Health Disparities Working Group Meeting: Cognitive and Emotional Health In Minority Children
July 23-24, 2001
Hyatt Regency Hotel, Bethesda MD
Sponsored by the National Institute of Neurological Disorders and Stroke:
Systems and Cognitive Neuroscience Cluster
Office of Minority Health and Research
Health disparities, as defined by the NIH, refers to differences in the incidence, prevalence, mortality, and burden of disease among specific racial and ethnic minority populations in the United States. Some of the factors that contribute to these disparities include increased risk of illness due to underlying biological or socioeconomic factors, increased exposure to environmental pollutants, or reduced access to health care. To address some of these issues, the NIH has focused attention on additional basic research, building research infrastructure at minority institutions, and improving public information and community outreach.
Cognitive and emotional health of children is one of 10 areas that NINDS has included in its strategic plan to reduce health disparities (Stroke, HIV, Neurological Complications of Diabetes, Epilepsy, Injury to the Developing Brain, Management of Chronic Pain, Research Capacity Building, Outreach Activities and Inclusion Policies of Minorities in Research). This workshop brought together experts from a wide variety of disciplines to discuss health disparities in the cognitive and emotional health of minority children, identify unmet scientific needs, prioritize research opportunities and develop a plan of action.
Following 6 brief presentations, the participants were divided into 2 working groups. One group discussed the effects of environmental and pharmacological pollutants on cognitive and emotional health in minority children, while the second group discussed the impact of psychological stressors on the same parameters. On the second day, a joint session of both groups consolidated major discussion points.
There are health disparity issues in many minority children irrespective of socioeconomic status, gender, race or ethnicity. One major obstacle to approaching health disparities is the lack of articulated, consensual definitions of cognitive and emotional health. Therefore, there are major gaps in our knowledge about the incidence and prevalence of health disparities in minority children. Within that context, an added difficulty is the broad domain of questions that lie at the interface of biomedical sciences, social and behavioral sciences. The 2001 National Research Council report titled: "New Horizons in Health - An Integrative Approach", provides an excellent framework for the development of research initiatives that address the issues of health disparities in cognitive and emotional health of minority children. The success of such initiatives is highly correlated to the integration of information from the molecular and cellular level with psychosocial and community levels. This concept was emphasized at the NINDS Working Group Meeting on Health Disparities in Cognitive and Emotional Health in Minority Children with the guidance and expertise of Bruce McEwen (Rockefeller University), a member of the Committee on Future Directions for Behavioral and Social Sciences Research at the National Institutes of Health and participant to the present working group meeting.
III. Scientific Presentations
A. Environmental Factors and Brain Plasticity
Ellen Silbergeld (University of Maryland) presented an overview of the effects of environmental pollutants, using lead as an example. The talk focused on the disparities in the sources and pathways of lead exposure resulting in unequal distribution of exposure and the non- optimal outcomes associated with that exposure. Lead poisoning is closely associated with other risk factors, such as low birth weight, in utero exposure to drugs of abuse and adverse early life experience. Lead exposure comes primarily from lead-based paint; children are particularly at risk due to the ingestion of paint chips and dust through
normal hand and mouth activity between the ages of 6-18 months. Lead is also found in garden soil in high traffic areas due to the use of leaded gasoline, in dumping sites with lead contamination, and in lead smelters and recycling facilities that are disproportionately located in minority neighborhoods. Lead crosses the placenta, as does mercury, polychlorinated biphenyl compounds (PCBs) and dioxins. Therefore, immediate effects of exposure to lead can be seen in the development of the nervous system, skeletal system, and cardiovascular system. Long- term effects can be seen in cognitive function and behavior. Epidemiology studies have shown an association between early exposure to lead and aggressive behavior patterns and deficits in performance in intelligence tests. Moreover, long- term effects of lead exposure are correlated with a three fold increased risk of hypertension or cerebral cardiovascular incidents in adulthood. Research on the basic biological mechanisms of lead poisoning has pinpointed the interaction of lead with several neurotransmitter systems, but the mechanisms by which specific deficits develop is still not understood. Intervention strategies are few; a trial utilizing the lead chelator Succimer demonstrated a decrease in lead blood levels but failed to show a reversal of the effects of lead on cognition. However other studies are testing the hypothesis that nutritional supplements may lessen or reverse the effects of lead. It is clear that the prevention, and elimination of the various sources of lead are a very high priority.
