce cardiovascular risk factors throughout the lifespan. Topics include cholesterol, blood pressure, and obesity, among others. NPRCR also includes efforts to reduce health disparities in CVD risk.
The Institute supports the following activities to improve cardiovascular health in racial and cultural/ethnic groups:
In addition to the activities mentioned above, the Institute has prepared and distributed publications on CVD prevention for racial and ethnic minority populations. They include the following:
The educational materials listed throughout this chapter can be obtained from the NHLBI public Web site or through the NHLBI online catalog.
Heart failure (heart muscle dysfunction) affects approximately 5 million Americans and is a growing public health concern. It is frequently the end result of other conditions, such as hypertension, diabetes, and prior heart attacks.
Findings from the CARDIA study showed that heart failure before age 50 is substantially more common in blacks than in whites. Among black participants, risk factors such as high blood pressure, obesity, and chronic kidney disease often preceded heart failure by 10 to 20 years.
The Institute supports a clinical trials network to facilitate the translation of basic science discoveries into clinical applications and a drug trial in patients with heart failure and preserved ejection fraction equal to or greater than 45 percent:
An investigator-initiated study is assessing the effect of a phosphodiesterase type 5 inhibitor in patients with heart failure due to systolic dysfunction. In this study, concerted efforts are being made to recruit black patients who do not tolerate hydralazine and nitrates, which are guideline-based therapies for this population and which are contraindicated with phosphodiesterase type 5 inhibitors.
High blood pressure is a serious health problem that is especially prevalent and severe among minorities.
The NHLBI supports a number of investigator-initiated studies to identify genes linked to hypertension in blacks, Mexican Americans, persons of Asian ethnic background, and whites to determine whether part of the disparity in prevalence can be attributed to genetic differences among the groups. Genes under investigation include those associated with the renin-angiotensin system, the autonomic nervous system, and sodium transport.
The role of dietary factors, particularly macronutrients, in the etiology of high blood pressure is another area of investigation. Scientists are conducting epidemiologic studies among participants with diverse ethnicity, SES, and dietary habits in four countries to determine the effect of selected dietary components (proteins, lipids, carbohydrates, amino acids, calcium, magnesium, sodium, potassium, antioxidants, fiber, and caffeine) on blood pressure.
Researchers are also seeking to understand the role of obesity in the development of high blood pressure. One study is investigating the effect of natriuretic peptides (hormones produced by the heart) in blood pressure regulation and dietary salt sensitivity, and relating findings to previous findings that obese individuals have decreased numbers of circulating natriuretic peptides. Approximately 40 percent of study participants are expected to be from minority subgroups. Another study is determining the contributions of the sympathetic and nitric oxide systems to obesity-associated hypertension in black women.
Treatment and Prevention
Identifying effective treatment strategies for various populations requires large-scale studies with representative populations in sufficient numbers.
The Institute also supports a number of investigator-initiated studies to prevent hypertension and improve blood pressure control in racial and ethnic minorities. Interventions target both lay and medical communities. Strategies being tested include communication skill enhancement, organizational change, educational programs, lifestyle and nutritional counseling, use of technology, case management, pharmacy-based interventions, and provision of care by community health workers and other nontraditional providers.
One study is testing a church-based lifestyle intervention to reduce blood pressure using group classes and motivational interviews to help participants make and maintain therapeutic lifestyle changes. Approximately 400 blacks with high blood pressure are expected to participate. Another study is determining whether overcoming “clinical inertia” by providing clinicians with patients' electronic adherence to medication records will lead to more intensive treatment and improved blood pressure control in patients with uncontrolled blood pressure. The majority of the patients are black. A third study is determining whether vitamin D and fish oil supplements can lower blood pressure and prevent hypertension in a multiracial and ethnic population.
Hypertension in adolescents is no longer a rare occurrence but is rising as a result of the obesity epidemic in the United States. An Institute-initiated study within the Childhood Obesity Prevention and Treatment Research Consortium is focusing on interventions to treat obesity and reduce blood pressure in urban youth:
An investigator-initiated study is comparing the effects of a behavioral intervention based on the DASH diet to routine nutrition care on changing diet quality, blood pressure, hypertension status, and vascular function in adolescents with elevated blood pressure. Thirty-five percent of participants are from various racial and ethnic populations.
The NHLBI has developed a number of outreach activities to inform minority populations of the importance of blood pressure control. Several publications and Web-based products have been developed and distributed for health professionals, patients, and the public. Some examples are:
The Institute supports investigator-initiated studies to identify genes that influence lipoprotein profiles in various racial and ethnic groups. Research findings could offer an explanation for differences in susceptibility to CHD found among the groups. A project involving extended families of Mexican Americans in the San Antonio Family Heart Study has detected and mapped many quantitative trait loci (QTLs) for CVD risk factors, including some that influence HDL and LDL levels. Scientists are seeking to identify genes for QTLs that are related to lipoproteins.
Research has shown that patients with elevated LDL levels who have been advised to make lifestyle changes and to take statins often do not comply with the prescribed regimens. An investigator-initiated study is seeking to develop and evaluate an interactive virtual environment system to increase the initiation and maintenance of medication adherence and therapeutic lifestyle change in patients who are at risk for CHD. Patients will be able to access the system to seek advice from a virtual health care provider and get assistance in developing an effective care plan that is based on clinical guidelines.
