Parental education and lung function of children in the PATY study

Studies of the relationships between low socio-economic status and impaired lung function were conducted mainly in Western European countries and North America. East–West differences remain unexplored. Associations between parental education and lung function were explored using data on 24,010 school-children from eight cross-sectional studies conducted in North America, Western and Eastern Europe. Parental education was defined as low and high using country-specific classifications. Country-specific estimates of effects of low parental education on volume and flow parameters were obtained using linear and logistic regression, controlling for early life and other individual risk factors. Meta-regressions were used for assessment of heterogeneity between country-specific estimates. The association between low parental education and lung function was not consistent across the countries, but showed a more pronounced inverse gradient in the Western countries. The most consistent decrease associated with low parental education was found for peak expiratory flow (PEF), ranging from −2.80 to −1.14%, with statistically significant associations in five out of eight countries. The mean odds ratio for low PEF (<75% of predicted) was 1.34 (95% CI 1.06–1.70) after all adjustments. Although social gradients were attenuated after adjusting for known risk factors, these risk factors could not completely explain the social gradient in lung function.