The material covered in this Review is based on an extensive literature search and participation in expert meetings during the writing and updating of guidelines for the treatment of chronic obstructive pulmonary disease, along with many years of research in the area. We did a systematic Medline search for articles in English or with English abstracts with the keywords: “COPD” or “emphysema” or “chronic bronchitis” AND “prevalence” or “burden” or “risk factors” or “cost” or “morbidity” or
ReviewGlobal burden of COPD: risk factors, prevalence, and future trends
Section snippets
Definition
The working definition of COPD, as noted in the 2006 update of the Global Initiative for Obstructive Lung Disease (GOLD) guidelines, is that COPD is “a preventable and treatable disease with some significant extrapulmonary effects that may contribute to the severity in individual patients. Its pulmonary component is characterised by airflow limitation that is not fully reversible. The airflow limitation is usually progressive and associated with an abnormal inflammatory response of the lungs to
Disease classification
COPD can be classified with respect to both phenotype and disease severity. It is a heterogeneous disease process that varies greatly from person to person with respect to lung pathology, natural history of disease, and comorbidity. A result of this heterogeneity is that different researchers have championed alternative hypotheses about COPD development over the past four decades: the British hypothesis stated that the presence of cough and sputum was the key factor in COPD,22 and the Dutch
Risk factors
Risk for COPD is related to an interaction between genetic factors and many different environmental exposures, which could also be affected by comorbid disease. Risk factors for the disease are described below.
Prevalence estimates
Two reviews have been published58, 59 in which the prevalence of COPD was noted to be highly variable, probably because of differences in methods for establishment of disease prevalence. Figure 4 shows the findings from the 12 sites of the BOLD study26 and the five sites in the Latin American Project for the Investigation of Obstructive Lung Disease (PLATINO) study.60 These estimates, even with identical methodologies, show a large amount of variability. For example, in the BOLD study,26 GOLD
Morbidity and mortality
Additional measures of the burden of COPD, such as morbidity, mortality, and costs, present challenges similar to those seen in attempting to measure disease prevalence. Table 3 shows WHO estimates of deaths and disability-adjusted life years attributable to COPD for the world's 25 most populous nations.1 This table highlights some of the difficulties with these other measures of COPD. For example, the estimated COPD death rate in Japan of 4·4/100 000 is nearly 30 times lower than that in China
Future trends
When Calverley and Walker reviewed COPD in 2003 they made some predictions about progress in disease.2 With respect to pathogenesis, they forecast that there would be greater phenotypic characterisation of COPD, identification of candidate susceptibility genes, clarification of the basis of steroid resistance, and enhanced animal models of the disease. With respect to clinical characteristics, they predicted that there would be better methods of detecting flow limitation and staging systems
Conclusion
Our knowledge of COPD has grown over the past few years. Additional questions are raised by this new knowledge, which are discussed here. One of the biggest advances in COPD is greater understanding of disease burden in different countries and cultures. Publication of data from the PLATINO60 and BOLD26 studies is vital to establish how important COPD is, particularly in view of the disease's consistent underdiagnosis at sites where it has been investigated.76, 77, 78 Other relevant components
Search strategy and selection criteria
References (82)
- et al.
Chronic obstructive pulmonary disease
Lancet
(2003) - et al.
Burden and clinical features of chronic obstructive pulmonary disease (COPD)
Lancet
(2004) - et al.
Improving the care of COPD patients: suggested action points by the COPD exacerbations taskforce for reducing the burden of exacerbations of COPD
Prim Care Respir J
(2006) - et al.
What have we learnt from large drug treatment trials in COPD?
Lancet
(2007) COPD exacerbations: defining their cause and preventions
Lancet
(2007)- et al.
Anxiety and depression in COPD patients: the roles of gender and disease severity
Respir Med
(2006) Pathophysiology of airflow limitation in chronic obstructive pulmonary disease
Lancet
(2004)- et al.
α1-antitrypsin deficiency
Lancet
(2005) COPD: overview of definitions, epidemiology, and factors influencing its development
Chest
(1998)- et al.
Global Initiative on Obstructive Lung Disease (GOLD) classification of lung disease and mortality: findings from the Atherosclerosis Risk in Communities (ARIC) study
Respir Med
(2006)
A polymorphism in the tumor necrosis factor-alpha gene promoter region may predispose to a poor prognosis in COPD
Chest
COPD: the dangerous underestimate of 15%
Lancet
Not 15 but 50% of smokers develop COPD? Report from the Obstructive Lung Disease in Northern Sweden Studies
Respir Med
The proportional Venn diagram of obstructive lung disease: two approximations from the United States and the United Kingdom
Chest
Gender and COPD in patients attending a pulmonary clinic
Chest
Predictors of lung function and its decline in mild to moderate COPD in association with gender: results from the Euroscop study
Respir Med
Interpreting COPD prevalence estimates: what is the true burden of disease?
Chest
Chronic obstructive pulmonary disease in five Latin American cities (the PLATINO study): a prevalence study
Lancet
Comorbidity and mortality in COPD-related hospitalizations in the United States, 1979 to 2001
Chest
Pharmacoeconomic evaluation of COPD
Chest
The burden of COPD in Italy: results from the Confronting COPD survey
Respir Med
Costs of chronic obstructive pulmonary disease in Spain: estimation from a population-based study
Arch Bronconeumol
Costs of chronic bronchitis and COPD: a 1-year follow-up study
Chest
Pharmacoeconomic evaluation of acute exacerbations of chronic bronchitis and COPD
Chest
Corticosteroid resistance in chronic obstructive pulmonary disease: inactivation of histone deacetylase
Lancet
Systemic effects of COPD
Respir Med
Global burden of disease and risk factors
Global strategy for diagnosis, management, and prevention of COPD
Standards for the diagnosis and treatment of patients with COPD: a summary of the ATS/ERS position paper
Eur Respir J
Effects of smoking intervention and the use of an inhaled anticholinergic bronchodilator on the rate of decline of FEV1
JAMA
Expert panel report: guidelines for the diagnosis and management of asthma—update on selected topics 2002
Smokers with airway obstruction are more likely to quit smoking
Thorax
Long-term oxygen treatment in chronic obstructive pulmonary disease: recommendations for future research—an NHLBI workshop report
Am J Respir Crit Care Med
Systemic effects of chronic obstructive pulmonary disease
Proc Am Thorac Soc
Chronic obstructive pulmonary disease severity and cardiovascular outcomes
Eur J Epidemiol
Mechanisms and experimental models of chronic obstructive pulmonary disease exacerbations
Proc Am Thorac Soc
The body-mass index, airflow obstruction, dyspnea, and exercise capacity index in chronic obstructive pulmonary disease
N Engl J Med
A randomized trial comparing lung-volume-reduction surgery with medical therapy for severe emphysema
N Engl J Med
Early therapy improves outcomes of exacerbations of chronic obstructive pulmonary disease
Am J Respir Crit Care Med
Use of spirometry and respiratory drugs in Manitobans over 35 years of age with obstructive lung diseases
Can Respir J
The British hypothesis revisited
Eur Respir J
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