Chronic Obstructive Pulmonary Disease (COPD)-Related Healthcare Utilization and Costs After Discharge From a Hospitalization or Emergency Department Visit on a Regimen of Fluticasone Propionate-Salmeterol Combination Versus Other Maintenance Therapies

The number of participants (par.) with a COPD-related hospitalization/ ER visit was computed during follow-up (FU) and was standardized by dividing by the total days of FU in each cohort since par. had different lengths of FU. The number of par. per 100 person-years was computed as: numerator = total number of par. with a COPD-related hospitalization/ER visit; denominator = sum of the time of FU in years across all par./100. The index date is defined as the date of discharge from a hospitalization/ER visit for COPD that had a maintenance medication dispensed within 60 days post-discharge.

The number of participants having a COPD-related event was computed during the follow-up and was standardized by dividing by the total days of follow-up in each cohort since patients had different lengths of follow-up. Four types of COPD events were defined: COPD-related hospitalization, emergency room (ER) visit, physician visit with a prescription (Rx) for oral corticosteroid or antibiotic within 3 days of the visit, or combined occurrence of any of the aforementioned three types.

Cost categories included medical, pharmacy, and total calculated as the sum of medical and pharmacy. Costs were computed during a variable follow-up period and were standardized on a per-month basis. COPD-related medical costs were computed using claims with a primary diagnosis of COPD, and COPD-related pharmacy costs were computed using the paid amounts of pharmacy claims for prescription medication used for COPD.