Peak weight velocity in infancy is negatively associated with lung function in adolescence. Results from the GINIplus study.
Background: Weight gain during infancy increases the risk of asthma in childhood which might be related to lower lung function. This study aimed to investigate the association between dynamics of growth (peak weight velocity) during the first two years of life and spirometric lung function indices measured at 15 years of age.
Methods: Data from 1842 children who participated in the GINIplus (German Infant Nutritional Intervention plus environmental and genetic influences on allergy development) birth cohort and who underwent spirometry at 15 years of age were analysed. Peak weight velocity (PWV) was calculated from weight measurements obtained between birth and two years of age. Generalised additive models were fitted after adjustment for potential confounding factors including birth weight, height and age at lung function testing. Results are presented per interquartile range increase (IQR) in PWV.
Results: Peak weight velocity was negatively associated with prebronchodilator flow rates, e.g. FEF50 (forced expiratory flow at 50% of forced vital capacity) decreased by 129 ml/s (β: -0.129; 95% confidence interval: [-0.211; -0.046]), FEF75 by 71 ml/s (β: -0.071; [-0.130; -0.012]) and FEF25 – 75 by 103 ml/s (β: -0.103; [-0.176; -0.030]). Forced expiratory volume in 1 s (FEV1) and forced vital capacity (FVC) were not associated with PWV (β: -0.013; [-0.047; 0.022] and β: 0.013; [-0.025; 0.051], respectively). However, FEV1/FVC showed a statistically significant association with early weight gain (β: -0.691; [-1.207; -0.174]). All these associations were independent of birth weight. Similar results were found for lung function indices measured after bronchodilation.
Conclusion: Weight gain early in life is negatively associated with lung function parameters, primarily representing flow indices, in adolescence suggesting structural and not functional changes in peripheral lungs.