The Institute has prepared the following publications on blood cholesterol for minority audiences:
Obesity is a major health concern that affects children and adults. Minorities—including American Indians, blacks, and Mexican Americans—are especially at risk. Data from the 2007–2008 NHANES show that 34 percent of adults and 17 percent of children aged 2–19 years are obese. Understanding the causes of obesity could lead to effective strategies to combat it. A long-term investigator-initiated study is examining parental and extended family influences on the development of childhood obesity in Mexican American children. Another study is elucidating the interconnected biological and social pathways associated with adolescent obesity and risk for later development of type 2 diabetes and CVD in Latin American youth. The goal of the study is to identify modifiable conditions to prevent obesity and related diseases.
The NHLBI funds several studies that focus on genetic risk factors for obesity in one or more minority populations. Evidence for obesity genes has been identified on chromosome 4 in American Indians, on chromosome 9 in Mexican Americans, and on chromosomes 5 and 6 in blacks. In some cases, the results confirm those found in European Americans, and in other cases, the results represent novel findings.
Researchers have found that black and Hispanic children are especially likely to develop sleep apnea. An investigator-initiated study will assess the role of obesity in the development of abnormalities that increase the likelihood of developing sleep apnea and whether the problem can be corrected with weight loss. Eighty percent of participants are black. Another study with multi-ethnic participation is determining whether obese children with sleep apnea are at increased risk of cognitive impairment and vascular disease.
Treatment and Prevention
The NHLBI has initiated programs to test approaches for treating or preventing obesity:
The Institute supports a number of studies on the effectiveness of obesity prevention and control interventions among diverse populations. Studies that focus on obese children and adolescents are evaluating the effect of adding environmental approaches to a standard family-based intervention to reduce overeating in obese children primarily from a minority population; exploring whether naturally occurring social support networks can help parents manage their children's weight in a population where 40 percent of the children are expected to be from racial and ethnic minority populations; testing a community-based, multimodal, early childhood intervention to reduce obesity in American Indians; developing a culturally appropriate intervention for teen mothers, many of whom are from racial and ethnic and low socioeconomic backgrounds, to prevent obesity in their children; evaluating an intensive school-based intervention that involves physical activity and diet to reduce the prevalence of obesity among a diverse racial and ethnic population of high school students; and testing an intervention, delivered by a handheld computer, for improving diet and exercise in obese adolescents, half of whom are black.
Studies of obese adults are determining whether supplementing nurse and dietitian case management care with structured environmental support, provided by community health workers, improves weight loss and maintenance relative to usual care in a mostly obese Hispanic population of low SES; determining the effectiveness of various financial incentives to get obese individuals from mostly diverse minority populations to sustain weight loss; assessing the efficacy of Web-based pregnancy and postpartum behavioral intervention to prevent weight retention after childbirth in black women compared with usual care; and evaluating an intervention that supports primary care treatment of obesity in adults with at least one other cardiovascular risk factor. One project has strong participation from Hispanics.
Many obese adults have difficulty breathing upon physical exertion and therefore are unable to exercise sufficiently. It is unclear whether this is because the individuals are in poor physical condition and could be helped with endurance exercise training, or whether obesity-related respiratory changes have occurred that necessitate weight loss before exercise training can be effective. Researchers are planning to investigate this question in obese individuals by assessing the effect of endurance exercise training (without weight loss) versus weight loss (without exercise training) on breathing difficulties after physical exertion. Approximately 40 percent of participants will be from minority populations.
The NHLBI has prepared and distributed health information for minorities on losing excess weight:
Despite substantial research about the benefits of physical activity on CVD and its risk factors, physical inactivity is highly prevalent, especially among minority populations. Researchers have observed an age-related decline in physical activity or aerobic capacity in the biracial cohorts of two Institute-initiated longitudinal cohort studies.
The transition from elementary school to middle school marks a critical stage in the development of young people and the period during which physical activity tends to decline dramatically. An investigator-initiated study is investigating factors that contribute to the decline and the potential moderating effects of gender, race, socioeconomic status, and neighborhood environment on factors that influence changes in physical activity. The majority of participants will be from racial and ethnic minority populations.
A comprehensive intervention involving in-school counseling sessions, interactive Internet-based sessions, and an after-school physical activity program is seeking to motivate middle school-aged girls from mostly Hispanic and black populations to achieve regular moderate-to-vigorous physical activity. Another study will collect data on aspects of neighborhood environments that are most often associated with physical activity in adolescents and determine whether this information can be used, via interventions offered in the offices of pediatricians, to help children increase their physical activity. A third study will develop and evaluate policies to increase physical activity and improve nutrition during summer and after-school programs sponsored by the YMCA. Approximately 50 percent of the children are expected to be black.
Regular physical activity is important for cardiovascular health throughout life. Investigators are designing and evaluating a long-term, multilevel physical activity intervention for sedentary residents who are living in retirement communities. The intervention uses a variety of elements, including self-monitoring with a pedometer, group sessions and peer mentoring, and such environmental components as tailored walking maps. Approximately 25 percent of participants are expected to be from racial and ethnic minority populations.
