The Effect of Physiotherapy on Interleukin-8 Levels in Patients with Chronic Obstructive Pulmonary Disease

Introduction: Interleukin-8 (IL-8), a chemokine formed by macrophages and epithelial cells and a potent chemoattractant for neutrophils, plays the principal role in the activation of neutrophils and eosinophils in the airways of patients with chronic obstructive pulmonary disease (COPD) and may be used as a marker of inflammation. The inflammation in the course of COPD may be characterised by an increased neutrophil count in the sputum and elevated IL-8 levels. The aim of the study was to assess the effect of physiotherapy on IL-8 levels in induced sputum in patients with COPD. Material and methods: The study included 44 patients (21 men and 23 women, mean age 56.47 ± 9.52) managed at the Ministry of Internal Affairs and Administration Specialist Hospital in Głuchołazy, Poland, and undergoing rehabilitation at the Therapeutic Rehabilitation Facility, with the diagnosis of COPD (FEV₁/VC < 65%), receiving stable drug treatment during physiotherapy. Before physiotherapy all the patients underwent treadmill exercise testing according to the Bruce protocol and had their dyspnoea assessed on the 20-point Borg scale as part of qualification for physiotherapy. All the patients participated a multidirectional three-week respiratory physiotherapy programme based on aerobic training performed on a cycloergometer. The training loads were selected on an individual basis depending on exercise tolerance. The standard physiotherapy programme also included respiratory muscle exercises with a particular emphasis on the abdominal muscles and the diaphragm, saline inhalations, postural drainage and percussion, relaxation and walks. Results: IL-8 levels were significantly lower after completion of the three-week physiotherapy. IL-8 levels in the sputum decreased from 18.91 ± 25.2 to 9.69 ± 14.06 ng/ml (p = 0.0215). The highest reduction of IL-8 levels was observed in patients with the highest baseline values. Conclusions: The decrease of IL-8 levels in induced sputum following comprehensive physiotherapy in patients with COPD suggests suppression of neutrophil activity, which may be one of the reasons for the improved clinical condition of the patients.