Dear colleagues, members of GOLD committee,
This letter arises from discussions and correspondence between colleagues involved in respiratory research or the diagnosis and treatment of lung diseases, as well as from a review of the literature on chronic obstructive pulmonary disease (COPD). As discussed below, it is written in the hope that we can persuade members of the Global Initiative for Chronic Obstructive Lung Disease (GOLD) committee to vote to change the method by which mild airway obstruction is defined by the GOLD guidelines.
We very much welcome the continued efforts of the GOLD group to stimulate interest and awareness of the high prevalence of COPD, its morbidity, effects on quality of life and on mortality. There is no doubt that COPD is a major public health problem of which the public, health workers and health authorities were insufficiently aware. It is therefore an important achievement that the World Health Organization (WHO), the European Respiratory Society (ERS), the American Thoracic Society (ATS), the Asian Pacific Society of Respirology (APSR), the Asociación Latinoamericana de Tórax (ALAT), and the World Organization of Family Doctors (WONCA) and many distinguished individuals have joined forces to increase awareness about the burden of disease, by publishing reports and guidelines for diagnostic procedures and interventions which have been adopted by numerous international and national organisations.
However, there is one area which has given rise to continuous published criticism: the criterion for confirming airway obstruction. It is well known that the forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) ratio declines with increasing age and height, even in healthy lifelong nonsmokers, in whom the lower limit of normal drops below a ratio of 0.7 from about 45 yrs of age [1–6]. It has been shown 4–27 that using the fixed ratio causes up to 50% over-diagnosis (misclassification) above that age. Adult smokers suspected of having COPD are not at increased risk of respiratory symptoms, respiratory morbidity, or all-cause mortality until the ratio falls below the age-corrected 5th percentile lower limit of the normal range 26, 28.
The present GOLD guidelines on the spirometric assessment of airway obstruction are scientifically untenable 1, 29–31 and have given rise to editorials in Chest 32, the European Respiratory Journal 17, the American Journal of Respiratory and Critical Care Medicine 33, COPD: Journal of Chronic Obstructive Pulmonary Disease 34, and Respiratory Care 35, with a plea for revision. The very significant over-diagnosis in elderly subjects due to this guideline is akin to selling sickness. There is considerable psychological impact, and there are wider health consequences of incorrectly being labelled as having COPD, a syndrome associated with a poor prognosis with regard to morbidity, quality of life and mortality and therefore a psychological burden for the subject, his family and wider environment. Subjects erroneously labelled become a target for individual and lifelong interventions which are associated with side-effects. This is all the more unacceptable since evidence for the long-term effectiveness of treatment of mild COPD, apart from smoking cessation, is lacking 28, 36. Erroneous interventions also constitute an unnecessary financial burden for society.
We applaud the GOLD committee for raising interest in COPD research. However, over-diagnosis will lead to the inclusion of subjects who do not have COPD into the research pool, thereby adding noise to any signals that researchers are looking for when trying to unravel the causes of COPD and hence find potential treatments. Also problematic is excluding younger subjects who may have airway obstruction (false negatives) when the fixed ratio is used 4, 5, 10, 16, 18, 21, 37–40. For research purposes, it is far better to limit recruitment to subjects who definitely have the disease, but this urgently requires adjustment of the present guideline on a fixed FEV1/FVC ratio.
We appreciate the consequences of changing course when so many societies and organisations will be affected by replacing the fixed ratio by the lower limit of normal, and more importantly general practitioners and clinicians may have to review and revise previous diagnoses. However, in the light of new evidence it is never too late to change a decision made in good faith. We are therefore appealing to you, members of the GOLD committees, to change the method by which mild airway obstruction is defined by the GOLD guidelines in order to abandon the fixed ratio forever in favour of the lower limit of normal.
