introduction
research into social inequalities and health has tended to focus on low socioeconomic status in adulthood as the main causal variable, cardiovascular disease as the main outcome variable, adults’ stress experiences as the main mediating mechanism, and redistribution of income among adult workers as the solution.1previous research documenting significant but modest correlations between measures of low childhood socioeconomic status and adult health3–6 has been interpreted as suggesting that the experience of disadvantage during childhood could have small—albeit long-lasting and harmful—effects on adult health.
methods
sample
participants were members of the dunedin multidisciplinary health and development study —a longitudinal investigation of health and behaviour in a complete birth cohort.1the study members were born in dunedin, new zealand, between april, 1972, and march, 1973.
variables
socioeconomic circumstances in childhood and adulthood
infant health
adult physical health
adult dental health
adult mental health and substance use
statistical analysis
regression analyses were used to test the hypothesis that low childhood socioeconomic status predicts poor adult health.
results
all physical health measures at age 26 years, except systolic blood pressure, showed a graded relation with childhood socioeconomic status (table). as socioeconomic status increased, body-mass index and waist:hip ratio decreased and cardiorespiratory fitness increased. the adverse associations with low childhood socioeconomic status remained significant after controlling for infant health, and after adding statistical controls for contemporaneous adult socioeconomic status.all dental health measures at age 26 years also showed a graded relation with childhood socioeconomic status. as socioeconomic status increased, the amount of plaque and gingival bleeding, and the proportion of individuals with periodontal disease and decayed surfaces,decreased. the adverse influence of low childhood socioeconomic status was seen after controlling for infant health and contemporaneous adult socioeconomic status. additionally, the results showed that low adult socioeconomic status had a significant effect on poor adult dental health after controlling for low childhood socioeconomic status.
discussion
this life-course study, spanning the period from birth to age 26 years, shows that low childhood socioeconomic circumstances have long-lasting negative influences on adult health, irrespective of what health cache one begins life with, or where one ends up in the socioeconomic hierarchy as an adult. specifically, the findings document that the social gradient in health—which has been amply documented among middle-aged and older adults—actually emerges in childhood. whereas clinical and research interest in the social gradient has been generated mostly by studies of adults, the findings from this study suggest that the social gradient must be scrutinised in paediatric and adolescent populations as well. further, whereas most studies of the social gradient have narrowed their attention to specificdiseases, such as cardiovascular diseases, we document that the social gradient is far moreubiquitous and troubling. low social class adversely affects many areas of people’s health,including their physical, dental and mental health.
