CHAPTER 1
Promoting Lifelong Health for Families and Communities
Every child deserves a bright future, growing in a nurturing family and living in a supportive community. From the moment of conception, individuals grow in physical and relational environments that evolve and influence each other over time and that shape their biological and behavioral systems for life. Dramatic advances in a wide range of biological, behavioral, and social sciences have shown that each child's future depends on genetic predispositions (the biology) and early environmental influences (the ecology), which affect later abilities to play, learn, work, and be physically, mentally, and emotionally healthy. Box 1 provides definitions for several key terms related to the lifelong health of children, families, and communities.
Accumulating research in behavioral neuroscience has shown that an infant's biological heritage interacts with his life experiences to affect the developing architecture of the brain and shown how the systems rewire in response to changes in the environment (plasticity). Basic neuronal pathways lay the foundation for more complex circuits, similar to how developmental skills pave the way for more sophisticated skills. Positive early experiences establish a sturdy foundation for a lifetime of learning, healthy behaviors, and wellness.
Although individual health trajectories vary, population patterns can be predicted according to social, psychological, environmental, and economic exposures and experiences. For example, children and adolescents living in poverty (20% of all US children = 17 years) are exposed to a cluster of determinants of health that result in high rates of infant mortality, developmental delays, asthma, ear infections, obesity, and child abuse and neglect. Research results from numerous scientific disciplines suggest that "many adult diseases should be viewed as developmental disorders that begin early in life, and that persistent health disparities associated with poverty, discrimination, or maltreatment could be reduced by alleviating toxic stress (exposure to severe and chronic adversity) in childhood."
Because of the powerful influence of various determinants of health early in life, the American Academy of Pediatrics (AAP) has adopted an ecobio-developmental model of human health and disease (Figure 1).
The model invites health care professionals to be guardians of healthy child development and to function as community leaders to help build strong foundations for positive social interactions, educational achievement, economic productivity, responsible citizenship, and lifelong health. Partnership with families is key to reaching this goal. This combined focus of efforts will result in preventive care that is more developmentally relevant and that reflects the growing evidence that programs and interventions targeting the early years have the greatest promise and provide the highest return on investment (Figure 2). However, health care professionals cannot be guardians of child health alone. Just as every surgery requires a team working in concert, pediatric health care professionals need a team focused on assessing children's and families' strengths and risks and intervening at various time points across the continuum of care. They also need strong links to community resources that can support the work done in the medical home. Health care professionals need skills and resources to build effective partnerships with families, and families need knowledge and support to become effective partners in achieving these goals.
The Life Course Framework
Life course is a conceptual framework, consistent with the eco-bio-developmental model, that identifies and explains how the complex interplay of biological, behavioral, psychological, social, and environmental factors can shape health across an entire lifetime and for future generations. Bright Futures has adopted the life course framework to help health care professionals understand how these factors influence children's capacity to reach their full potential for health and why health disparities persist across populations. Figure 3 illustrates that higher or lower health development trajectories are influenced by the relative number and magnitude of risk and protective factors. Applying this framework in practice gives health care professionals an unprecedented opportunity to positively influence the future health and well-being of patients and their families.
Pediatric health care professionals have historically focused on development, from birth through adolescence. The life course framework incorporates and expands on this traditional perspective. Fine and Kotelchuck have summarized key life course concepts.
* Health trajectories are largely shaped by events during critical periods of early development.
* The cumulative effect of experiences and exposures influences adult health.
* Biological, physical, and social environments influence the capacity to be healthy by creating risk factors and strengths and protective factors for children and families.
Critical Periods and Early Programming
An important component of the life course framework is recognizing the critical time periods when exposures can have protective or adverse effects on learning, behavior, and future health. Barker notes that "[c]ritical periods for systems and organs are usually brief, and many of them occur in utero." During these periods, certain exposures can change gene expression or activity without altering the DNA sequence. This emerging field of study, called epigenetics, has shown that events during critical periods change the process by which the physical, psychological, and social environments influence the expression of DNA. This phenomenon determines body and brain architecture and function.
Beneficial in utero environments, in which fetuses are nourished, exposed to normal levels of maternal stress hormones, and protected from toxins, provide an environment in which the fetus is able to develop optimally during times when the architecture of the brain is created and full expression of genes occurs. Evidence also shows that adverse experiences before birth have similarly important effects on development but in a negative way. These consequences include diminished physiologic responses (eg, immune system) and altered brain architecture.
Cumulative Effects
The life course literature also stresses that the effects of early experiences are cumulative, influencing health in adulthood. Ongoing adversity in childhood can increase the risk of common chronic diseases of adulthood. Environmental risks, such as chronic exposure to lead, also can be significant. Other adult health outcomes associated with adverse events of childhood include
* Cardiovascular disease
* Obesity
* Type 2 diabetes
* Alcohol or drug use disorder
* Depression
The Adverse Childhood Experiences (ACE) Study (Box 2) has identified many associations between childhood stressors and later negative health outcomes in adulthood. The ACE Study was only the beginning of our understanding of toxic stress, and it is important that health care professionals keep a broader concept of adversity in mind when addressing and caring for children and families. Many other factors can negatively affect a child's developmental trajectory. The AAP defines these factors, or toxic stresses, as "strong, frequent, or prolonged activations of the body's stress response systems in the absence of the buffering protection of a supportive adult relationship."
