Lung function in young adults born small for gestational age at term

Abstract

Moderate to extreme prematurity is associated with lower lung function in adults1 while evidence is poorer and controversial for late prematurity.2 Likewise, the potential longterm impact on adult lung function of being born small for gestational age (SGA) at term is not well established since most previous studies in this field have been done in groups with participants enrolled by birthweight and not by SGA per se. This may be important because not all infants born SGA have experienced intrauterine growth restriction (IUGR) and the other way round, early IUGR does not necessarily bring fetal growth down below the 10th percentile (the definition of SGA). We recently showed that young adults born SGA at term had markedly reduced exercise capacity, mostly of cardiovascular origin.3 In particular, they showed lower maximal workload, peak oxygen consumption and oxygen pulse, as well as higher minute ventilation/carbon dioxide production equivalent at the anaerobic threshold, than age-matched controls. Here, we extend and complement these previously published observations with the analysis of pulmonary physiology (spirometry and carbon monoxide diffusing capacity [DLCO]) and the measurement of circulatory markers of abnormal lung development, including surfactant protein A and D (SP-A and SP-D) and club cell protein 16 (CC16).