Systematic Review and Quality Appraisal of Cost-Effectiveness Analyses of Pharmacologic Maintenance Treatment for Chronic Obstructive Pulmonary Disease:Methodological Considerations and Recommendations

Worldwide, chronic obstructive pulmonary disease (COPD) is a highly prevalent chronic lung disease with considerable clinical and socioeconomic impact. Pharmacologic maintenance drugs (such as bronchodilators and inhaled corticosteroids) play an important role in the treatment of COPD. The cost effectiveness of these treatments has been frequently assessed, but studies to date have largely neglected the impact of treatment sequence and the exact stage of disease in which the drugs are used in real life.We aimed to systematically review recently published articles that reported the cost effectiveness of COPD maintenance treatments, with a focus on key findings, quality and methodological issues.We performed a systematic literature search in Embase, PubMed, the UK NHS Economic Evaluation Database (NHS-EED) and EURONHEED (European Network of Health Economics Evaluation Databases) and included all relevant articles published between 2011 and 2015 in either Dutch, English or German. Main study characteristics, methods and outcomes were extracted and critically assessed. The Quality of Health Economic Studies (QHES) instrument was used as basis for quality assessment, but additional items were also addressed.The search identified 18 recent pharmacoeconomic analyses of COPD maintenance treatments. Papers reported the cost effectiveness of long-acting muscarinic antagonist (LAMA) monotherapy (n = 6), phosphodiesterase (PDE)-4 inhibitors (n = 4), long-acting beta agonist/inhaled corticosteroid (LABA/ICS) combinations (n = 4), LABA monotherapy (n = 2) and LABA/LAMA combinations (n = 2). All but two studies were funded by the manufacturer, and all studies indicated favourable cost effectiveness; however, the number of quality-adjusted life-years (QALYs) gained was small. Less than half of the studies reported a COPD-specific outcome in addition to a generic outcome (mostly QALYs). Exacerbation and mortality rates were found to be the main drivers of cost effectiveness. According to the QHES, the quality of the studies was generally sufficient, but additional assessment revealed that most studies poorly represented the cost effectiveness of real-life medication use.The majority of studies showed that pharmacologic COPD maintenance treatment is cost effective, but most studies poorly reflected real-life drug use. Consistent and COPD-specific methodology is recommended.