Mary Blue (John Hopkins University) discussed the specific effects of lead on cortical development. Although a number of studies have demonstrated that a decline in intelligence is closely correlated with lead levels in two-year-old children, the neurobiological mechanisms mediating this decline are largely unknown. In animal studies, low levels of lead exposure in the first postnatal month, cause changes in long-term potentiation (LTP). Lead increases spontaneous electrical activity and receptor-dependent signaling in neurons. This activity in turn influences the development of neural circuitry, and ultimately higher brain function. Dr. Blue and colleagues hypothesized that neonatal lead exposure in rodents would alter the development and plasticity of the cortical barrel field, a part of the somatosensory cortex. The cortical barrel field has proven to be a very useful animal model system for brain plasticity and it allows the study of cortical development during critical periods of development. Exposure of rat dams to lead acetate (0.5-2.0 g/L) in their drinking water from P1-P10 led to pups with significantly smaller barrel sizes. A dose dependent decline in the barrel field size was correlated with exposure to increasing levels of lead and an increase in glutamate receptor activity. In a second experiment, when rat dams were given 0.2% lead acetate in drinking water from P1-P10, changes in brain plasticity were evident in the pups, following denervation of specific rows of the cortical barrel field. These findings suggest that exposure to lead disrupts the normal competitive interactions that are involved in cortical plasticity.
Bertram Payne (Boston University) provided a second perspective on brain plasticity and brain adaptability. His presentation focused on lesions of the cat primary visual cortex as a model system for understanding how the brain changes with insult. Dr. Payne and colleagues assess the types of neural processes and behaviors that are spared and those that are permanently impaired, after injury. The parietal-visual cortex is a part of the brain involved in motion and spatial processing, while the temporal-visual cortex is involved in pattern recognition. These areas of the brain are considered part of the secondary visual cortex. In the adult cat, the secondary visual cortex suffers major losses after lesions to the primary visual cortex. However, if the lesions are performed in the neonate, the resulting deficits are not as severe. Lesions of the primary visual cortex on P1 or P28, results in an overall degeneration seen in all areas of visual cortex, but expansion and rewiring also occurred in secondary visual cortex. Thus some functions are spared after insult to the brain early in life, and regrowth and repair can also take place. Specific functions of the normal cerebral cortex can be remapped across the cortical surface and the response of a young brain to an insult is unique because of the enormous potential to modify connections and rewiring contributing to neural compensations and behavioral outcomes.
B. Psychosocial Factors
Cheryl Boyce (NIMH) gave an overview of the effects of psychosocial stressors on cognitive and emotional health. As the chair of the NIH Child Abuse Neglect Workgroup, she emphasized the problem of inadequate definitions in the field of neglect. Classification of neglect and abuse are not standardized, and coding of severity is a particularly sensitive issue. In recognition of the problem, the Child Abuse Neglect Workgroup held technical assistance workshops to develop a uniform coding system for physical injuries. In addition, the Workgroup has also held technical assistance workshops to encourage researchers to initiate research programs in the area of neglect through career development awards in child abuse and neglect. An RFA on child neglect has awarded 15 grants, ranging from the use of different models to test the reasons for the disparity in reports of child abuse and neglect, to investigations on the neural basis of the parental response to infant crying. The hope for the future is in developing good definitions and assessments, and applying them in longitudinal studies with good clear methodology.
Juanita Dimas (Alameda Alliance for Health) discussed the potential causes of health disparities, and the role of various social and cultural factors. In examining psychological adjustment among Latino adolescents, she assessed basic demographic variables for their predictive value, as well as cultural variables such as acculturation and ethnic identity. Both acculturation and ethnic identity were highly predictive, and were correlated with a variable coined "public identifiers", which in this case were last name (Spanish or English) and appearance (Latino or not). In other studies that examined outcome within the same ethnic group, or within the same socioeconomic stratum, acculturative stress and minority status stress (experience with discrimination) were predictive. Dr. Dimas proposes some ways to address the causes of health disparity. For example, she recommends that medical care be provided in the native language of the patient, that doctors be trained in cultural competency, and to simply preserve ethnicity information on medical forms so that the existence (or not) of disparities can be tracked.
