In the Swedish study, the risk for cardiovascular problems for
adults who had been in very adverse early child circumstances in
comparison to those who were in good environments for child devel-
opment was 7:1. The risk for mental health problems, such as depres-
sion, was 10:1. The data concerning depression in this study are com-
patible with what we are beginning to understand of how poor early
child development can alter gene expression in relation to serotonin
transport, which can influence depression. The odds ratio for mortal-
ity for those brought up in the poorest environments was twice that
of children brought up in good circumstances.
These observations are compatible with our increased understanding
of how experience and brain development in the early years can affect
pathways that affect emotions, behavior, and vulnerability to depres-
sion as well as coronary artery disease.Studies using data from the United States from the National Health
Interview Survey, the Panel Study of Income Dynamics, the Child De-
velopment Supplement, and the Third National Health and Nutrition
Examination Survey have shown that the population health socio-
economic gradients in health can be detected early. Socioeconomic
gradients in health could be detected by age 3 years, and the steep-
ness of the gradients increased as the population became older.
This evidence is important since it shows that the gradient in
health status in adults has its antecedent in early childhood. These
findings are remarkably consistent with what we now know about
the development of the brain in the early years and its effect on phys-
ical and mental health in later life.
A key conclusion is that if we wish to improve equity in health, in-
vestment from a public health perspective in the early years of life
(prenatal and postnatal) is important. Also it is possible to spot signs
and symptoms of poor early development and take steps to improve
outcomes.There have been a series of studies over the past 20 years showing
that conditions in utero have a significant effect on physical and
58 J. Fraser Mustard