Several investigator-initiated studies are evaluating culturally appropriate interventions to increase physical activity. Projects include those that use faith-based approaches involving church leaders and congregations to increase activity levels in blacks and those that test culturally targeted interventions in schools or among pregnant women and parents with young children.
Several projects are using mobile phone technology to increase physical activity and decrease sedentary behaviors. These studies capitalize on recent advances in communication technologies, such as “smart phones,” that offer a new way to deliver convenient and sustainable adherence strategies. In one study, women are receiving prompts, video clips, and individualized feedback via their cell phones to help them increase their physical activity levels. Approximately 60 percent of the women are expected to be from racial and ethnic minority populations. In another study with large minority participation, researchers are assessing a program that is designed to improve diet and activity levels in sedentary people with poor quality diets; all participants use “smart phones” to monitor themselves and transmit information to a personal coach.
The Institute has prepared and distributed the following publications for minorities on the importance of physical activity and ways to become more physically active:
The Institute also has developed a Web-based application on physical activity for lay health educators in English and Spanish, which can be found at http://hin.nhlbi.nih.gov/salud/pa/index.htm.
Smoking is a major risk factor for CHD, stroke, COPD, and other cardiovascular and respiratory conditions and is the leading cause of preventable death. Although considerable progress has been made in reducing smoking rates and providing effective prevention and cessation interventions, additional research is needed to extend these efforts and improve the maintenance of behavior change.
The Institute has initiated smoking intervention programs in specialized groups:
The NHLBI supports a number of studies of smoking cessation in underserved populations. One study among predominately black women who live in public housing neighborhoods is evaluating smoking cessation interventions that use a combination of strategies—including contact with community health workers, small-group behavioral counseling, and neighborhood support groups. Another study is comparing the efficacy of a hospital-initiated behavioral intervention to conventional care practices in reducing household secondhand smoke exposure in low-income, multi-ethnic parents of infants who were in neonatal intensive units. Two studies among military personnel are testing interventions that focus on smoking cessation and subsequent abstinence. Approximately 35–40 percent of participants are expected to be from racial and ethnic minority populations.
The Institute has prepared the following publications on smoking cessation for minorities:
A large and consistent body of evidence has demonstrated that psychosocial factors—such as depression, stress, and low social support—are associated with elevated risk for CVD and major adverse cardiac events in heart disease patients. Additionally, race and ethnicity, gender, and social class are important factors that can influence these associations in important ways.
The NHLBI is funding research to identify more precisely the nature of the relationship between depression and adverse cardiac outcomes. One study is testing the hypothesis that physical inactivity mediates the relationship between depression and cardiac outcome risk. Sixty percent of participants are expected to be from racial and ethnic populations. Another study is seeking to increase understanding of the mechanisms that lead to death in depressed patients with heart disease by assessing the effects of stress on heart and brain function in heart disease patients with and without depression. Approximately 45 percent of participants are expected to be from minority groups. A third study is examining the potential epigenetic mechanisms that link depression and CVD. More than 50 percent of participants are expected to be black. A fourth study is identifying depression phenotypes and mechanisms that cause patients who have experienced an acute coronary event to have excess cardiac and mortality risk. Participants are from various racial and ethnic populations.
The Institute supports research on the interactions of psychosocial factors with race and ethnicity, environmental factors, and low SES in the development of CHD. One study is examining the contribution of social stressors and physical environments at the individual and neighborhood levels in the development of metabolic and cardiovascular risk profiles in adolescents with low SES. Most participants are from various racial and ethnic minority populations. Another study is investigating the contribution of biobehavioral factors (hostility, anxiety, and heightened cardiovascular reactivity to stress) in the etiology, pathogenesis, and course of CHD. Racial differences in stress-induced physiologic responses are also being examined. A third study is determining whether “everyday discrimination” (e.g. , subtle, day-to-day forms of unfair treatment, such as minor insults experienced by black women as a function of their marginalized status) is an important risk factor in the development of CVD in black women.
The nature of the relationship between acute and chronic forms of stress and cardiac morbidity and mortality is particularly relevant to minority populations, because stress induced by environmental, social, and discriminatory influences can be significant. A study is investigating whether the effect of acute and chronic exposure to established risk factors (depressive symptoms, major life events, and lack of social support) for CVD during a 5-year period is related to a 2-year increase of subclinical CVD in a sample of women undergoing menopause. Fifty-five percent of participants will be black.
The Institute supports several investigator-initiated studies to develop and evaluate interventions to improve cardiovascular outcomes. One study is seeking to determine the efficacy of a mindfulness-based personalized health plan intervention on reducing inflammation, a significant predictor of future CVD, via reductions in traditional risk factors, selected psychosocial attributes, and stress-reactivity among at-risk adults. Approximately 30 percent of participants will be from minority populations. Another study is evaluating the effectiveness of stress management training combined with exercise-based cardiac rehabilitation as a way to reduce stress in vulnerable cardiac patients. Approximately 25 percent of participants are black. A third study is developing and evaluating an intervention among racial minorities that reduces the impact of bias by reducing stereotypic perceptions that render patients and providers less able to communicate effectively and impair the effect of the visit to improve patient self-management behavior. Additional studies are investigating whether stress management in a high-risk population of blacks with hypertension can influence cardiovascular risk factors.
