Impact of tobacco smoking on the clinical and functional indicators and markers of systemic inflammation in patients with severe asthma

Abstract

Aim. To study cytokine status and to reveal a possible relationship of clinical and functional indicators and systemic inflammation in patients with severe asthma to tobacco smoking. Subjects and methods. Examinations were made in 139 patients with severe asthma during its exacerbation and without the latter after 12 months. Groups 1 and 2 included 98 nonsmoking and 41 smoking patients with severe asthma, respectively. A control group consisted of 40 apparently healthy volunteers. External respiratory function, plasma TNF-α, IFN-γ, IL-2, IL-4, IL-6, IL-8, IL-10, C-reactive protein, and neutrophil elastase levels, and integral cytokine index were studied. Results. Systemic inflammation that was more marked on a disease exacerbation and mediated by elevated TNF-α, IL-2, and C-reactive protein levels was detected in severe asthma in both groups. The smoking patient group showed a statistically significant increase in IL-8 and neutrophil elastase levels, which may be indirectly indicative of the active participation of neutrophils in the development of chronic persistent inflammation. Conclusion. Tobacco smoking is a clinically significant risk factor that aggravates both the course of asthma and the magnitude of inflammation during a disease exacerbation.

Keywords

• bronchial asthma
• cytokines
• smoking
• systemic inflammation