Gayle Porter (American Institutes for Research) provided some data that identify the highest rates of traumatic experiences, negative experiences, conduct disorders, and levels of abuse and neglect in African-American girls as compared to Hispanic, Asian, and Caucasian girls in a study of children referred for mental health services. African-American girls also were more likely to be the victims of repeat rape, and homicide was their leading cause of death. For the most part these negative exposures were also true for African-American males. Higher rates of exposure to these negative factors affected not only mental and emotional health, but also seemed to correlate with higher rates of diseases such as stroke, emphysema, diabetes, or heart disease in adulthood.
Overall, the two working groups, regardless of whether they were discussing the impact of environmental or psychological stressors, reached consensus on many issues independently. Brief summaries of major discussion points are given below. If a particular item was brought forward primarily by one working group, it is so indicated.
A. Data Collection:
All meeting participants recognized that a reliable baseline data on the cognitive and emotional health of minority children is incomplete, and longitudinal studies that follow children for more than a few years are rare. Information on the health status of different demographic groups needs to be gathered. To be maximally useful, this data should
disaggregate race, gender, and socioeconomic status. Comprehensive longitudinal studies were recommended, with the following variables to be considered:
Retrospective studies to link early childhood exposure with adult onset dementias and other disorders found predominantly in minority populations were considered important, as were studies to investigate the effect of exposure to various contaminants at different developmental periods in humans.
Group 2 (psychosocial factors) discussed some of the barriers to obtaining good data, including a lack of definitions and common terms among workers in the field and a general lack of trust within the community being studied. Many examples were provided that illustrated the importance of involving the community at risk in both the research and the subsequent steps taken to ameliorate a risk situation.
In general the development of research programs on health disparities is hampered by a lack of correct definitions and appropriate assessments. Specifically, researchers need to adopt standardized definitions for the emotional and cognitive domains that are evaluated. Many of the issues, as well as the terms used to describe them, are highly sensitive. As one of the working group participant, Kathleen Westcott pointed out, "There has got to be a way to talk about this without supporting stereotypes..."
Group 2 (psychosocial stressors) highlighted misdiagnosis as a pervasive problem. Behavioral or psychological symptoms in minority children are not always probed to find out if there are underlying cultural issues such as language, self-image, or other culture-specific stresses. Thus these children may be over-medicated while the root problems persist.
There was overwhelming consensus that new assessment tools need to be developed. These assessment tools should be at least culture-neutral, since many of the tests currently used are biased against ethnic populations. Multiple indices of learning and memory should be assessed, as well as spatial and non-spatial learning. Functional brain imaging might be very informative, and ought to be exploited especially in the case of children with brain injury or children exposed to environmental contaminants.
Outcome measures need to be tailored to the group being studied, since what is relevant for one group of children may not be relevant to another. For example, in some Native American populations a highly relevant measure is the percent of children in satanic cults, a question that is not usually asked on most tests.
Group 2 (psychosocial factors) also discussed the alarming homicide rates in minority youths and the potential contributing psychological stressors. The group recognized the importance of various factors, such as strong support networks, physical activity and spirituality, which lead to resilience as compared to vulnerabilities to these stressors.
C. Basic Science
Several areas of neuroscience research were considered especially relevant for understanding differences in cognitive and emotional health in minority children.
The participants propose that NINDS encourage research on the impact of exposure and the critical period of susceptibility to environmental contaminants on higher brain functions that underlie complex behaviors such as learning, memory, attention, language, cognition, emotion, movement and response to pain. In addition, information about susceptibilities to environmental agents should be investigated in order to better understand and ameliorate the excess risk of minority children. While environmental contaminants are not the sole contributors for health disparities in cognitive and emotional health among minority children, studies of gene-environment interactions are extremely important and such studies could be undertaken and completed in a reasonable time period.
Other potential research questions include the effects of environmental and psychological insults on the physiological changes associated with puberty. While it has been documented that African American girls exhibit a significant earlier onset of puberty, there have been no systematic investigations of potential contributing factors and corresponding impact on brain function and behavior. Moreover, there have been few investigations of brain changes associated with post-traumatic stress disorder, attention deficit disorder and differences in drug metabolism in minority children. As the genes involved in various disease processes are identified, the existence of allelic variants among different ethnic populations should be identified, and population based studies of gene-environment interactions in disease etiology should be fostered.