Obesity dramatically increases the risk of many diseases, such as CVD and type 2 diabetes. An investigator-initiated study is seeking to identify obesity-induced epigenetic changes in the immune and inflammatory response and evaluate whether these changes are associated with the risk of CVD and type 2 diabetes. Fifty percent of participants will be black.
Diabetes mellitus is a strong risk factor for CVD. Individuals with type 2 diabetes are 2 to 4 times more likely to be at risk for CHD than the general population. Using GWASs, investigators have identified several genetic variants for CHD in the general population. An investigator-initiated study is seeking to identify new genetic variants for excessive risk of CHD in diabetic patients, assess the genetic effects on intermediate biochemical changes, and examine gene–environment interactions. One of the data sources will come from the Costa Rican Diabetes–CHD case-control study.
Treatment and Prevention
The NHLBI supports clinical trials to determine the benefits of various strategies to reduce CVD among patients with diabetes or treat patients with coronary artery disease and diabetes:
An investigator-initiated study is comparing the effectiveness of two strategies of coronary revascularization—coronary percutaneous stenting versus coronary artery bypass surgery—in patients with diabetes and multivessel coronary artery disease. Twenty-seven percent of participants are from minority populations.
Gestational diabetes during pregnancy is a risk factor for CVD. Research is underway that will design and test a behavioral intervention to improve postpartum CVD-preventive health behaviors and promote primary followup care in women with gestational diabetes, most of whom are black.
The Institute has prepared the following publications on diabetes for minorities:
Use of multidrug antiretroviral therapy has improved life expectancy of HIV-infected individuals to the point that HIV/AIDS is now a chronic condition for many patients. As a result, CVD is presently causing an increasing proportion of the deaths of HIV-infected individuals.
The Institute initiated research on the development of CVD in HIV-infected patients and potential management strategies:
The NHLBI supports research on several lung diseases—such as asthma, sarcoidosis, TB, and HIV-related lung diseases—that disproportionately affect minorities. The following section provides examples of research to address health disparities in lung diseases; selected sleep disorders are also included.
Asthma is a chronic lung disease that inflames and narrows the airways. It affects people of all ages and most often starts in childhood. In the United States, more than 24 million people are known to have asthma, and more than 7 million of them are children. Asthma disproportionately affects racial and ethnic minorities, such as blacks and Puerto Ricans. These groups have higher rates of emergency department visits, hospitalizations, and deaths due to asthma than their white counterparts.
The NHLBI has initiated additional studies to improve understanding of the etiology and pathophysiology of asthma:
The Institute also supports investigator-initiated projects on the etiology and pathophysiology of asthma. Several projects focus on the role of genetics in the development of asthma. One study will identify genetic, biologic, and immunologic characteristics and environmental exposures that interact in children who experience severe bronchiolitis caused by the respiratory syncytial virus early in life and subsequently determine their role in the development of asthma, airway hyper-reactivity, and allergy. Forty percent of participants will be black. Another study will improve understanding of the etiology of asthma and the response to asthma drugs by performing GWASs to identify genetic factors that are associated with asthma, asthma severity, and bronchodilator response in two Latino subgroups. Additional studies will identify the genes and structural genetic variations that contribute to childhood asthma in the major racial and ethnic groups in the United States and in Hispanic and black populations outside the United States.
An investigator-initiated study is seeking to understand the contribution of social and physical environment factors across neighborhood, family, and individual levels to develop a more comprehensive understanding of the causes of asthma disparities in children.
Investigators are also interested in the role of stress in the development of asthma. One study is using a systems biology approach to determine multiple biologic pathways by which stress can contribute to asthma. Scientists are investigating whether maternal stress immediately before or after the birth of a child can adversely affect the child's risk for wheezing and impair lung function later in childhood. Scientists hypothesize that multiple stressors that are prevalent in disadvantaged populations can cumulatively influence immune system development and airway inflammation in early life, thus making the populations more susceptible to other environmental factors and genetic risk factors explaining, in part, the observed asthma disparities associated with SES and race and ethnicity. Another study is seeking to identify psychosocial factors associated with the incidence of adult asthma onset in black women. A third study is investigating whether risky family behavior—characterized by conflict, neglect, and a lack of emotional warmth and support—is associated with greater asthma morbidity. Most participants are from various ethnic and minority populations.
A group of scientists has speculated that vitamin D deficiency in pregnant mothers may lead to faulty immune system development in neonates, predisposing them to asthma and allergy. To test the hypothesis, scientists will determine whether supplemental vitamin D intake to increase the level of vitamin D in pregnant women will prevent asthma and allergy in their children at age 3 years. More than 50 percent of participants are from racial and ethnic minority populations.
