Background: Chronic obstructive pulmonary disease (COPD) causes significant morbidity and mortality. COPD is defined as a modifiable and treatable disease, but studies have shown that smoking cessation is the only intervention that reduces the rapid decline in forced expiratory volume in one second (FEV1). Multiple guidelines consider COPD an inflammatory disease and recommend corticosteroids as treatment. Inhaled corticosteroids are used at all stages of COPD. However, guidelines recommend that inhaled corticosteroids be reserved for those with an FEV1 less than 50 percent of predicted volume because these therapies have been shown to improve symptoms, reduce exacerbations, and improve quality of life in patients with frequent exacerbations. The long-term impact of inhaled corticosteroids in COPD treatment has been debated. Studies have been inconsistent about whether inhaled corticosteroids can alter the natural history of COPD. Soriano and associates evaluated the effect of inhaled corticosteroids on FEV1 in patients with COPD.
The Study: Data from seven randomized controlled trials that evaluated the long-term effect of inhaled corticosteroids in patients with COPD were pooled and analyzed. All selected studies randomly assigned patients with COPD to inhaled corticosteroids or placebo while the patients were in a stable phase. COPD ranged from mild to severe, and participants were 40 years and older. Spirometry, using methods and machines that met accepted standards, was performed every six months after randomization. Only patients who had three or more spirometry measurements over time were included in the analysis. Data collected were patient age, sex, body mass index, and smoking status at the start of the trials.
Results: There were 3,911 patients who met the inclusion criteria for the study. After six months, patients who received inhaled corticosteroids had significant improvement in FEV1 compared with the placebo group. From six to 36 months, the decline in FEV1 was the same for the treatment and placebo groups. During the first six months, former smokers had a significant increase in FEV1 compared with current smokers, and female former smokers had a greater increase in FEV1 compared with male former smokers. After six months, there was no difference in the rate of FEV1 decline between men and women or between current smokers and former smokers.
Conclusion: The authors conclude that the use of inhaled corticosteroids in patients with COPD provides some benefit in FEV1 during the first six months of treatment compared with placebo; however, the effect on FEV1 decline does not seem to continue after six months. This initial benefit appears to be greater in former smokers compared with current smokers and in women compared with men.