Rationale: While some studies suggest that poor foetal growth rate, as indicated by lower birth weight, is associated with poor respiratory function in childhood, findings among adults remain inconsistent.
Objective: To determine the association between early growth and adult respiratory function
Methods: Longitudinal birth cohort study of 5390 men and women born full term and prospectively followed from the foetal period to adulthood
Measurements: Weight at birth and infancy, and forced expiratory volume in one second (FEV1) and forced vital capacity (FVC) as assessed by standard spirometry at age 31 years.
Main results: Adult FEV1 and FVC increased linearly with higher birth weight in both men and women with no apparent threshold. After adjustment for a wide range of potential confounders operating through the lifecourse, every 500 g higher birth weight was associated with higher FEV1 by 59.8 [95% confidence interval (CI) 37.5 to 82.2] ml in men and 48.7 (95% CI 30.9 to 66.6) ml in women, and FVC of 62.6 (95% CI 36.6 to 82.5) ml in men and 41.6 (95% CI 21.0 to 62.1) ml in women. Weight gain in infancy was also positively associated with adult lung function. The magnitude of effect of lower birth weight on adult lung function was similar to or greater than that of being a smoker, leading a sedentary lifestyle or being overweight in adulthood.
Conclusion: Reduced growth in the foetal period and infancy may impair lung growth and development, the effect of which could persist into adulthood.
- Birth weight
- Postnatal growth
- Respiratory function tests