摘要：Objectives. We examined the relationship between childhood and adult socioeconomic position (SEP) and objectively assessed, later-life functioning. Methods. We used the Medical Research Council’s National Survey of Health and Development data to examine performance at 60 to 64 years (obtained in 2006–2011) for a representative UK sample. We compared 9 physical and cognitive performance measures (forced expiratory volume, forced vital capacity, handgrip strength, chair rise time, standing balance time, timed get up and go speed, verbal memory score, processing speed, and simple reaction time) over the SEP distribution. Results. Each performance measure was socially graded. Those at the top of the childhood SEP distribution had between 7% and 20% better performance than those at the bottom. Inequalities generally persisted after adjustment for adult SEP. When we combined the 9 performance measures, the relative difference was 66% (95% confidence interval = 53%, 78%). Conclusions. Public health practice should monitor and target inequalities in functional performance, as well as risk of disease and death. Effective strategies will need to affect the social determinants of health in early life to influence inequalities into old age. In 2012, the World Health Organization (WHO) made health and aging the theme for World Health Day, 1 a timely reminder that the striking increase in human longevity should give cause for celebration, 2 especially when “good health adds life to years.” 1 However, population aging is often framed in negative terms because of its anticipated societal effects, perhaps most prominently in terms of health and social care spending. The societal impacts of aging depend on health and functional capability. These vary considerably between individuals, but the extent to which inequalities in health and function in later life are driven by early life exposures is less well understood. There is growing interest in the impact of adverse earlier life experiences—already shown to be associated with inequalities in subsequent chronic disease risk 3 —on levels of functioning in later life. 4,5 Maintenance of physical, cognitive, psychological, and social function for the maximal period of time is a key feature of healthy aging. 6 Higher levels of physical and cognitive functioning are associated with continued independent living, 7 a higher quality of life, 8 and lower rates of subsequent morbidity and mortality. 9–12 Lower adult socioeconomic position (SEP), typically captured by low levels of income, wealth, and educational attainment or low-skilled occupation, is associated with poorer functioning, 13 lower age of onset of disabilities, 14 and steeper trajectories of functional decline. 15 The average difference in disability-free life expectancy is 17 years between people living in poor and rich areas of England. 16 Prospective evidence suggests that childhood SEP, independently of adult SEP, is associated with subsequent disability and indicators of both physical and cognitive function at least up to middle age. 17,18 Childhood SEP, often captured retrospectively, is associated with function even into older age. 19–21 These findings suggest a wide temporal window within which socioeconomic factors might influence physical and cognitive function in later life, operating through a range of potential mediating biological and social pathways. 22 They have important implications for public health interventions that target the factors across life that underlie social gradients in health. However, data to explore the relationship of prospectively assessed SEP from across life with a range of healthy aging indicators in older age through multiple mediating pathways have rarely been available. We examined the independent influence of SEP in childhood and adulthood on a range of markers of physical and cognitive performance, and an overall composite measure of these, in Britain’s oldest birth cohort study, now reaching retirement age. Although social function and psychological function are important components of healthy aging, we elected to focus on objectively assessed performance. We hypothesized that inequalities in physical and cognitive performance would be observed independently for childhood and adult SEP. A secondary aim was to assess the contribution of selected potential mediating factors to these inequalities.
