Background: Some recent studies report associations between phthalate exposure and asthma in pre-school children. We investigated if circulating levels of phthalates and bisphenol A (BPA) predicts lung function decline in an elderly population.
Methods: PIVUS is a cohort, based on a population sample of subjects, aged 70 years in Uppsala, Sweden. Circulating levels of BPA and phthalate metabolites in serum was measured at baseline by LC-MS/MS. Lung function was measured at baseline and after 5 years in 668 subjects. Change of forced expiratory volume in 1 s (FEV1) was calculated. Associations were analysed by multivariate modelling adjusting for height, smoking at 70 and 75 y, pack years of tobacco at 70 y, education level, exercise habits and gender, using ln transformed values for circulating levels, excluding 36 subjects with asthma or COPD at baseline
Results: BPA median level was 3.75 ng/mL, Monethyl hexyl phtalate (MEHP) 4.51 ng/mL, monethyl phtalate (MEP) 11.6 ng/mL, Monoisobutyl phtalate (MiBP) 13.5 ng/mL, and Monomethyl phtalate (MEHP) 1.51 ng/mL, with no gender differences. The annual decline in FEV1 was -55.6 ml/year. MEHP was associated with an additional decline in FEV1 of -6.0 ml/year (95% CI -8.6 to -3.4) (p<0.001), while MMP was associated with an additional improvement in FEV1 of 6.6 ml/year (95% CI 3.2 to 9.8) (p<0.001), The association for MEHP was significant in both men and women, while the association for MMP was significant in women, only.
Discussion: Associations between circulating levels of some phthalates metabolites and the five year decline of FEV1 were found, with MEHP as a risk factor for lung function decline.