Moderating Factors
Despite growing evidence about biological embedding and the negative effects of early adverse experiences, studies also demonstrate that caring relationships and improvements in children's environments can do much to moderate adverse effects. Because the biological systems of young children are still developing, carefully chosen positive interventions can offset negative experiences that occur during gestation or when children are very young. For example, foster children who have been hit, shaken, or threatened often do not have normal hypothalamic-pituitary-adrenal (HPA) axis activity. However, several studies have shown that the disrupted cortisol secretion caused by adversity early in life can be reversed by interventions that improve caregiving. For example, early child maltreatment can cause dysregulation of the HPA axis, which can lead to emotional, behavioral, and physical problems. But placing children with foster parents who are taught behavioral parent training techniques can reverse this dysregulation, and children who report strong social supports are less likely to experience the consequent problems of HPA dysregulation.
In another example, every stage of life is affected by nutrition, including the mother's nutrition before and during pregnancy. Efforts to improve maternal nutrition and increase the availability of a variety of healthful food for children can increase the likelihood of health throughout life. Other environmental factors that can be moderated include
* Exposure to chemicals in the home (eg, lead in paint or toys) and in the air (eg, tobacco smoke, industrial pollutants)
* Access to drinking water, whether from a municipal or private source, that meets all established health standards
All families go through difficult times, and factors such as strong and loving relationships, personal resiliency, and adequate support systems also can be important moderating factors to help families withstand these situations. Two families may have similar life circumstances and incomes but may have very different outcomes after a personal tragedy or natural disaster. For example, research has shown that environmental and relational factors played major roles in accelerating or impeding recovery of children and their families affected by Hurricane Katrina. Some characteristics that positively influenced families' ability to cope were pre-disaster functioning, spirituality, social connectedness, and post-disaster consultation with a mental health professional. Factors that made recovery more difficult for children were loss of resources, school problems, and long-term family or community disruption.
Efforts to decrease parental stress, improve parenting, provide safe and predictable routines, and bolster relationships with warm and responsive adults can buffer stressful events and situations and promote healthy development.
The Life Course Framework in Bright Futures
A central concept of the life course framework is that children and families are affected by a variety of biological (ie, "nature") and ecological (ie, "nurture") exposures that can either promote healthy development or increase risk of impairment or disease. Viewing health care through this lens allows health care professionals to identify family, neighborhood, and community determinants that affect the lifelong health of their patients. Recognizing these influences allows health care professionals to tailor their entire scope of practice (ie, screening, care coordination, formulation of treatment plans, and health promotion) to mitigate the risks that imperil a child's current and future health and promote the strengths and protective factors that secure a child's current and future health. The life course framework also encourages families, in collaboration with health care professionals, to seek support from community and other resources outside the practice to create a family-centered, culturally and linguistically competent, community-oriented, team-based medical home that promotes robust health in children within the context of their families and communities.
The goal of Bright Futures is to support a life course in which the strengths and protective factors outweigh the risk factors. To support this goal, the next 2 sections provide greater detail on the biological and ecological determinants that so profoundly influence child and family health. This discussion allows health care professionals to actively promote strengths and protective factors by assessing determinants of health within the scope of their practice.
Biological Determinants
A child's development is initially determined by the genes inherited from both parents, the expression of which can be altered in utero. A child's life course can be optimized even before birth by excellent nutrition from a healthy mother and a uterine environment that allows full expression of genes.
Conversely, the likelihood of optimal development is negatively affected by a stressed or depressed mother, intrauterine exposures to toxins, poor nutrition in utero, and birth trauma. Certain toxins affect fetal development. For example, exposure to lead, found in lead-based paints, soil, dust, and some toys, is a known danger to healthy cognitive development. Drinking alcohol during pregnancy is one of the leading preventable causes of birth defects, intellectual disabilities, and other developmental disabilities in infants, children, and adolescents. Babies born to mothers who smoke cigarettes are at higher risk of being born early, having a low birth weight, having an orofacial cleft of the lip or palate, or experiencing a sudden unexplained death during infancy. Many of these determinants have been well-known for decades, and anticipatory guidance includes screening for them and counseling parents about them.
Emerging science has shown powerful and previously unknown effects of gestational influences on adult health, which go far beyond inherited genes and personal choices. Figure 4 illustrates that if early childhood experiences are protective and personal, adaptive or healthy coping skills are more likely. If early experiences are insecure or impersonal, maladaptive or unhealthy coping skills are more likely. For example, recent research on the toxic effects of maternal stress and depression illustrate in utero biological determinants of health.
* Children exposed to normal levels of maternal stress usually develop the ability to have appropriate reactions (ie, mild and brief) to stress, especially when supported by caring and responsive adults who help them learn to cope. However, when a fetus is exposed to high levels of maternal stress, the developing architecture of the brain is disrupted, which results in a weakened foundation for later learning, behavior, and health.
* High cortisol levels in the mother during pregnancy also can disrupt development of the immune, inflammatory, and vascular pathways, setting the stage for adult diseases decades after the exposures.
* Expectant mothers who live in stressful environments tend to have lower-birth-weight babies, putting the child at risk for numerous conditions later in life.
* Inadequate nutrition at certain time points in pregnancy results in elevated risks for adult diseases decades after birth. Low-birth-weight babies are at risk of having obesity during childhood and for hypertension, cardiovascular disease, and stroke as adults.
* In addition, very low-birth-weight babies are often born with insulin resistance and other metabolic changes that put them at risk for developing diabetes later in life.
* Maternal depression during the third trimester is epigenetically associated with later increased infant stress responsiveness.
