A prospective study of salvational intervention with ICS/LABA for reducing chronic obstructive pulmonary disease exacerbation under severe air pollution (SIRCAP) in Beijing: protocol of a multi-center randomized controlled trial

Abstract Background Chronic Obstructive Pulmonary Disease (COPD) is a major cause of morbidity and mortality all over the world. Acute exacerbation of COPD (AECOPD) not only accelerates the progression of disease, but also causes hospital administration and death events. Epidemiologic studies have shown air pollution is a high risk factor of AECOPD. However, there are rare technics or treatment strategies recommended to reduce severe air pollution related AECOPD. Methods This is a multi-center, prospective, randomized and standard treatment parallel control clinical trial. Seven hundred sixty-four stable COPD patients in group B, C and D according to GOLD 2017 will be recruited and equally divided into two parallel groups, salvational intervention (SI group) and control group (CT group). Original treatments for participants include tiotropium (18μg once q.d), budesonide/formoterol (160μg/4.5μg once or twice b.i.d) or budesonide/formoterol (160μg/4.5μg once or twice b.i.d) with tiotropium (18μg once q.d). The savational intervention for SI group is routine treatment plus budesonide/formoterol (160μg/4.5μg once b.i.d) from the first day after severe air pollution (air quality index, AQI ≥200) to the third day after AQI