title: Bronchial responsiveness in bakery workers: relation to airway symptoms, IgE sensitization, nasal indices of inflammation, flour dust exposure and smoking.
abstract: BACKGROUND
  Bronchial hyperresponsiveness (BHR) is common in bakery workers. The relation between bronchial responsiveness measured with a tidal breathing method and smoking, airway symptoms, IgE-sensitization, nasal indices of inflammation and flour dust exposure have been studied with bronchial responsiveness expressed as a continuous outcome.
  
  
  METHODS
  Bakery workers (n = 197) were subjected to interviews, questionnaires, allergy tests, workplace dust measurements and bronchial metacholine provocation. Eosinophil cationic protein (ECP) and alpha(2)-macroglobulin were measured in nasal lavage. Bronchial responsiveness was expressed as slope(conc), a measurement based on regressing the per cent reduction in FEV(1) at each provocation step.
  
  
  RESULTS
  BHR expressed as slope(conc) was associated with smoking (P = 0.009), asthma symptoms at work (P = 0.001), and occupational IgE sensitization (P = 0.048). After adjusting for baseline lung function the association between BHR and IgE sensitization was no longer present. We demonstrated an association between nasal ECP and BHR (slope(conc) < 3: P = 0.012), but not to alpha(2)-macroglobulin in nasal lavage. No association was seen between BHR and current exposure level of flour dust, number of working years in a bakery or a history of dough-making.
  
  
  CONCLUSIONS
  BHR is related to baseline lung function, work-related asthma symptoms, smoking and nasal eosinophil activity, but not to occupational IgE sensitization and current flour dust exposure when measured with metacholine provocation. The slope(conc) expression seems to be a useful continuous outcome in bronchial responsiveness testing.
authors: Department of Otolaryngology, Head & Neck Surgery, Haukeland University Hospital, N-5021 Bergen, Norway. torgeir.storaas@helse-bergen.no
authors: Torgeir
authors: T
authors: Storaas
authors: Agot
authors: A
authors: Irgens
authors: Erik
authors: E
authors: Florvaag
authors: Sverre K
authors: SK
authors: Steinsvåg
authors: Laila
authors: L
authors: Ardal
authors: Thien Van
authors: TV
authors: Do
authors: Lennart
authors: L
authors: Greiff
authors: Tor B
authors: TB
authors: Aasen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001249:Asthma / Q000150:complications* / Q000453:epidemiology / Q000276:immunology / Q000503:physiopathology; D016535:Bronchial Hyperreactivity / Q000453:epidemiology / Q000276:immunology* / Q000503:physiopathology; D001985:Bronchial Provocation Tests; D016085:Bronchoconstrictor Agents; D003430:Cross-Sectional Studies; D004391:Dust; D004804:Eosinophils / Q000276:immunology; D005433:Flour / Q000009:adverse effects*; D005525:Food-Processing Industry / Q000706:statistics & numerical data; D005541:Forced Expiratory Volume; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood*; D007407:Interviews as Topic; D016210:Methacholine Chloride; D008875:Middle Aged; D017817:Nasal Lavage Fluid / Q000166:cytology / Q000276:immunology; D009664:Norway / Q000453:epidemiology; D009784:Occupational Diseases / Q000453:epidemiology / Q000276:immunology* / Q000503:physiopathology; D012220:Rhinitis / Q000150:complications* / Q000453:epidemiology / Q000276:immunology / Q000503:physiopathology; D012307:Risk Factors; D012907:Smoking / Q000009:adverse effects*; D011795:Surveys and Questionnaires; D013997:Time Factors
chemical_list: D016085:Bronchoconstrictor Agents; D004391:Dust; D016210:Methacholine Chloride; D007073:Immunoglobulin E