Systemic inflammatory biomarkers in relation to lung function and exercise-induced bronchoconstriction in adolescents

Abstract

Introduction: The forced oscillation technique (FOT) complements spirometry in assessing lung function, with higher sensitivity to small airway dysfunction. Systemic inflammation is thought to influence lung development and exercise-induced bronchoconstriction (EIB), but its relationship to circulating inflammatory proteins in adolescents is unclear. Objective: To investigate associations between systemic inflammatory biomarkers and baseline lung function and post-exercise airway responses in adolescents. Methods: In 143 adolescents (13–15 years) from a population-based cohort, baseline spirometry, FOT, and baseline blood samples were obtained. Participants completed an exercise challenge to assess EIB via changes in forced expiratory volume in 1 s (FEV1), resistance at 5 Hz (R5), and reactance at 5 Hz (X5). Plasma protein levels were measured using the proximity extension assay technique (Olink Target Inflammation and Immune Response panels). Associations with lung function (FEV1% predicted, R5, and X5 z-scores) and post-exercise responses (∆FEV1, ∆R5, ∆X5) were analyzed using linear regression with false discovery rate correction. Interaction with atopy was also examined. Results: Higher plasma levels of C-C motif chemokine 19 (CCL19) were significantly associated with lower FEV1% predicted and lower X5 z-scores at baseline, indicating reduced lung function and impaired small airway function. No proteins were associated with post-exercise airway responses after correction. Five proteins showed significant interactions with atopy in relation to EIB. Conclusion: Elevated CCL19 may reflect systemic inflammatory processes contributing to impaired lung function in early adolescence. The observed atopy-related interactions suggest the need to consider atopy in studies of systemic inflammation and airway physiology.