Obese asthma phenotypes display distinct plasma biomarker profiles

Background: Obese asthma is a complex phenotype and further characterization of the pathophysiology is needed. This study aimed to explore inflammation-related plasma biomarkers in lean and overweight/obese asthmatics.

Methods: We elucidated levels of inflammation-related plasma proteins in obese asthma phenotypes in the population-based cohort BAMSE (Swedish: Children, Allergy, Milieu, Stockholm, Epidemiology) using data from 2069 24-26-year-olds. Subjects were divided into lean asthma (n = 166), lean controls (n = 1440), overweight/obese asthma (n = 73) and overweight/obese controls (n = 390). Protein levels (n = 92) were analysed using the Olink Proseek Multiplex Inflammation panel.

Results: Of the 92 included proteins, 41 were associated with lean and/or overweight/obese asthma. The majority of proteins associated with overweight/obese asthma also associated with overweight/obesity among non-asthmatics. Beta-nerve growth factor (BetaNGF), interleukin 10 (IL-10), and matrix metalloproteinase 10 (MMP10) were associated only with lean asthma while C-C motif chemokine 20 (CCL20), fibroblast growth factor 19 (FGF19), interleukin 5 (IL-5), leukemia inhibitory factor (LIF), tumor necrosis factor ligand superfamily member 9 (TNFRSF9), and urokinase-type plasminogen activator (uPA) were associated only with overweight/obese asthma. Overweight/obesity modified the association between asthma and 3 of the proteins: fibroblast growth factor 21 (FGF21), interleukin 4 (IL-4), and urokinase-type plasminogen activator (uPA). In the overweight/obese group, interleukin-6 (IL-6) was associated with non-allergic asthma but not allergic asthma.

Conclusion: These data indicate distinct plasma protein phenotypes in lean and overweight/obese asthmatics which, in turn, can impact upon therapeutic approaches.