LAUSR

Chronic obstructive pulmonary disease (COPD) is one of the leading causes of death around the world [1]. Chronic airflow obstruction (CAO), measured by spirometry, is the most commonly used objective characteristic of COPD [2]. Epidemiological research has provided researchers and clinicians with critical information about the burden of COPD and its risk factors; [3–9]; however, very few studies have investigated the productivity-related burden of COPD [10–12]. The Burden of Obstructive Lung Disease (BOLD) study is one of the best designed epidemiological studies investigating prevalence and risk factors for COPD, and has been vital in improving our understanding of COPD around the world [3, 13]. In this issue of the European Respiratory Journal, Grønseth et al. [14] estimate the association between CAO and unemployment at 26 BOLD sites. The study demonstrates that there is greater unemployment in participants with CAO, which was partially confounded by socioeconomic factors. Importantly, the study reports no association in low and middle income countries (LMIC), which emphasises the diversity of risk factors and burden of COPD in different parts of the world. The causal association between chronic airflow obstruction and unemployment is complex and requires further study http://ow.ly/INtD30eqgJJ