OBJECTIVES: A considerable body of literature exists on chronic obstructive pulmonary disease (COPD), which consists of the disease processes of emphysema and chronic bronchitis. The aim of this systematic literature review (SLR) was to understand the existing evidence on the clinical and economic burden specific to emphysema.

METHODS: The SLR was conducted in accordance with PRISMA guidelines using Medline, EMBASE, EconLIT, and the Cochrane Database of Systematic Reviews. English-language studies and conference abstracts published between January 2008 and November 2018 and conducted within the United States were retained for review. Study information regarding emphysema-related risk factors, current treatments, disease progression, and economic burden were extracted and summarized.

RESULTS: Of the 1,275 abstracts reviewed, 334 studies were retained for full-text review. Data were extracted from 84 studies assessing risk factors (n=35 studies), treatments (n=39), disease progression (n=7), and economic burden (n=6; not mutually exclusive). Emphysema risk factors included clinical predictors (n=15), like genetic variants and biomarkers; environmental predictors (n=11), like exposure to dust, fumes, gas, and heavy metals; and smoking (n=7). Few studies reported demographic predictors (n=3). Emphysema treatment studies were primarily clinical trials investigating the impact of endobronchial valve therapy (n=15), lung volume reduction surgery (n=9), or pharmacological treatments (n=5), assessed on pulmonary function and/or health-related quality of life (HRQoL). Progression measures included longitudinal changes in lung density (n=2), pulmonary function (n=1), and HRQoL (n=1); no studies specified progression phenotypes. None of the 6 economic burden studies assessed healthcare resource use or costs in the general emphysema population; rather, the study populations were broader COPD patients (n=3), emphysema patients receiving pulmonary rehabilitation or augmentation therapy (n=2), or cancer survivors with emphysema (n=1).

CONCLUSIONS: The literature identified in this SLR primarily reported clinical measures. With limited literature describing resource use and economic burden in emphysema, future studies are needed to fill the evidence gap.