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.