title: Persistent Empiric COPD Diagnosis and Treatment After Pulmonary Function Test Showed No Obstruction.
abstract: BACKGROUND
  Health-care providers often diagnose and empirically treat COPD without a confirmative pulmonary function test (PFT) or even despite a PFT that is not diagnostic of obstructive lung disease. We hypothesized that a portion of patients continue to carry a persistent empiric COPD diagnosis and receive treatment with bronchodilators and inhaled steroids after a PFT shows no obstruction.
  
  
  METHODS
  We retrospectively reviewed single PFT sessions with both spirometry and plethysmography in 1,805 subjects. We included subjects who had a normal PFT or a restrictive ventilatory defect. Persistent empiric COPD diagnosis and treatment were defined when subjects with normal PFTs or a restrictive ventilatory defect continued to carry a health-care provider COPD diagnosis or receive treatment with bronchodilators and/or inhaled glucocorticoids, respectively, after a PFT showed no obstruction.
  
  
  RESULTS
  One quarter of subjects with FEV1/FVC ≥ lower limit of the normal range had nonspecific PFT abnormalities. We included 473 subjects with normal PFTs and 382 with a restrictive ventilatory defect (n = 855). Persistent empiric COPD diagnosis (60 of 855, 7% prevalence) was associated with current (odds ratio [OR] = 44.7, P < .001) and former smoking (OR = 17.3, P < .001) and older age (OR = 1.03/y, P = .005). Persistent empiric treatment (208 of 855, 24%) was associated with empiric COPD diagnosis (OR = 24.6, P < .001), female sex (OR = 1.75, P = .002), current (OR = 2.04, P = 0.040) and former smoking (OR = 1.53, P = 0.029), interstitial lung disease (OR = 2.09, P = .001), other respiratory diagnosis (OR = 3.17, P < .001), and obstructive sleep apnea (OR = 1.79, P = .006).
  
  
  CONCLUSIONS
  Persistent empiric COPD diagnosis was 7%, but persistent empiric treatment was common.
authors.affiliation: Division of Pulmonary and Critical Care, Department of Medicine, University of Minnesota, Minneapolis, Minnesota. spyridon-fortis@uiowa.edu.
authors.forename: Spyridon
authors.initials: S
authors.lastname: Fortis
authors.affiliation: Pulmonary Function Test Laboratory, University of Minnesota Medical Center, Minneapolis, Minnesota.
authors.forename: Edward O
authors.initials: EO
authors.lastname: Corazalla
authors.affiliation: Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, Minnesota.
authors.forename: David R
authors.initials: DR
authors.lastname: Jacobs
authors.affiliation: Pulmonary Function Test Laboratory, University of Minnesota Medical Center, Minneapolis, Minnesota. Division of Pulmonary and Critical Care, Department of Medicine, University of Minnesota, Minneapolis, Minnesota.
authors.forename: Hyun J
authors.initials: HJ
authors.lastname: Kim
mesh_terms: D000328:Adult; D000367:Age Factors; D000368:Aged; D001993:Bronchodilator Agents / Q000627:therapeutic use*; D003951:Diagnostic Errors; D005260:Female; D005541:Forced Expiratory Volume; D005938:Glucocorticoids / Q000627:therapeutic use*; D006801:Humans; D017563:Lung Diseases, Interstitial / Q000503:physiopathology; D008297:Male; D008485:Medical Audit; D008875:Middle Aged; D010991:Plethysmography; D029424:Pulmonary Disease, Chronic Obstructive / Q000175:diagnosis* / Q000188:drug therapy* / Q000503:physiopathology; D012189:Retrospective Studies; D012737:Sex Factors; D020181:Sleep Apnea, Obstructive / Q000503:physiopathology; D012907:Smoking / Q000503:physiopathology; D013147:Spirometry; D014797:Vital Capacity
chemical_list: D001993:Bronchodilator Agents; D005938:Glucocorticoids
keywords: COPD; diagnosis; diagnostic errors; plethysmography; pulmonary function tests; spirometry