Background: Low birth weight is associated with lower values for spirometry in adults but it is unknown if birth weight influences other measures of pulmonary function. It is also unclear whether post-natal growth affects adult lung function. We assessed the associations between birth weight, post-natal growth and adult lung function in an unselected birth cohort of 1037 children.
Methods: Birth weight, weight gain between birth and age 3 years, and lung function at age 32 years were measured. Analyses adjusted for adult height and sex and further adjusted for multiple other potential confounding factors.
Results: Birth weight was positively correlated with spirometric (FEV1 and FVC) and plethysmographic (TLC and FRC) lung function and with lung diffusing capacity. These associations persisted after adjustment for confounding factors including adult weight, exposure to cigarette smoke in utero and during childhood, personal smoking, socio-economic status, asthma, and gestational age. Weight gain between birth and age 3 was also positively associated with lung diffusing capacity, and was associated with higher values of lung volumes in men after adjustment for covariates. Neither birth weight nor post-natal weight gain were associated with airflow obstruction.
Conclusions: Low birth weight and lower weight gain in early childhood are associated with modest reductions in adult lung function across a broad range of measures of lung volumes and with lower diffusing capacity. These findings are independent of a number of potential confounding factors and support the hypothesis that foetal and infant growth is a determinant of adult lung function.