Objective: The impact of chronic obstructive pulmonary disease (COPD) is underestimation as a result of underdiagnosis and undertreatment. The objective of this study was to determine whether using spirometry to evaluate smokers enrolled in smoking cessation programs facilitates early diagnosis of COPD. Methods: The medical records of 158 smokers enrolled in the smoking cessation program at the Botucatu School of Medicine (Botucatu, Brazil) between January of 2003 and November of 2005 were evaluated retrospectively. All were over 40 years old (mean age: 55 ± 8.5 years), and 99 (62.6%) were female. We analyzed the clinical data, the previous medical diagnosis, and the spirometry results. Results: The diagnostic criteria for COPD were met by 57 (36.1%) of the 158 individuals evaluated, and 14 individuals (8.9%) were considered to be at risk for the development of the disease. Of those 57 individuals meeting the criteria for a diagnosis of COPD, 39 (68.4%) were receiving their first diagnosis of COPD, whereas 18 (31.6%) were receiving confirmation of a prior diagnosis. Of the 18 individuals previously diagnosed, 10 (56%) presented the mild/moderate form of the disease, and 8 (44%) presented the severe form. Of the 39 newly diagnosed individuals, 38 (97,4%) presented the mild/moderate for of the disease, and only 1 (2,6%) had severe COPD. Seven patients previously diagnosed with COPD presented pulmonary function test results inconsistent with the diagnostic criteria. Conclusion: Using spirometry in the initial evaluation of smokers enrolling in smoking cessation program might be a useful tool for early diagnosis of COPD.

Keywords: Smoking cessation; Spirometry; Pulmonary disease, chronic obstructive.