Research findings suggest that obesity and asthma are complex disorders that may have shared genetic determinants. An investigator-initiated study is seeking to identify single nucleotide polymorphisms (SNPs) that are jointly associated with asthma and obesity, using data from the CAMP study, and subsequently validate the SNPs in three independent and diverse (Hispanic, black, and white) cohorts.
Treatment and Control
The Institute has initiated research to identify optimal strategies for treatment and management of asthma. Because the burden of asthma disproportionately affects minority children, it is important for them to be well represented in clinical trials.
Quality of life measures can assist health care providers in treating asthma. Based on recommendations by the Asthma Related Quality of Life Subcommittee of the Asthma Outcomes Workshop held in 2010, new instruments are being developed and tested to measure more comprehensively the effects of asthma on quality of life in a multi-ethnic and multi-racial population.
One way to reduce asthma health disparities is to begin treatment in early childhood. Studies have shown that asthma education programs can improve overall management of asthma in preschool children. A study in Baltimore, Maryland, is partnering with Head Start to compare the efficacy of early intervention plus asthma education versus asthma education alone in reducing asthma morbidity. Nearly all participants will be black. Another study, in a full-scale trial of an entire school district, is using a Web-based screening and communication tool and telemedicine asthma assessments to ensure appropriate follow-up care and optimal treatment of poor children with asthma. Most participants will be black or Hispanic. A third study is evaluating the ability of a school-based asthma stress management intervention for high risk, socioeconomically disadvantaged children living in an urban setting to reduce disparities in asthma morbidity. Fifty percent of participants will be black.
The Institute is supporting several investigator-initiated studies focusing on finding effective treatment for various populations. One study is seeking to improve health among urban black adolescents with asthma by using peer support—enhanced by a culturally sensitive, technology-based MP3 player platform—to increase adherence to daily controller medications. Another study is targeting inner city black adolescents who have moderate to severe persistent asthma to evaluate the ability of innovative home- and community-based psychotherapies to improve treatment adherence and outcomes. A third study is assessing the effects of heart rate variability biofeedback on airway reactivity and inflammation to determine whether biofeedback can be useful for treating asthma. Approximately 35 percent of participants will be from minority groups.
Recent studies have reported that substantial rates of youth exhibit asthma-like symptoms that are undiagnosed. A study targeting underserved inner-city, ethnic minority adolescents who meet criteria for persistent asthma, but who have yet to be diagnosed, is investigating whether a multicomponent intervention (student, caregivers, and medical providers) is effective in helping families obtain a diagnosis and then treat and reduce asthma-like symptoms.
For a subgroup of individuals with severe asthma, standard drug therapy does not control their symptoms. A study is underway in such patients to determine whether treatment with L-arginine can improve their asthma control. Approximately 50 percent of participants will be from various ethnic and racial minority populations.
Many individuals with asthma have poor disease management. An investigator-initiated study is determining whether an intervention designed to stimulate communication between caregivers and clinicians and to contain individualized guideline-based recommen-dations for care, administered in urban primary care offices, reduces morbidity among urban children with asthma. Fifty percent of participants are black. Another study is addressing asthma disparities that persist among high-risk children who live in rural, medically underserved areas by testing a school-based telemedicine approach that will deliver asthma education to rural children with asthma, their caregivers, and school nurses. The approach also prompts the children's primary care physicians with treatment recommendations. Approximately 75 percent of participants will be black. A third study is developing and testing a technology-based intervention to improve asthma medication adherence in urban blacks, aged 18 to 25 years.
A study in high-risk black adolescents with moderate to severe asthma is testing the effectiveness of an intensive home- and community-based psychotherapy intervention to improve asthma management and reduce the number of hospitalizations and visits to emergency departments. Black women will be the target of a study to improve asthma management by using a highly tailored telephone counseling approach to foster a partnership between women and a clinician. A study of obese adults will evaluate the efficacy of an evidence-based lifestyle weight loss intervention to control asthma. Approximately 40 percent of participants will be from minority populations.
Investigators are also interested in evaluating whether cultural competency training for primary care physicians who primarily serve black or Hispanic communities will improve the asthma outcomes of their patients.
Symptoms of depression are commonly found in patients with asthma. A pilot study using an antidepressant to treat outpatients with major depression and asthma showed that patients who received treatment experience greater sustained remission of depressive symptoms and require significantly less oral corticosteroids for asthma management than the group who received placebo. Based on these findings, scientists are implementing a definitive antidepressant study in patients with asthma and major depression. Most participants will be black or Hispanic.
The Institute is supporting several education activities through the National Asthma Control Initiative (NACI), which was developed by the NAEPP and is coordinated by the NHLBI. The NACI works to accelerate the adoption of six priority action messages from the latest asthma guidelines to achieve change in asthma clinical practices and outcomes. NACI Demonstration Projects, Strategic Partner Projects, and Clinical Champions Projects are implementing intervention strategies in racial and ethnic communities to address asthma health disparities in diverse populations. The Institute has developed easy-to-read materials on asthma treatment and control that target English and Spanish audiences with low literacy:
The Institute co-chairs an Asthma Disparities Working Group under the auspices of the President's Task Force on Environmental Health Risk and Safety Risks to Children. In 2012, the Task Force released the Coordinated Federal Action Plan to Reduce Racial and Ethnic Asthma Disparities, which was developed by the Working Group, to maximize the use of existing Federal resources to address asthma disparities. The Action Plan focuses on coordinating Federal activities to promote the adoption of clinical practice guidelines in racial and ethnic communities that are at high risk of poor asthma outcomes, and provides a forum for Federal agencies to collaborate on identifying innovative ways to treat and educate minority children who have asthma and their families and accelerating research on preventing the onset of the disease.
