Bronchial responsiveness in bakery workers: relation to airway symptoms, IgE sensitization, nasal indices of inflammation, flour dust exposure and smoking.
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.
Storaas
Torgeir
T
Department of Otolaryngology, Head & Neck Surgery, Haukeland University Hospital, N-5021 Bergen, Norway. torgeir.storaas@helse-bergen.no
Irgens
Agot
A
Florvaag
Erik
E
Steinsvåg
Sverre K
SK
Ardal
Laila
L
Do
Thien Van
TV
Greiff
Lennart
L
Aasen
Tor B
TB
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
D016085:Bronchoconstrictor Agents; D004391:Dust; D016210:Methacholine Chloride; D007073:Immunoglobulin E