title: Pulmonary function predicting confirmed recovery from lower-respiratory symptoms in World Trade Center-exposed firefighters, 2001 to 2010.
abstract: BACKGROUND
  We examined the relationship between pulmonary function (FEV 1 ) and confirmed recovery from three lower-respiratory symptoms (LRSs) (cough, dyspnea, and wheeze) up to 9 years after symptom onset.
  
  
  METHODS
  The study included white and black male World Trade Center (WTC)-exposed firefighters who reported at least one LRS on a medical monitoring examination during the fi rst year after September 11, 2001. Confirmed recovery was defined as reporting no LRSs on two consecutive and all subsequent examinations. FEV 1 was assessed at the fi rst post-September 11, 2001, examination and at each examination where symptom information was ascertained. We used stratified Cox regression models to analyze FEV 1 , WTC exposure, and other variables in relation to confirmed symptom recovery.
  
  
  RESULTS
  A total of 4,368 fi refighters met inclusion criteria and were symptomatic at year 1, of whom1,592 (36.4%) experienced confirmed recovery. In univariable models, fi rst post-September 11,2001, concurrent, and difference between fi rst post-September 11, 2001, and concurrent FEV 1 values were all significantly associated with confirmed recovery. In adjusted analyses, both fi rst post-September 11, 2001, FEV 1 (hazard ratio [HR], 1.07 per 355-mL difference; 95% CI, 1.04-1.10) and FEV 1 % predicted (HR, 1.08 per 10% predicted difference; 95% CI, 1.04-1.12) predicted confirmed recovery. WTC exposure had an inverse association with confirmed recovery in the model with FEV 1 , with the earliest arrival group less likely to recover than the latest arrival group (HR, 0.73;95% CI, 0.58-0.92).
  
  
  CONCLUSIONS
  Higher FEV 1 and improvement in FEV 1 after September 11, 2001, predicted confirmed LRS recovery, supporting a physiologic basis for recovery and highlighting consideration of spirometry as part of any postexposure respiratory health assessment.
authors.affiliation: Department of Medicine, Montefiore Medical Center, Bronx, NY; Bureau of Health Services, Fire Department of the City of New York, Brooklyn, NY.
authors.forename: Jackie
authors.initials: J
authors.lastname: Soo
authors.affiliation: Department of Epidemiology and Population Health, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, NY; Bureau of Health Services, Fire Department of the City of New York, Brooklyn, NY. Electronic address: webberm@fdny.nyc.gov.
authors.forename: Mayris P
authors.initials: MP
authors.lastname: Webber
authors.affiliation: Department of Epidemiology and Population Health, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, NY.
authors.forename: Charles B
authors.initials: CB
authors.lastname: Hall
authors.affiliation: Department of Epidemiology and Population Health, Montefiore Medical Center and Albert Einstein College of Medicine, Bronx, NY.
authors.forename: Hillel W
authors.initials: HW
authors.lastname: Cohen
authors.affiliation: Department of Medicine, Montefiore Medical Center, Bronx, NY; Bureau of Health Services, Fire Department of the City of New York, Brooklyn, NY.
authors.forename: Theresa M
authors.initials: TM
authors.lastname: Schwartz
authors.affiliation: Bureau of Health Services, Fire Department of the City of New York, Brooklyn, NY.
authors.forename: Kerry J
authors.initials: KJ
authors.lastname: Kelly
authors.affiliation: Department of Medicine, Montefiore Medical Center, Bronx, NY; Bureau of Health Services, Fire Department of the City of New York, Brooklyn, NY.
authors.forename: David J
authors.initials: DJ
authors.lastname: Prezant
mesh_terms: D000328:Adult; D003371:Cough; D004417:Dyspnea; D061388:Firefighters; D006801:Humans; D008171:Lung Diseases / Q000209:etiology / Q000503:physiopathology*; D008297:Male; D009519:New York City; D009784:Occupational Diseases / Q000209:etiology / Q000503:physiopathology*; D016273:Occupational Exposure / Q000009:adverse effects*; D011237:Predictive Value of Tests; D016016:Proportional Hazards Models; D020127:Recovery of Function; D012129:Respiratory Function Tests; D012135:Respiratory Sounds; D047851:September 11 Terrorist Attacks; D011795:Surveys and Questionnaires