COPD—a disease in which the lungs are damaged, making breathing difficult—is the third leading cause of death in the United States. It is responsible for more than 500,000 hospitalizations and more than 130,000 deaths in the United States each year.
The NHLBI is supporting a study of genetic factors that determine the risk of developing COPD or influence the type and extent of damage done to the body by the disease. The Institute is also supporting a targeted metabolomic phenotyping program in cohorts of individuals with COPD to gain a mechanistic understanding of the pathways operative in COPD.
Although COPD is less common among blacks than among whites, it is nevertheless the seventh leading cause of death among blacks. Any disparity, whether higher or lower in the minority group, may reflect racial differences in the biology of the disease that would require use of different treatments or drugs for optimal disease management. If the genes found to be determinants of COPD risk differ in blacks and whites, this will provide clues to how the roles of specific pathogenetic pathways of COPD differ among races.
Treatment and Control
In collaboration with the Centers for Medicare and Medicaid Services, the Institute is sponsoring a clinical trial of supplemental oxygen treatment in COPD patients:
The NHLBI has developed a number of outreach activities associated with COPD. Several publications and Web-based products have been developed and distributed for health professionals, patients, and the public. Some examples include:
Sarcoidosis is an inflammatory disease of unknown etiology characterized by persistent granulomas with damage to surrounding tissue. The Institute supports research into the basic mechanisms of sarcoidosis and new and improved treatments for it.
Sarcoidosis occurs more frequently and with more severity in blacks than in whites, suggesting the presence of genetic determinants to disease predisposition. To increase understanding of the disease, researchers are seeking to identify genes of African ancestry that play a significant role in its etiology and pathogenesis. Specifically, a new investigator-initiated study will use the next generation gene sequencing technology to detect rare, causal genetic variants of sarcoidosis in blacks. A mentored research project conducted within the Black Women's Health Study is investigating potential genetic and nongenetic risk factors for sarcoidosis.
Diagnostic tools and treatment approaches for sarcoidosis are lacking. A study supported by the Institute-initiated CADET Program (see Chapter 9) is seeking to develop a skin test for diagnosing sarcoidosis and to establish an approach for treating sarcoidosis with oral vaccines. Fifty percent of participants are black. Another study, in a mostly black population, is seeking to identify a panel of antibodies that will recognize sarcoidosis granuloma antigens and thereby aid in the diagnosis of pulmonary sarcoidosis and identification of molecular targets for its treatment.
Sleep-disordered breathing (SDB), a condition characterized by repetitive interruption in breathing, is a common disorder that disproportionately affects blacks. It is associated with an increased risk of CVD, including hypertension and stroke, and is particularly prevalent in patients with heart failure. Ongoing programs are assessing the interrelationship between sleep disorders and heart failure and the mechanisms leading to cardiovascular stress when the two intersect.
The Institute also supports investigator-initiated projects to elucidate cardiovascular and other health consequences of SDB, sleep deprivation, and shift work in various community settings. One study is testing associations between indices of sleep apnea and the quality, duration, and timing of sleep with indices of cardiovascular risk and disease to address the role of sleep disorders in CVD development. Approximately 60 percent of participants are expected to be from racial and ethnic minority groups. Another study is investigating sleep apnea in stroke patients, collecting and analyzing data on prevalence, relationship to ethnicity, and the association between stroke type and outcomes. Approximately 65 percent of participants are from racial and ethnic minority groups.
Scientists are also interested in the effect of sleep apnea on cardiovascular risk in individuals with diabetes. They are investigating the contributory effects of sleep apnea in vascular disease among persons with type 2 diabetes and identifying possible mechanisms through which treatment can reduce cardiovascular risk. Most participants are from racially and ethnically diverse populations.
The current obesity epidemic in the United States is resulting in an increasing prevalence of obstructive sleep apnea (OSA) in adolescents. One study is seeking to elucidate the pathophysiology of OSA in obese teenagers and determine the effect of weight loss on OSA. The majority of participants are black. Another study is determining the effect of sleep restriction on the neurobehavioral and brain function while adolescents are engaged in sustained attention tasks. Sixty percent of participants are from minority populations.
Shortened sleep duration (less than 6 hours) and its negative consequences have been investigated extensively in individuals with SDB. However, despite shortened sleep duration, many individuals do not suffer from SDB. A study in a racially and ethnically diverse population of individuals without SDB is identifying the association between sleep duration and markers of autonomic function, endothelial function, and inflammation.
In an ancillary study to the HCHS, investigators are collecting sleep pattern measures from several Hispanic subgroups. Investigators will analyze the prevalence of altered sleep patterns and define the importance of psychosocial factors (e.g. , home- and work-related factors and mood, as well as cultural factors) in predicting abnormal sleep patterns. They will also evaluate associations between poor sleep and cardiovascular health outcomes, including obesity, hypertension, diabetes, and heart disease.
