Free market capitalism, social accountability and equity in early human (child) development

A University of Chicago Nobel Laureate in economics, RW Fogel, and a Dutch economist, JW Drukker, found that as the wealth of Western countries improved following the Industrial Revolution, life expectancy increased and the mean height of their populations improved (1,2). Since height is a product of genes and nutrition, they concluded that improved health was related to improved socioenvironments and better nutrition of children, not improvements in health care.

Today, the health of populations in developed countries is a socioeconomic gradient. These health gradients (3) are linear, which means that whatever the socioeconomic factors influencing health today are, they affect everyone in society, including the wealthiest. The effect, however, is greatest on the poorest members of society.

The Canadian Institute for Advanced Research’s (CIAR) population health program led by Robert Evans (University of British Columbia [Vancouver, British Columbia]) examined the factors contributing to the health gradients in Canada and other countries. They concluded that in the United Kingdom, Canada and the United States (US), the major factor contributing to inequities in health was more than poverty and a lack of health care (3).

Hertzman et al (4) – members of the CIAR’s population health program – proposed that the socioeconomic conditions in early life affected adult health (physical and mental) throughout life. They and others suggested that the development of the brain and related biological pathways in early life were important factors. This led to the hypothesis that if the socioeconomic gradient in health was influenced by brain and biological pathway development in the early years, it was possible that there were similar socioeconomic gradients in education and behaviour (5). The CIAR established a program in human development to explore the concept. The scientists in this program found that the socioeconomic gradients in literacy, numeracy and behaviour were similar to the health gradients (6). They suggested that the effect of experience in early life on the development of the architecture and function of the brain was important in contributing to inequities in health and education.

In 2002, the CIAR established a new program, ‘Experience-based Brain and Biological Development’ to study how genes and experience shape brain development that influences health, learning and behaviour trajectories throughout life.

DEVELOPMENTAL NEUROBIOLOGY

Developmental neurobiology research provides insights into how early development can set socioeconomic trajectories for life in health, learning and behaviour (7). The function of neurons is not just produced by their genes (nature), but also by experiences in early life (nurture). Experience in early life includes adequacy of nutrition; quality of water and sanitation; stimuli such as touch, sound, vision, drugs and injury; and diseases caused by viral and bacterial infections. The effects of early experience on neuron function and neural pathways in early life affect the architecture and function of the brain.

Experience-based brain development in early life affects:

• Emotion;

• Temperament;

• Social functioning;

• Perceptual and cognitive ability;

• Mental health and behaviour;

• Physical health;

• Physical activity such as skiing, swimming, hockey, etc; and

• Language, literacy and numeracy capability.

We now understand how experience can activate and modify the function of normal DNA in neurons. Developmental neurobiology research explains how epigenetic processes are affected by experience that can modify how genes function. Szyf et al (8) studied the development of the neurobiological pathways in rats that affect behaviour (the limbic hypothalamic-pituitary-adrenal pathway). Their research showed that the intensity of the rat mother’s licking of her pups in the first six days affected the function of the hippocampus and the behaviour, memory and capability of the pups as they matured. The hippocampus is an important regulator of the stress pathways that influence glucocorticoid (human – cortisol: rats – corticosterone) blood levels. Cortisol affects the brain (emotions and behaviour) and other organs every day. Szyf et al (8) found that rat pups that are poorly licked by their mother’s in early life have methylation of the cytosine base in the DNA of the genes that regulate the production of the glucocorticoid receptor in the hippocampus (epigenetics) (9). This depresses the function of the gene, leading to reduced glucocorticoid receptor availability in the hippocampus. Thus, the body loses a pathway that helps regulate the levels of glucocorticoids (cortisol) in the blood. Cortisol affects tissues throughout the body, including the brain. Excess cortisol can be damaging to cells and can contribute to poor health.

Another example of gene-environment interaction and epigenetic processes comes from studies of the New Zealand Dunedin birth cohort. Caspi et al (10) found that adverse conditions in early life led to increased risk for depression in adult life for individuals with the short gene structure for the serotonin transporter gene. Those with the long gene structure who were brought up in an adverse environment were resilient. Those with the short gene structure who were brought up in good caring environments were not at an increased risk for depression.

SOCIOECONOMIC FACTORS AND EQUITY IN HUMAN DEVELOPMENT

One of the questions that arise from all these studies is, ‘What is the relationship between factors influencing the social environment and early human development and equity in health and cognitive functions, such as literacy, and noncognitive function, such as behaviour?’. A study (11) by the US Department of Education on adult (16 to 65 years of age) literacy, based on the Organisation for Economic Co-operation and Development population literacy studies, found that approximately 50% of the US population were at levels 1 and 2 (low). Fifty per cent of the population at level 1 had major health problems (mental, emotional and chronic disease). Less than 2% of the population at level 5 (high) (5% of the population) had health problems. Literacy was also a socioeconomic gradient. Health was a gradient when plotted against the literacy capability of the population. This relationship between literacy competence and health is not unexpected in view of what we now know about how experience affects brain development in the early years, and sets brain and biological pathways that affect health and cognitive and noncognitive functions.

