• chronic obstructive pulmonary disease
• GOLD staging
• prevalence

As a junior doctor I once worked in a hospital where the leading consultant in medicine refused to accept the diagnosis of asthma in patients older than 40 years. To him, airflow obstruction was “asthma” in the young and “chronic bronchitis” in the elderly. While it soon became apparent that asthma does occur after the age of 40, the likelihood of significant airflow limitation occurring in young adults who have never had asthma has always seemed small to me. In this issue of Thorax De Marco et al describe the prevalence of chronic obstructive pulmonary disease (COPD) in young adults taking part in the European Community Respiratory Health Survey (ECRHS).¹ They found COPD to be a considerable issue; in total, 3.6% had COPD stage I+ according to the NHLBI/WHO Global Initiative for Chronic Obstructive Lung Disease (GOLD)² and 11.8% had chronic respiratory symptoms without airflow limitation—that is, COPD GOLD stage 0.

The study raises several questions relating to methodology, findings, and interpretation. Diagnosis and staging of COPD was done according to the GOLD guidelines² using an FEV_{1 …}