Birth Weight and Lung Function in Adulthood: A Systematic Review and Meta-analysis

Area of Science:

• Pulmonary Medicine
• Epidemiology
• Developmental Biology

Background:

• Birth weight is a potential determinant of adult lung function.
• The differential impact of birth weight on restrictive (FVC) versus obstructive (FEV1/FVC) lung function patterns remains unclear.

Purpose of the Study:

• To systematically review and meta-analyze evidence on the association between birth weight, weight at 1 year, and weight gain in the first year of life with adult FVC and FEV1/FVC.
• To assess the strength and consistency of these associations.

Main Methods:

• Systematic literature review of MEDLINE, EMBASE, and Web of Science up to January 2015.
• Inverse-variance weighted random-effects meta-analysis to combine data.
• Subgroup and sensitivity analyses conducted based on age, country wealth, ethnicity, sex, and smoking status.
• Risk of bias and reporting bias were evaluated.

Main Results:

• Eighteen articles were included, with 13 contributing to meta-analyses.
• Strong evidence shows a positive association between birth weight and adult FVC (59.4 ml/kg increase).
• Evidence for an association between birth weight and adult FEV1/FVC was weaker and inconsistent.
• Limited data were available for weight at 1 year and weight gain in the first year.

Conclusions:

• Birth weight is strongly and consistently associated with adult FVC, a marker of restrictive lung disease.
• The association between birth weight and adult airflow obstruction (FEV1/FVC) is less robust.
• Further research may be needed to clarify the role of early-life weight gain on lung function patterns.