LATE-BREAKING ABSTRACT: Serum 25(OH)D concentrations are associated with lung function in adolescence

Abstract

Background: Vitamin D plays a role in the development of the immune system and the lung as well as in airway remodelling. Objective: This study investigated the association between serum 25-hydroxyvitamin D [25(OH)D] concentrations and spirometric lung function parameters at the age of 15 years. Methods: In the German GINIplus and LISAplus birth cohorts, lung function testing by spirometry and blood sampling were performed during the 15-year follow-up examinations. 2607 adolescents had valid lung function measurements pre- and/or post-bronchodilation and serum 25(OH)D concentrations measured by the Elecsys vitamin D total test (Roche Diagnostics). Serum 25(OH)D concentrations were adjusted for the date of blood sampling to account for the seasonal variability. Associations between season-adjusted 25(OH)D concentrations and spirometric parameters were analysed using generalised linear regression models with adjustment for confounding factors such as sex, height, weight, time spent indoors and current asthma. Results: Serum 25(OH)D concentrations were significantly associated with forced vital capacity (FVC), forced expiratory volume in 1 second (FEV 1 ) and the ratio of FEV 1 and FVC measured before bronchodilation after adjustment for potential confounders: FEV 1 increased by 10ml (95%CI=[2;17]), FVC by 20ml (95%CI=[12;28]) and FEV 1 /FVC decreased by 0.177% (95%CI=[-0.286;-0.067]) per 10nmol/l increase in 25(OH)D concentrations. Flow rates (FEF 25 , FEF 50 , FEF 75 and FEF 25-75 ) were not associated with vitamin D. Similar associations were observed for lung function parameters measured after bronchodilation. Conclusion: Vitamin D concentrations are positively associated with volume related lung function parameters.