Relationship of perfluoroalkyl chemicals with chronic obstructive pulmonary disease: A cross-sectional study.

Perfluoroalkyl chemicals are one of the most stable substances in industry and have become ubiquitous contaminants owing to their persistence in the environment. This study enrolled 1,953 participants aged ≥40 years old using data from the National Health and Nutrition Examination Survey (NHANES). We selected four perfluoroalkyl chemicals with a detection frequency of more than 80%, including perfluorohexane sulfonic acid (PFHxS), perfluorononanoic acid (PFNA), perfluorooctanoic acid (PFOA), and perfluorooctane sulfonic acid (PFOS). Multivariate logistic regression was performed to determine the relationship of serum perfluoroalkyl chemicals with COPD and airflow limitation. We evaluated the interaction between perfluoroalkyl chemicals and lung function using multivariate linear regression analyses. Our results showed that the prevalence of COPD was not significantly related to serum PFHxS, PFNA, PFOA, and PFOS. Airflow limitation was positively linked with serum PFHxS, PFOA, and PFOS. However, these significant differences were not robust after adjustment of all confounders of interest. Serum PFHxS, PFOA, and PFOS were all positively related to the forced expiratory volume in 1 second (FEV1), forced vital capacity (FVC), and peak expiratory flow (PEF). However, only PFOA remained significantly linked with the FEV1 and FVC after covariate adjustment. These results indicated that there was no significant interaction between exposure to perfluoroalkyl chemicals and the prevalence of COPD. Higher levels of serum PFOA appeared to be related to higher measures of FEV1 and FVC.