Economic assessment of initial maintenance therapy for chronic obstructive pulmonary disease.

OBJECTIVE: To compare the effects of initial maintenance therapy with fluticasone 250 microgram plus salmeterol 50 microgram in a single inhaler versus other inhaled medications on exacerbation risks and treatment costs among chronic obstructive pulmonary disease (COPD) patients.

STUDY DESIGN: A retrospective observational analysis was conducted by using medical/pharmacy claims from a large managed care database between January 2000 and February 2004. Patients age 40 years or older with a primary diagnosis of COPD (International Classification of Diseases, Ninth Revision, Clinical Modification code 490, 491, 492, or 496), at least 18 months of continuous eligibility, and an index prescription for fluticasone/salmeterol combination, salmeterol alone, inhaled corticosteroid alone, ipratropium/albuterol combination, or ipratropium alone (reference) were identified.

METHODS: Time to first COPD-related hospitalization or emergency department (ED) visit was estimated by using Cox proportional hazard models. All-cause and COPD-related treatment costs were estimated by using generalized linear models with a gamma distribution and log link. Multivariable regressions were used, controlling for age, sex, comorbidities, COPD subtype, preindex medications, and hospitalizations and ED visits.

RESULTS: Initial maintenance therapy with fluticasone/salmeterol combination was associated with a 31% to 56% lower risk of hospitalization or ED visit compared with ipratropium alone, adjusting for baseline characteristics and preindex resource utilization. Fluticasone/salmeterol combination therapy was related to lower medical costs, higher pharmacy costs, and almost similar total costs in all populations studied.

CONCLUSION: Fluticasone/salmeterol combination therapy was considered to be cost-effective compared with ipratropium alone because it achieved better clinical outcomes with similar or lower treatment costs.