Prevalence of COPD in 6 Urban Clusters in Argentina: The EPOC.AR Study

Abstract Introduction The prevalence of chronic obstructive pulmonary disease (COPD) has not been studied in Argentina. Objectives To determine the prevalence and relevant clinical characteristics of COPD in a representative sample. Material and methods We performed a cross-sectional study in a population of adults aged ≥40 years randomly selected by cluster sampling in 6 urban locations. Subjects answered a structured survey and performed pre- and post-bronchodilator spirometry (PBD). COPD was defined as FEV 1 /FVC ratio Results Of 4599 surveys and 3999 spirometries, 3469 were considered of adequate quality (86.8%) for our study. The prevalence of COPD was 14.5% (CI: 13.4–15.7). The distribution of COPD cases according to FEV1 (GOLD 2017) was stage 1: 38% (CI: 34–43); stage 2: 52% (CI: 47–56); stage 3: 10% (CI: 7–13); and stage 4: 1% (CI: 0–2), and according to the refined ABCD (GOLD 2017) assessment: A: 52% (CI: 47–56); B: 43% (CI: 39–48); C: 1% (CI: 0–2); D: 4% (CI: 2–6). The rate of underdiagnosis was 77.4% (CI: 73.7%–81.1%) and diagnostic error 60.7% (CI: 55.1%–66.3%). A significant association was found between COPD and age (OR 3.77 in individuals 50–59 years of age and 19.23 in those >80 years), male gender (OR 1.62; CI: 1.31–2), smoking (OR 1.95; CI: 1.49–2.54), low socioeconomic status (OR 1.33; CI: 1.02–1.73), and previous tuberculosis (OR 3.3; CI: 1.43–7.62). Conclusions We estimate that more than 2.3 million Argentineans have COPD, with high rates of underdiagnosis and diagnostic error.