Controversies in the use of spirometry for early recognition and diagnosisof chronic obstructive pulmonary disease in cigarette smokers

Cigarette smokers may develop symptoms of chronic obstructive pulmonary dis ease (COPD) within years of starting smoking but the cough and sputum produ ction are usually ignored by the smoker land often by their physicians) as normal for a smoker and no intervention is deemed necessary. The disease is usually not diagnosed until the smoker experiences symptoms (usually short ness of breath with mild exertion) that interfere with quality of life. Unf ortunately, dyspnea on mild exertion does not occur until only about half o f lung function remains and COPD has become moderately severe. Experts agre e it would be desirable to have some test or intervention that would allow early identification of COPD, enabling earlier treatment or prevention of m ore severe stages of the disease. There is tremendous controversy as to whe ther spirometry is that test. This article discusses the controversy and th e rationale for the authors' recommendation that spirometry be used to scre en middle-aged smokers. A 1984 editorial in the journal Chest stated that screening adult cigarette smokers with spirometry would be a very expensive "stage prop" to Il[wave] before a smoker in an effort to scare him into quitting."(16a) The authors argued against the use of screening spirometry, emphasizing that (1) It is not at all clear that changes in the small airways presage COPD. (2) Indiv iduals cannot be identified as losing function faster than others ("rapid f allers") on the basis of a low forced expiratory Volume in 1 second (FEV,) alone. (3) COPD accounts for only a small fraction of deaths from smoking i n the United States. (4) The 75% of smokers who have normal spirometry may be led to believe that smoking is safe for them. And (5) medical and econom ic resources are limited, and screening all adult smokers in the United Sta tes would cost about half a billion dollars. The authors concluded the best intervention physicians could make was to tell all patients who smoke ciga rettes that they should stop. Several other position papers and disease management guidelines have also e ither not recommended, or have not mentioned, spirometry as a screening tes t for COPD. The 1983 American Thoracic Society (ATS) statement on screening for adult respiratory disease(2) stated "the lack of specific, effective t herapeutic intervention (aside from smoking cessation) limits the need for spirometric screening of the general population (for COPD)." The ATS statem ent, however, made a clear distinction between population screening and cli nical case finding in the setting of an individual, patient who seeks medic al attention from a physician. The statement suggested that, in the context of a clinical examination, screening spirometry might be considered in hig h-risk patients.(2) Recent consensus statements on managing COPD did not ev en address the early assessment of respiratory function in patients at risk for COPD.(4) A 1997 review asked, "Is screening for COPD justified?" and c oncluded: "There is no evidence that spirometry, as an isolated interventio n aids smoking cessation."(6) None of the evidence-based preventive guideli nes currently recommend spirometry testing for smokers(40) and very few pri mary care physicians perform spirometry tests for smokers.(26, 30, 42) Despite the controversy, a 2000 consensus statement from the National Lung Health Education Program (NLHEP) recommended the widespread use of office s pirometry by primary care providers for patients at high risk of developing COPD (those over age 44 who smoke cigarettes and have respiratory symptoms ).(16) The NLHEP is a nonprofit group, organized and chaired by Tom Petty, MD in Denver, Colorado, that promotes early detection and treatment of COPD by primary care providers.(32) Both authors of this review are members of the spirometry subcommittee of the NLHEP; one co-authored a 1987 book that encouraged spirometry for the early detection of COPD.(13) The recommendati ons in the report were agreed upon only after extensive discussion and many modifications to the original draft of the document.