Journal Club - Overdiagnosis of COPD with Unobstructed Spirometry


Calgary, Alberta


Feb 8, 2019

Topic:  Overdiagnosis of COPD in Subjects with Unobstructed Spirometry – a BOLD analysis
ReferenceCHEST 2019
Lead by:  Dr. Olga Tourin MD, FRCP, FCCP, FACP, Dipl ABIM (IM)
Duration:   45   minutes
Discussion:  The study reported the overdiagnosis of COPD and the prevalence of spirometrically defined false positive COPD, as well as their relationship with overtreatment in a cross-sectional epidemiologic study. Among  16, 177 participants, 919 (5.7%) reported a previous medical diagnosis of COPD. Post broncho-dilator spirometry was unobstructed in 569 subjects  (61.9%) - false positive COPD. A similar rate in over-diagnosis was seen when using the fixed ratio criterion (53.3%). Inn multivariate analysis, overdiangosis was most common among women and was associated with high education, former and current smoking, presence of wheeze, cough and phlegm and concomitant medical diagnosis of asthma or heart disease. Among the subjects with false positive COPD, 45.7% reported current use of respiratory medication. Excluding patients with reported asthma, still 34.4% of those with normal spirometry used a respiratory medication.
Conclusion: The authors concluded that false positive COPD is frequent and was often associated with overtreatment.