Treatment and Control
The Institute initiated a pilot study to guide design of phase III clinical trials to test whether treatment of OSA with continuous positive airway pressure (PAP) reduces CVD risk:
Investigator-initiated research will also assess treatment strategies in minorities. One study is developing in-home personalized sleep plans to improve nightly sleep duration, neurocognitive function, and behavioral disorders in lower income minority children (ages 5 and 6 years). Another study will measure effects of continuous compliance to PAP therapy on neurocognitive function (including academic achievement, attention, working memory, decision making, and mental flexibility) in children. Approximately 60 percent of participants will be from minority populations. Parental reports of child behaviors and sleep patterns will also be assessed. A third study will advance understanding of endothelial activation processes in OSA patients and may enable early identification of OSA patients who are at risk for vascular diseases. Approximately 90 percent of participants are expected to be from minority populations. Results may provide the basis for developing new therapeutic strategies for preventing or reversing vascular risk in OSA patients.
Insomnia is a frequently co-occurring sleep disorder that interferes with adherence to OSA treatment. A new study will determine the efficacy of a multidisciplinary treatment that combines cognitive behavior therapy and continuous PAP therapy for patients with OSA and comorbid insomnia in a mostly diverse minority population.
HIV infection disproportionately affects minority populations in the United States. Due to multidrug antiretroviral therapy, HIV has become a chronic condition for many patients. Among them, HIV-associated lung complications are frequent causes of illness and death. But the long-term consequences of HIV infection and HIV-associated lung infections and complications are unknown. Little is known about drug-resistant Pneumocystis, the prevalence and pathogenesis of HIV-associated COPD, HIV-associated pulmonary hypertension, and immune reconstitution syndromes.
In developing countries where millions of people are infected with HIV, many have serious or fatal lung complications, including TB and bacterial pneumonias, that have never been characterized well. Lung diseases and CVD, usually more prevalent in older populations, are having an increasing effect on HIV-infected populations in the United States and other industrialized nations where the average age of HIV-infected individuals has increased due to effective antiretroviral therapy. The effect is exacerbated because lung and cardiovascular complications are occurring in relatively young age groups in HIV-infected populations.
The Institute has initiated research to understand the causes and impact of HIV-related lung diseases and to identify potential therapeutic targets and preventive strategies:
Treatment and Control
The Institute seeks to support clinical trial planning grants in the management of HIV-related lung disease and cardiovascular comorbidity:
An ancillary randomized trial to the Strategic Timing of Antiretroviral Treatment trial is determining whether early antiretroviral treatment of HIV reduces the rate of decline of lung function in HIV-infected individuals.
TB is a common and often deadly infectious disease caused by Mycobacterium tuberculosis. In the United States, an estimated 10–15 million people are infected with the TB bacterium. Although the majority of those infected remain healthy (latent TB infection), a small percentage develops active tuberculosis. The rates of both TB infection and active TB among minorities and in the foreign-born remain high. In 2008, according to the CDC, more than 58 percent of all active TB cases in the United States were among the foreign-born. Racial disparity in TB rates was greatest for U.S. -born blacks, whose rate was 7-times higher than the rate for U.S. -
The immune response to TB infection is complex and involves the formation of granulomas in the lungs of infected individuals. In 2010, the Institute began a systems biology approach to identify the mechanisms of TB latency and reactivation.
The Institute also supports investigator-initiated research that characterizes genes associated with TB susceptibility; investigates host lung defenses, including immune responses to infection; and examines the impact of TB on HIV disease. A genetics study will seek to fine-map chromosomal regions that have been linked to resistance to TB. The study also plans to analyze innate immune responses and model genetic predictors of resistance using data from a long-term household contact study conducted in Uganda.
Treatment and Control
The NHLBI supports a number of investigator-initiated studies to understand the relationship between the immune system and TB. Most of the studies are being conducted in patients from minority populations. One study is seeking new approaches to diagnosing and treating active TB in sub-Saharan Africa and other parts of the world. The study may also identify new markers that can predict response to TB therapy. Another study is determining whether different strains of Mycobacterium tuberculosis cause different responses in individuals from various racial and ethnic groups. Results of this study may increase understanding about tailoring vaccines to specific populations. A third study is testing the efficacy of daily vitamin D supplementation, added to multidrug therapy, to improve antimicrobial immune response to TB infection in residents of Mongolia.
The NHLBI supports basic, translational, and clinical research on SCD and thalassemia (Cooley's anemia) with the goal of curing the disorders and improving patient care. The Institute also supports programs in transfusion medicine, blood banking and blood products safety, and such cellular therapies as bone marrow transplantation.
SCD, the most common inherited blood disorder in the United States, affects an estimated 70,000 to 100,000 Americans, most of whom are black. SCD occurs in about 1 in 500 blacks and 1 in 36,000 Hispanics. The disease is characterized by anemia, severe infections, acute and chronic pain, and organ damage. SCD, the first molecular disease described, was shown to be due to a single amino acid substitution on the beta chain of hemoglobin.
