Prevalence of COPD in 6 Urban Clusters in Argentina: The EPOC.AR Study. / Prevalencia de enfermedad pulmonar obstructiva crónica en 6 aglomerados urbanos de Argentina: el estudio EPOC.AR.

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 FEV1/FVC ratio < 0.7 predicted value. The total prevalence was estimated for each cluster with its 95% confidence interval (CI). RESULTS: Of 4,599 surveys and 3,999 spirometries, 3,469 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.