Biomarkers of Oxidative Stress, Systemic Inflammation and Thrombosis in Adult Asthmatic Patients Treated with Inhaled Corticosteroids During Exposure to Fine Particulate Matter

<b>Background/Objectives:</b> Inhaled corticosteroids (ICS) affect oxidative stress and systemic inflammation, which might modify the risk of thrombosis in asthmatic patients exposed to particulate matter with an aerodynamic diameter smaller than 2.5 microns (PM_2.5). Therefore, we aim to know the systemic biomarkers of oxidative stress, inflammation, and coagulation in ICS-treated, well-controlled adult asthmatic patients after exposure to PM_2.5. <b>Methods:</b> This study was conducted to compare urinary biomarkers of oxidative stress, i.e., 8-hydroxydeoxyguanosine (8-OHdG), and blood biomarkers of inflammation and hypercoagulation, i.e., complete blood count (CBC), high-sensitivity C-reactive protein (hsCRP), fibrinogen, D-dimer, tumor necrosis factor-alpha (TNF-α), and interleukins (IL-6 and IL-8), between well-controlled adult asthmatic patients and healthy controls in low and high-pollution periods. <b>Results:</b> Forty-one ICS-controlled asthmatic patients and twenty controls were included. Urinary 8-OHdG, white blood cells and differential counts, platelets count, hsCRP, IL-6, and IL-8 in the asthma group were not significantly higher than controls during the same period. The D-dimer level of the asthma patients was significantly higher than the controls (<i>p</i> < 0.05). The median level of TNF-α levels during the pollution period in asthma patients was significantly higher than the non-pollution period with levels of 14.3 (9.3, 27.4) and 11.3 (7.8, 21.1) pg/mL, <i>p</i> = 0.041, respectively. <b>Conclusions:</b> During exposure to PM_2.5, serum TNF-α was increased while the other markers of oxidative stress and inflammation were not high in ICS-treated asthma. ICS might mitigate PM_2.5-induced systemic oxidative stress, inflammation, and hypercoagulation in asthma.