Late-breaking abstract: Burden and risk factors of chronic bronchitis - results from the Burden of Obstructive Lung Disease (BOLD) Study

Introduction The BOLD Study is an international study aimed to describe prevalence and burden of COPD across different parts of the world. Methods Representative population-based samples of adults aged 40+ have been randomly selected in participating sites. Participants underwent questionnaire and pre- and post –bronchodilator spirometry. Chronic bronchitis (CB) was defined as chronic cough and phlegm on most days for ≥3 months each year for ≥2 years. Results 16,201 subjects from 23 sites were analyzed. CB was reported by 2.9% (95%CI: 2.3-3.4); 2.0% (95%CI: 1.6 – 2.4) in those without COPD and 11.5% (95% CI: 7.3-15.7) in those with COPD. CB prevalence varied across study sites (fig. 1). ![Figure][1] In the multivariate analyses the presence of CB was related with increased prevalence of respiratory symptoms, dyspnoea, breathing problems interfering with daily activities and reduced quality of life. Smoking, family history of chronic lung disease, and childhood lung disease were related with increased CB risk (fig. 2). ![Figure][1] [1]: pending:yes