Since 1972, the NHLBI has supported an extensive research program to improve understanding of the pathophysiology of SCD, identify better approaches for its diagnosis and treatment, and prevent complications.
Basic and translational research currently focuses on the neurobiology of pain in SCD:
Investigator-initiated studies are exploring new methods to reactivate fetal hemoglobin expression for the treatment of SCD and thalassemia.
Other investigator-initiated studies are seeking to identify new pathways and regulatory mechanisms that may be as important in the pathophysiology of SCD as red blood cell sickling is itself. One area of interest is the role of the immune and coagulation systems in the vaso-occlusive pathologies associated with SCD. Another area focuses on the role of inflammation and vascular perfusion in SCD. Researchers are using flow cytometry and contrast-enhanced ultrasound to identify new biomarkers of severity of tissue injury related to the state of inflammation and vascular perfusion in adults with SCD. Identifying such circulating biomarkers may help when evaluating the effectiveness of new therapies.
Gene therapy is another area of focus. One project is exploring lentiviral gene therapy for SCD, and another is studying the application of induced pluripotent stem cell technology to replace the defective sickle beta-globin gene with a normal gene in a SCD mouse model. Researchers are seeking to translate their results to human cells that will become the foundation for future clinical trials.
Through the SBIR and the STTR programs, the NHLBI supports translational projects to develop therapeutics and tools that can be used to treat SCD and other hemoglobinopathies. Recent projects are evaluating the ability of retargeted drugs to increase fetal hemoglobin production; testing new agents to produce opioid-level analgesia without the opioid-related side effects for relief of SCD pain; conducting a clinical study of a humanized monoclonal antibody drug for treatment of vaso-occlusive crisis; and developing a Web interface tool that can be used to improve the quality of care received by SCD patients during hospital emergency room visits.
The NHLBI is committed to finding improved treatments and ultimately a cure for SCD and other hemoglobinopathies. Institute-initiated studies, such as hematopoietic cell transplantation, have begun to yield therapies that will alleviate the symptoms of sickle cell anemia and procedures that should ultimately cure the disease.
Often individuals with SCD experience barriers that prevent them from getting appropriate treatment for their disorder or have difficulties adhering to care. One study is employing specially trained SCD patient navigators who address barriers to care and to the use of hydroxyurea. Phase 1 of the study will focus on increasing the percentage of adults with SCD who are in SCD specialty care, and Phase 2 will focus on increasing the percentage of patients who are adhering to hydroxyurea therapy. Another study is developing a patient navigator program for parents of children with SCD to improve adherence to preventive care and overall retention in care.
The Institute supports research to assist hematologists in their ability to assess clinical outcomes. The Adult Sickle Cell Quality of Life Measurement Information System is a useful instrument to assess health-related quality of life among adults with SCD. The instrument has been integrated into an NIH Roadmap Patient-Reported Outcomes Measurement Information System.
Pain is the most common cause of acute morbidity in children and adults with SCD. The Institute has identified acute pain management and prevention as a high-priority area for research in children. One study is developing and evaluating the efficacy of using an individualized pain plan in children at home and in hospital emergency departments. A functional assessment tool is being developed to assess pain and functionality in hospitalized children with SCD.
The Institute is supporting investigator-initiated clinical trials for children with SCD. One trial in children with abnormal transcranial Doppler (TCD) velocities is comparing standard therapy (transfusions) with alternative therapy (hydroxyurea) for maintenance of TCD velocities and reducing the risk of primary stroke. Another trial is seeking to determine the effect of hydroxyurea treatment on the cumulative incidence of conversion from conditional to abnormal TCD velocities.
The NHLBI has developed the Sickle Cell Disease Information Center (http://www.nhlbi.nih.gov/new/sicklecell.htm), a Web site that contains information for the public and health professionals.
In 2012, the Institute initiated the National Blood Disorders Program (NBDP), whose mission is to improve the management of SCD and other blood disorders through collaborations among Federal partners and other stakeholders. Building on the evidence-based Sickle Cell Disease Guidelines (planned to be released by the NHLBI in 2013), the NBDP seeks to improve the health and quality of life in persons who are living with SCD. The Guidelines contain recommendations for youth and adults living with SCD. Topics include health maintenance and care of acute and chronic complications.
Thalassemia is an inherited disorder in which red blood cells with abnormal forms of hemoglobin are produced. The disorder, which results in excessive destruction of red blood cells and anemia, affects primarily people of African, Asiatic Indian, Chinese, Mediterranean, and Southeast Asian origin.
Institute-initiated activities include:
An investigator-initiated study is examining hematopoietic transplantation and gene therapy approaches to cure thalassemia.
The NHLBI supports studies on the use, safety, and availability of blood and blood components for transfusion and cellular therapies that are seeking to reach minority populations:
Investigator-initiated studies seek to generate a concise description of erythropoiesis that unifies genetics, molecular processes, and cytokine determinants in the erythroid lineages so that new therapeutics can be developed to measure and combat anemia. One study is elucidating the mechanism for developmental regulation of globin gene expression with the goal of developing therapies for SCD and beta-thalassemia.