The collection of biological samples from ethnic populations was discussed at length. While the participants of the meeting fully recognized the difficulties and barriers to obtaining biological samples for biological and genetic markers in minority children, the overwhelming consensus was that there was a pressing need to fully investigate the disparities in cognitive and emotional health in this population. However, the participants recommended that a task force be established to fully address the ethics, the type of sample and the ease with which it could be obtained, the cost, and the exact neuropsychological tests that would be administered in these studies.
D. Risk Factors
Some of the risk factors that contribute to health disparities in cognitive and emotional health in minority children were identified as follows:
The contribution of these factors, individually and in combination, should be studied. Since risk factors rarely occur alone, there was particular interest in studying combinations of risk factors. For example, the cognitive effects of lead exposure along with cocaine use would be very informative, since these two risk factors are frequently associated.
Working group 2 (psychosocial factors) stressed the existence of heterogeneity within minority groups. Even if a particular minority population is at higher risk, some children are able to cope better than others. From this observation the idea of resilience has developed, and it would be important to fully characterize successful coping strategies within the population at risk.
Group 1 (environmental factors) emphasized the importance of educating the community about health risks, since so many environmental risks are preventable simply by avoiding them. Community outreach programs are especially valuable. It was noted that early interventions during key developmental periods were important; and that teaching parenting skills improved not only health outcome but also a host of other factors.
A second educational goal is to increase and improve mentorship programs starting in the early elementary grades through college level, with the goal of increasing the cultural diversity of practicing health professionals.
Third, training in cultural competency should be provided to health professionals, so that they have the knowledge and skills to provide care in a culturally sensitive way. The effectiveness of this training should also be objectively measured to determine if health outcomes are improved.
F. Multidisciplinary, Multiagency Approach That Involves Community
The meeting participants recognized that the complexity of the issues underlying health disparities would be best addressed by a multidisciplinary, multiagency approach. For example, the McArthur networks were discussed as a possible model, where experts from different disciplines are given the resources to meet over several years to discuss and brainstorm about how to solve a problem. Some NIH Institutes have funded working groups that are similar in concept to the McArthur networks. These groups are funded for several years, bringing investigators from different disciplines together to identify promising new approaches, generate pilot data, and ultimately submit competitive multi-investigator as well as single investigator grants. The participants strongly recommended that the NINDS develop similar models.
Involvement of the target community was considered extremely important. When community leaders joined with researchers, the quality of the data was much better, and the measures that were developed to handle the risk situation were more appropriate. The example of work with the Mohawk tribe was given. Community leaders were involved from the early stages of research design, they approved the final procedures to be used, and they indicated what steps they wished to see implemented should the data so indicate. The study was very successful, the researchers got the data they needed and the tribe learned how to help themselves, having decided to follow-up and get more funding once the formal part of the study was completed.
Exit strategies should thus be incorporated into any research program where a community is involved, so that the community will be empowered to continue after the researchers go home. This helps to ensure that a community, after a period of intense study and debate, can continue to make positive changes instead of being forgotten after the study is completed.
The meeting participants also discussed the advantages of NINDS partnerships with various service federal agencies. The Substance Abuse and Mental Health Services Administration (SAMHSA) and the Health Resources and Services Administration (HRSA) have existing programs to promote youth development, maternal and child health and community outreach. A working collaboration with agencies with expertise and commitments to the health outcome of children would be beneficial in addressing the problems of health disparities in minority children. Moreover, the meeting participants also exalted the NIH to foster partnerships with non-profit foundations (e.g., Annie E Casey Foundation, New Horizons for Learning, George Lucas Educational Foundation, etc.), that are devoted to the well-being of children and the promotion of innovative educational paradigms.
In order for NINDS to further its goal of funding research pursuant to the improvement of cognitive and emotional health in minority children, a change in funding structure, education, and institutional culture was recommended to support integrative and multidisciplinary studies on the cognitive and emotional health in minority children.
The overarching need is for the support of research on the development of neutral and/or culturally sensitive assessment tools, community based research, and multi-site longitudinal studies. The implementation of these objectives would be best served by the continued activities of chartered working groups. The following recommendations were agreed upon by both Working Groups:
Last Modified April 12, 2011