Background: According to evidence-based guidelines, the combination of inhaled corticosteroids and inhaled long-acting beta(2)-agonists in a single inhaler is recommended for patients with chronic obstructive pulmonary disease (COPD) who are experiencing exacerbations. The relative effectiveness of combination products such as budesonide/formoterol (BUD/FM) and fluticasone propionate/salmeterol (FP/SM) has not been well documented. Objective: This study was conducted to investigate the different outcomes associated with the use of either BUD/FM or FP/SM in a single inhaler in patients with COPD. Outcomes included rates of exacerbations, emergency department (ED) visits and hospitalizations for COPD, medication utilization, and treatment adherence. Methods: A 1-year, population-based, matched cohort study was conducted using administrative health care data bases from the Canadian province of Quebec. Patients treated with BUD/FM were matched (1:1) to patients treated with FP/SM based on the following criteria: age group, sex, calendar year of treatment initiation, the number of COPD exacerbations in the year before treatment initiation, and use of inhaled short-acting beta(2)-agonists (SABAs) and ipratropium bromide in the 3 months before treatment initiation. COPD exacerbations were defined as a claim for a short-course (<= 14 days) prescription of oral corticosteroids, or an ED visit or a hospitalization for COPD. Events occurring within 15 days were counted as a single exacerbation. Between-group comparisons of the number of exacerbations, ED visits, and hospitalizations for COPD, as well as claims for oral corticosteroids, were performed using Poisson regression models. Between-group comparisons of the mean number of doses of SABAs and ipratropium bromide per day were performed using linear regression models. Treatment adherence was also assessed. Results: Of the 2262 patients in the matched cohort, 78.1% were aged >= 65 years and 52.1% were men. COPD exacerbations, claims for oral corticosteroids, use of SABAs, and patient adherence to treatment did not differ significantly between the BUD/FM and FP/SM groups. However, the BUD/FM group was significantly less likely to have an ED visit (adjusted relative risk [RR] = 0.75; 95% CI, 0.58 to 0.97) or hospitalization (adjusted RR = 0.61; 95% CI, 0.47 to 0.81) for COPD and had fewer claims for prescriptions for tiotropium (adjusted RR = 0.71; 95% CI, 0.57 to 0.89). The BUD/FM group also used fewer doses of ipratroprium bromide than the FP/SM group (adjusted mean difference, 0.2 dose; 95% CI, 0.3 to 0.1). Conclusions: These COPD patients treated with BUD/FM were less likely to have ED visits and hospitalizations for COPD and used fewer doses of anticholinergic medication than patients treated with FP/SM in the year after treatment initiation. However, due to the observational nature of the study design, we cannot conclude with certainty that the medication was the only factor responsible for the observed differences. (Clin Ther. 2010;32:1320-1328) (C) 2010 Excerpta Medica Inc.
