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Original article
Chronic obstructive pulmonary disease mortality and prevalence: the associations with smoking and poverty—a BOLD analysis
  1. Peter Burney1,
  2. Anamika Jithoo1,
  3. Bernet Kato1,
  4. Christer Janson2,
  5. David Mannino3,
  6. Ewa Niżankowska-Mogilnicka4,
  7. Michael Studnicka5,
  8. Wan Tan6,
  9. Eric Bateman7,
  10. Ali Koçabas8,
  11. William M Vollmer9,
  12. Thorarrin Gislason10,
  13. Guy Marks11,
  14. Parvaiz A Koul12,
  15. Imed Harrabi13,
  16. Louisa Gnatiuc1,
  17. Sonia Buist14,
  18. for the Burden of Obstructive Lung Disease (BOLD) Study
  1. 1National Heart & Lung Institute, Imperial College, London, UK
  2. 2Department of Medical Sciences: Respiratory Medicine & Allergology, Uppsala University, Uppsala, Sweden
  3. 3University of Kentucky, Lexington, Kentucky, USA
  4. 4Jagiellonian University School of Medicine, Cracow, Poland
  5. 5Department of Pulmonary Medicine, Paracelsus Medical University, Salzburg, Austria
  6. 6University of British Columbia, Vancouver, British Columbia, Canada
  7. 7University of Cape Town Lung Institute, Cape Town, South Africa
  8. 8Cukurova University School of Medicine, Adana, Turkey
  9. 9Kaiser Permanente Center for Health Research, Portland, Oregon, USA
  10. 10Landspitali University Hospital, Reykjavik, Iceland
  11. 11Woolcock Institute of Medical Research, Sydney, Australia
  12. 12Sher-i-Kashmir Institute of Medical Sciences, Srinagar, Jammu and Kashmir, India
  13. 13Faculté de Médecine, Sousse, Tunisia
  14. 14Oregon Health & Sciences University, Portland, Oregon, USA
  1. Correspondence to Professor Peter Burney, National Heart & Lung Institute, Imperial College, 1 Manresa Road, London SW3 6LR, UK; p.burney{at}


Background Chronic obstructive pulmonary disease (COPD) is a commonly reported cause of death and associated with smoking. However, COPD mortality is high in poor countries with low smoking rates. Spirometric restriction predicts mortality better than airflow obstruction, suggesting that the prevalence of restriction could explain mortality rates attributed to COPD. We have studied associations between mortality from COPD and low lung function, and between both lung function and death rates and cigarette consumption and gross national income per capita (GNI).

Methods National COPD mortality rates were regressed against the prevalence of airflow obstruction and spirometric restriction in 22 Burden of Obstructive Lung Disease (BOLD) study sites and against GNI, and national smoking prevalence. The prevalence of airflow obstruction and spirometric restriction in the BOLD sites were regressed against GNI and mean pack years smoked.

Results National COPD mortality rates were more strongly associated with spirometric restriction in the BOLD sites (<60 years: men rs=0.73, p=0.0001; women rs=0.90, p<0.0001; 60+ years: men rs=0.63, p=0.0022; women rs=0.37, p=0.1) than obstruction (<60 years: men rs=0.28, p=0.20; women rs=0.17, p<0.46; 60+ years: men rs=0.28, p=0.23; women rs=0.22, p=0.33). Obstruction increased with mean pack years smoked, but COPD mortality fell with increased cigarette consumption and rose rapidly as GNI fell below US$15 000. Prevalence of restriction was not associated with smoking but also increased rapidly as GNI fell below US$15 000.

Conclusions Smoking remains the single most important cause of obstruction but a high prevalence of restriction associated with poverty could explain the high ‘COPD’ mortality in poor countries.

  • COPD epidemiology
  • Tobacco and the lung
  • Lung Physiology

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