Initial treatment regimen and risk of hospitalization in patients with chronic obstructive pulmonary disease.

Study Objectives: Compare hospitalization risk of various initial treatment regimens for COPD.

Design: Retrospective observational cohort design.

Setting: Patients enrolled in 24 different managed care plans across the United States during 1997-2000.

Patients: Aged at least 45 years with a primary diagnosis of COPD identified. Initiation date was the date the first inhaler was dispensed. Patients were required to have filled this prescription within 60 days of the first documented COPD diagnosis in the database.

Interventions: Five therapy cohorts were identified 1) ipratropium alone or in combination with albuterol (IPR), 2) long-acting beta agonists (LABA), 3) inhaled corticosteroid (ICS), 4) ICS+IPR and 5) ICS+LABA.

Measurements: Subjects were observed for 12 months or until a COPD-related hospitalization was observed, whichever came first. A sensitivity analysis was conducted by varying the observation period from >60, >90 and >180 days to determine if this would impact the results.

Results: 3616 patients were identified, 1754 (49%) on IPR alone, 1032 (29%) on ICS alone, 357 (10%) on ICS+IPR, 266 (7%) on LABA alone and 207 (6%) on ICS+LABA. Compared with IPR alone, patients in the ICS alone and ICS plus LABA groups had a 36% and 47% reductions in the risk of a COPD hospitalization, (HR: 0.643; 95% CI 0.512, 0.808 and HR: 0.533; 95% CI 0.328, 0.865) respectively.

Conclusions: The results of this analysis suggest that initial treatment with an ICS alone or in combination with a LABA , compared to IPR alone, was associated with a significant decrease in the risk of COPD hospitalization 12 months following the start of therapy independent of concomitant asthma diagnosis. Similar outcomes were observed when the observation period was varied from >60, >90 and >180 days.