Compare asthma-related ED/hospitalizations, albuterol use (SABA) and direct asthma costs among patients prescribed fluticasone propionate (FP)/salmeterol (SL) from a single inhaler (FS) or from separate inhalers (FP + SL) as initial therapy.

Retrospective observational study using data from four large managed care plans from 2000-2002. Subjects were >15 years of age with a diagnosis of asthma (ICD-9-CM=493.xx), at least one claim for FS or FP + SL and followed for 12 months after the initial prescription for FS or FP + SL. Patients with concomitant diagnosis of COPD or cystic fibrosis were excluded. Each subject had a 12-month pre-index period with no claims for any inhaled corticosteroid, salmeterol or leukotriene receptor antagonist. Multivariate generalized linear modeling and logistic regression was used to determine the influence of these therapies on post-index asthma related costs, SABA use and ED/hospitalizations. Outcomes were adjusted for age, gender, heath-plan, co-morbidities, pre-index asthma related medications, ED/hospitalization and costs.

1422 persons were identified, 1101 new FS user and 321 new FP + SL users. FS patients were associated with a 71% lower risk of an asthma related ED/hospitalization (95% CI 48%, 84%), 50% less SABA use (p<0.01), and 11% lower direct asthma related costs (p<0.03) compared to new FP + SL patients

The results of this analysis suggest that initiation FS, compared to initial treatment with FP + SL, was associated with a reduced risk for an asthma related ED/hospitalization, lower SABA utilization and lower direct asthma health care costs.