Data from birth cohort and population studies (12-14) show that adverse human development in early life leads to poor cognitive function and behavioural and health problems (physical and mental) in later stages of development.

One of the most robust studies showing the critical importance of early human development comes from studies of Romanian orphanages. Studies (15–17) in the US, Canada and the United Kingdom have examined the effect of adoption time on the development of these children. Children adopted into Canadian middle-class families within four to six months of birth showed better development than those adopted later (16). The children adopted eight or more months after birth had abnormal brain development, low metabolic activity in the brain and abnormal electroencephalographies. These children showed significant behavioural problems, such as attention-deficit hyperactivity disorder and antisocial behaviour. The children who were adopted later had lower IQ scores than the children adopted early. In an American study (16) of children in Romanian orphanages, children placed in a fosterparenting program in Romania were compared with those who remained in the orphanage. The striking finding from this study was that the noncognitive and cognitive development of the children who remained in the orphanage was markedly below that of children who were removed from the orphanage and placed in foster care in Romania.

EARLY CHILD DEVELOPMENT AND SCHOOL PERFORMANCE

In terms of school performance, there is now substantial evidence that children who have poor development from birth to six years of age tend to not perform well in primary schools. Hertzman et al’s (22) study of child development in British Columbia at the time children enter kindergarten, found that children who did poorly when tested with the Early Development Instrument at school entry did not do well in the grade 4 language literacy and numeracy tests. In a New Zealand study (20), researchers found that the ability of children at the time of school entry basically determined how well most students performed in literacy and mathematics up to 14 years of age within the school system. The schools did not significantly enhance the performance of the majority of the children who showed poor development at the time of school entry.

Small randomized, controlled trials (23,24) in the US showed that high-quality early human development programs substantially improved school performance and reduced behavioural problems in the school system and in adult life. The Council of Early Child Development in Canada recommends the establishment of early child development programs integrated with the primary schools (25).

SOCIETIES AND SOCIOECONOMIC CHANGE

Societies with equity in health, learning and behaviour tend to be societies that have good caring and supportive social environments for families with young children. The Scandinavian countries have high-quality early child development programs and a high-performance level in literacy and health (26). They can be considered as free market capitalist countries with social accountability. Another country that shows good health and literacy measures is Cuba (27). The Cuban government operates a noncompulsory program in early human development that begins with pregnancy and is extensively used by most families with young children (28).

EQUITY AND SOCIAL ACCOUNTABILITY

Social investments by societies for different age groups show considerable country variation. Lynch (29), in a study of resource allocation for the different age groups, found that in the US, the allocation for early human development was much less on a per capita basis than the allocation for the older age groups. In Scandinavian countries, support for families and young children is much better than in Canada and the United States. The Scandinavian countries also provide good health care and other support for the elderly.

The quality of societies and their equity in health and education is strongly influenced by the public policies that affect early human development. In today’s world, with exponential growth in new knowledge and in new technologies, there is increasing competition for talent (30). The National Academy of Sciences (USA) concerned about this problem has recently released a report by Augustine (31) entitled, ‘Is America Falling Off the Flat Earth?’. He stated that “only providing leading edge human capital, can America continue to maintain a high standard of living – including providing national security – for its citizens”. He argued that America must repair its kindergarten to grade 12 educational system. He identified a problem, but failed to take into account that early human development influences the course of children in the education system, and that America underinvests in the younger generation. Heckman (32) concluded that to improve the quality of the US population (health, education and behaviour), the country must increase investment in the early years of human development. The cost to individuals in Canadian society of mental health and addiction problems, and crime and violence related to poor early human development, is orders of magnitude greater than putting in place quality early child development programs (14,33).

A challenge for all societies, including Canada, as they address the effects of growth in new knowledge and technologies, economic change and globalization, is how to ensure equity in early human development for all families with young children.

The recent World Health Organization Commission on the social determinants of health in the section on early human development in the chapter, ‘Equity from the start’, concludes:

Early childhood offers huge opportunities to reduce health inequities within a generation. The importance of early child development and education for health across the lifecourse provides a strong imperative to start acting now. Inaction will have detrimental effects that can last more than a lifetime. A new approach is needed that embraces a more comprehensive understanding of early child development and includes not just physical survival but also social/emotional and language/cognitive development. This approach should be integrated into lifelong learning (34).

They recommend a course of action for governments:

Governments build universal coverage of a comprehensive package of quality early child development programmes and services for children, mothers, and other caregivers, regardless of ability to pay.

To achieve this goal, as has been emphasized in many reports (13,14), we need to establish high-quality, accessible, available, affordable early child development and parenting programs for families with young children linked to the primary schools as in Scandinavia and Cuba. The state of South Australia (14) has initiated a plan to do this.

Paediatrics, along with other members of the medical profession, can help promote the development of programs to improve early human development in their communities and nationally. Can we as a society sustain our free market economy and also meet our social accountability for early child development?