Background. A community-based prevalence survey performed in two suburbs in Cape Town, South Africa (SA), in 2005, using the international Burden of Obstructive Lung Disease (BOLD) method, confirmed a prevalence of chronic airflow obstruction (CAO) in 23.1% of adults aged >40 years. Objectives. To study the clinical course and prognosis over 5 years of patients with CAO identified in the 2005 survey. Methods. P...