O2-2.4 Using cohorts to study lifecourse epidemiology: the MRC Lifecourse Epidemiology Unit

The MRC Lifecourse Epidemiology Unit maintains a large number of internationally unique cohort resources permitting evaluation of the developmental origins of chronic disease. Some of these comprise population-based samples of adults in whom detailed phenotyping has been undertaken; DNA has been stored; and birth/infant records have been retrieved (eg, include the Hertfordshire Cohort Study, the Helsinki Cohort Study, and the Delhi Cohort Study). Others comprise more contemporary mother-offspring studies (eg, the Southampton Women's Survey and the Pune Maternal Nutrition Study). The purpose of the Unit's research is to elucidate important, preventable causes of common chronic disorders and their complications. In particular, these cohorts permit study of the interplay of causes acting at different stages of the lifecourse, from before conception through to old age. Through an understanding of the causes of these disorders and evaluation of interventions at appropriate stages in the lifecourse, we aim to provide robust and timely evidence which informs policies to improve population and individual health. A good example is provided by research into osteoporosis and age-related fractures. The Hertfordshire Cohort Study has established that birthweight and weight in infancy are important determinants of adult bone mass, microstructure, geometry and strength. These influence the later risk of fracture. Mother-offspring cohorts have demonstrated the key role played by maternal vitamin D insufficiency during pregnancy, in the intrauterine skeletal development of the offspring. These have led to formulation of intervention studies such as a randomised controlled trial of vitamin D supplementation during pregnancy.