Early life environment and the developing cardiovascular system

Background The dynamics of cardiovascular system development in childhood are still largely unknown. Despite its known sensitivity to small perturbations, it has not been fully elucidated how the cardiovascular system evolves and responds to different stimuli and how these impact the future cardiovascular status. This thesis is basically aimed at exploring the effects of several possible postnatal determinantson the developing cardiovascular system. These early life determinants perhaps immediately cause cardiovascular issues in childhood and contribute to cardiovascular risk in later life. Particular attention is given to childhood conditions that are relevant for low-to-middle income countries, including malnutrition and physical activity. We specifically also look at HIV infection as a model of childhood inflammation which may have profound effects on the developing cardiovascular system. Methods Our research questions are addressed through several studies as follows: (1) a pilot/feasibility study of a currently enrolling randomized breastfeeding optimization trial (NCT01566812 )in Indonesia to investigate determinants of breastfeeding planning in pregnant women; (2) a Prospect-European Prospective Investigation into Cancer and Nutrition (Prospect-EPIC) cohort to study the effects of famine exposure in childhood on coronary artery calcifications; (3) An ongoing Wheezing Illnesses Study in Leidsche Rijn (WHISTLER) birth cohort to study the effects of physical activity on childhood vascular characteristics; (4) A cohort of 111 HIV infected and 51 healthy children in Jakarta, Indonesia to study the effects of ART-naive and ART-exposed HIV infection on childhood cardiac status and future cardiovascular risk. Results We found that childhood physical activity, famine, and HIV infection seemed to determine future cardiovascular disease risk in adulthood. Higher physical activity level was associated with better vascular properties with thinner intima media thickness. Famine in childhood increased the risk of coronary artery calcification in later life. HIV infection in children was associated with various alterations in heart structure, function, and the conduction system in childhood. Moreover, childhood HIV may increase future cardiovascular disease risk as we found a significantly thicker intima media among treatment naive HIV infected children. Given that breastfeeding is beneficial for childhood vascular properties, we sought the determinants of breastfeeding plan in pregnant women and found that the likelihood of giving exclusive breast feeding was related to mothers being well informed, regardless their social and educational background. Conclusions Postnatal influences, including childhood nutrition, physical activity, and morbidities appear to shape cardiovascular development, which not only affects childhood cardiovascular status but also may determine future cardiovascular risk in adulthood.