Chronic obstructive pulmonary disease exacerbations : cost, risk factors and impact of long-acting muscarinic antagonists

Abstract

Health care resource utilisation (HCRU) data for chronic obstructive pulmonary disease (COPD) exacerbation-related hospitalisations can be used to drive the introduction of long-acting muscarinic antagonists (LAMAs) in the Maltese National Health Service (NHS). An understanding of the predictors for COPD exacerbations leading to hospitalisation may assist in developing guidelines for LAMA use, which prioritise patients who would benefit most from this therapy. A data collection proforma was designed and validated. All the hospital admissions during February-April 2017 were screened and a total of 148 COPD exacerbation-related admissions were identified. The cost estimates for these admissions were computed using an activity-based costing (ABC) approach. A case-control study was used to identify the predictors for COPD exacerbation-related hospitalisation. A total of 81 cases were recruited by convenience sampling from the identified admissions. Another 81 patients were recruited from respiratory outpatients as control subjects, during the same time frame. Control patients had to be clinically stable without a COPD exacerbation-related hospitalisation during the previous year. The data collection proforma was completed for recruited cases and control patients. Data was gathered from patients’ medical records and via patient selfreport. Pre-validated tools (COPD assessment test (CAT), EQ-5D-3L, inhaler adherence scale, inhaler technique scores) were completed through a semi-structured interview. The total estimated hospitalisation cost amounted to €225,000. Parsimonious logistic regression identified six significant predictors for hospitalisation. CAT scores above 18.9 (OR 1.193; 95% CI 1.096-1.299), a history of at least 2 past COPD exacerbation related hospitalisations (OR 1.702; 95% CI 1.238-2.339), and at least 3 concomitant comorbidities (OR 1.593; 95% CI 1.025-2.474), were positively associated with the occurrence of a hospitalisation. Lack of inhaled long-acting beta agonists (LABA) therapy (OR 6.494; 95% CI 0.041-0.587), emergency nebuliser use in the last 3-months (OR 4.537; 95% CI 1.209-17.039) and intravenous (IV) antibiotic use in the last 3 months (OR 8.545; 95% CI 1.093-66.827), were also positively associated with the occurrence of a hospitalisation. The identified predictors for COPD exacerbation-related hospitalisation may be used to prioritise patient access to LAMA therapy.