Chronic obstructive pulmonary disease : A global disease with important local variation

Background: Chronic obstructive pulmonary disease (COPD) is a leading cause of morbidity and mortality in both the developed and developing world. Some of the differences seen in COPD prevalence, and mortality seen at the local level may provide insights into prevention strategies. Methods: We reviewed estimates of COPD prevalence in both multinational studies (the Burden of Obstructive Lung Disease project) and US based studies (BRFSS). We also reviewed and compared estimates of COPD mortality using global data from the Burden of Disease project and state-based data from CDC Wonder. Results: COPD prevalence has been estimated in countries participating in the BOLD project in 16 countries. These estimates ranged from 5.1% in Chinese women to 22.1% in South African men. Similarly, COPD prevalence, based on self-reported physician diagnoses in US States, ranged from 4.1% in Minnesota to 10.1% in Kentucky. Age-adjusted COPD mortality rates (2004) also varies globally, ranging from 0.8/100,000 in Kuwait to 66.0/100,000 in Denmark (limited to countries with populations greater than 1 million and reliable death certificate data). In the US, COPD mortality by state in 2010 ranged from 24.8/100,000 in Hawaii to 102.6/100,000 in Oklahoma. The relation between COPD prevalence and mortality also varies greatly, indicative, perhaps, o f the variation in COPD risk factors both locally and globally. Conclusions: Estimates of COPD burden vary dramatically and are related to a number of different factors. Better understanding of these data and the factors driving them should lead to improved prevention strategies for COPD.