Acknowledgments
Organisations endorsing this open letter
ANZSRS: Australian and New Zealand Society of Respiratory Science. ARTP: Association for Respiratory Technology and Physiology. CAHAG: COPD & Astma Huisartsen Advies Groep (COPD & Asthma GP Advisory Group). SKL: Dutch Paediatric Repiratory Society. Education for Health, Warwick, UK. National Respiratory Training Center, Suffolk, VA, USA. NHG: Nederlands Huisartsen Genootschap (Dutch Society of GPs). NVALT: Dutch Thoracic Society. NVLA: Nederlandse Vereniging Longfunctie Analisten (Dutch Society of Respiratory Technicians). French Physiological Society. PCRS – UK: Primary Care Respiratory Society United Kingdom. SPLF: Société Scientifique de Médecine Générale. SSMG: Société Scientifique de Médecine Générale. WONCA: World Organization of Family Doctors.
Individuals endorsing this open letter
S. Aaron, Ottawa, Canada. P. Adab, Birmingham, UK. S.K. Agarwal, Raleigh-Durham, NC, USA. A.N. Aggarwal, Chandigarh, India. O.A. Al-Rawas, Muscat, Oman. S.C. Arce, Buenos Aires, Argentina. B.G.M. Arets, Utrecht, the Netherlands. B. Bake, Göteborg, Sweden. L. Beckert, Christchurch, New Zealand. H.B. Saad, Sousse, Tunisia. N. Berend, Sydney, Australia. J.W. van den Berg, Zwolle, the Netherlands. E. Berglund, Gothenburg, Sweden. F. Blasi, Milan, Italy. P.W. Boros, Warsaw, Poland. O. Brändli, Wald, Switzerland. P-O. Bridevaux, Geneva, Switzerland. P.J. Briffa, Camperdown, Australia. B. Brockway, Dunedin, New Zealand. M. Brown, Brisbane, Australia. M. Bucknall, London, UK. J. Buffels, Leuven, Belgium. F.B. Rincón, Barcelona, Spain. D. Burton, Rockhampton, Australia. J. Canterbury, Denver, CO, USA. R. Casaburi, Torrance, CA, USA. M. Cazzola, Rome, Italy. S. Centanni, Milan, Italy. I. Cerveri, Pavia, Italy. J. Concato, New Haven, CT, USA. B.G. Cooper, Birmingham, UK. A.S. Copur, North Chicago, IL, USA. A.G. Corsico, Pavia, Italy. J. Cotes, Durham, UK. D. Cramer, London, UK. A.J. Crockett, Adelaide, Australia. B.H. Culver, Seattle, WA, USA. R.E. Dales, Ottawa, ON, Canada. W. Dejsomritrutai, Bangkok, Thailand. P.N. Richard Dekhuijzen, Nijmegen, the Netherlands. E. Del Colle, Box Hill, Australia. H. Dunroy, Dunedin, New Zealand. D. Figurski, Canberra, Australia. M.J. Fletcher, Warwick, UK. C.A. Vaz Fragoso, New Haven, CT, USA. A. Fulambarker, Chicago IL, USA. K. Gain, Perth, Australia. M. Gappa, Wesel, Germany. M.W. Gerbase, Geneva, Switzerland. J. Gibson, Newcastle upon Tyne, UK. T.M. Gill, New Haven, CT, USA. K. Gooey, Victoria, Australia. C.J. Gore, Canberra, Australia. G. Hall, Perth, Australia. J.E. Hansen, Torrance, CA, USA. J.A. Hardie, Bergen, Norway. J. Henderson, Bristol, UK. E. Hnizdo, Morgantown, WV, USA. G. Hollaert, Dottignies, Belgium. S. Holmes, Shepton Mallet, UK. F. Hoppin, Pawtucket, RI, USA. B. Houltz, Gothenburg, Sweden. A. Houtkooper, Den Helder, the Netherlands. M. Hughes, London, UK. G. Hülskamp, Münster, Germany. M. Hurwitz, Canberra, Australia. R. Hyatt, Rochester, MN, USA. C.G. Irvin, Burlington, VT, USA. D.P. Johns, Hobart, Australia. R.E. Kanner, Salt Lake City, UT, USA. H. Khaled, Ksar Hellal, Tunisia. J. Kirkby, London, UK. J. Kivastik, Tartu, Estonia. D. Köhler, Kloster Grafschaft, Germany. N. Künzli, Basel, Switzerland. S.M. Lam, Hong Kong, China. A. Langhammer, Levanger, Norway. L.T. Tuyet Lan, Ho Chi Min City, Vietnam. A.C.W. Lau, Hong Kong, China. M.L. Levy, Kenton, UK. C. Lisboa, Santiago, Chile. S. Lum, London, UK. N. MacIntyre, Durham, NC, USA. P.T. Macklem, Montreal, Canada. Y. Martinet, Nancy, France. G. McAvay, New Haven, CT, USA. J. McLachlan, Hamilton, New Zealand. A. Medbø, Tromsø, Norway. R.B. Mellins, New York, NY, USA. P.J.F.M. Merkus, Nijmegen, the Netherlands. A. Miller, New York, NY, USA. C. Mottram, Rochester, MN, USA. P. Myrianthefs, Kifissia, Greece. J. Olofson, Gothenburg, Sweden. S. Ostrowski, Lublin, Poland. S. Pakhalé, Ottawa, ON, Canada. R. Pellegrino, Cuneo, Italy. C.A.C. Pereira, São Paulo, Brazil. E.L. Petsonk, MD, Morgantown, WV, USA. F. Pistelli, Pisa, Italy. K.V.V. Prasad, Hyderabad, India. J. Pray, Minneapolis, MN, USA. J.J. Pretto, Newcastle, Australia. C. Que, Beijing, China. S. Raju, Hyderabad, India. R.G. Roberts, Madison, WI, USA. N. Rothe, Paris, France. L. Rodwell, Brisbane, Australia. D. Robiony-Rogers, Wellington, Australia. M. Rosenfeld, Seattle, WA, USA. B. Rottier, Groningen, the Netherlands. S. Rouatbi, Sousse, Tunisia. R.E.K. Russell, London, UK. M. Rutten-van Mölken, Maastricht, the Netherlands. P.D. Scanlon, Rochester, MN, USA. O. van Schayck, Maastricht, the Netherlands. T. Schermer, Nijmegen, the Netherlands. P. Serrier, Paris, France. T. Similowski, Paris, France. I.R. Small, Aberdeen, UK. H. Stam, Rotterdam, the Netherlands. S. Stanojevic, London, UK. I. Steenbruggen, Zwolle, the Netherlands. P.S. Stephenson, Haverhill, Suffolk, UK. C. Straus, Paris, France. J. Sullivan, New York, NY, USA. M. Sunitha, Hyderabad, India. A. De Sutter, Ghent, Belgium. G.W. Sybrecht, Homburg/Saar, Germany. R.Taylor, Dunedin, New Zealand. F. Thien, Melbourne, Australia. B.R. Thompson, Melbourne, Australia. W. Tomalak, Rabka, Poland. D. Valeyre, Bobigny, France. P.H. Van Ness, New Haven, CT, USA. C. van Weel, Nijmegen, the Netherlands. J. Vandevoorde, Brussels, Belgium. D. Vilozni, Tel Aviv, Israel. W.M. Vollmer, Portland, OR, USA. K. Wasserman, Torrance, CA, USA. S.N. West, Sydney Australia. P. White, London, UK. L. Wilson, Invercargill, New Zealand. C. Wong, Dunedin, New Zealand. E.F.M. Wouters, Maastricht, the Netherlands. J. Zieliński, Warsaw, Poland.
Footnotes
This open letter has been previously published in the Primary Care Respiratory Journal (Prim Care Respir J 2010; 19: 288−291), Respiration (Respiration 2010; 80: 265–268), Respiratory Care (Respir Care 2010; 55: 1397–1398), Revues des Maladies Respiratoires (Rev Mal Respir 2010; 27: 1003–1007) and on the website of the Association for Respiratory Technology and Physiology (www.artp.org.uk).
Statement of Interest
Statements of interest for M.R. Miller and P.L. Enright can be found at www.erj.ersjournals.com/site/misc/statements.xhtml
- ©ERS 2011
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