Clinical trial NCT01602237: Preventing Respiratory Health Problems in Bakery Employees
Official title: Preventing Respiratory Health Problems in Bakery Employees.
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Chronic Obstructive Lung Disease
Rhinitis
Lead sponsor: Haukeland University Hospital
Sponsor class: OTHER
First posted: 2012-05-18
Enrollment: 253
Sex: ALL
Minimum age (years): 18
Maximum age (years): 80
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: OTHER
Sampling method: PROBABILITY_SAMPLE
Study population: 1. All the employees in 5 bakeries investigated in 1999-2002 (one of the original 6 bakeries has fused with one of the others)
2. All the employees in additional 2 bakeries located in the same Hordaland county, Norway, as the other 5 bakeries

Brief summary: The study is a follow-up of investigations done in the years 1999-2002 in bakery employees. The main purposes are to look at the associations between flour dust exposure and respiratory disease, and to find out the best ways to reduce the flour dust levels in the working environment.

Detailed description: Background and Methods:

Supported by the The Confederation of Norwegian Enterprise (CNBI) Working Environment Fund a follow-up study of 184 bakery workers in 5 bakeries was done in 2012, appr. 10 years after a similar study in 1999-2002. In addition a cross-sectional study in 2 other bakeries (one 'bread-factory', and a traditional bakery with three small bake shops) was added.

Altogether 253 participants, among them 61 former bakery workers, were investigated with use of questionnaires, allergy-testing (skin prick testing, and blood samples for specific IgE and total IgE), spirometry with reversibility testing, exhaled NO-measurement, and nasal measurements.

As in 1999-2002 an extensive exposure assessment was performed including personal samples of total dust (Gelman), inhalable dust (PAS6), as well as direct reading measurements of dust (Dust Track). A Job Exposure Matrix (JEM) was created enabling each participant to be assigned an exposure value of probable mean daily flour-dust exposure based on work-tasks and bakery.

Aim of study:

* Follow-up of the participants in the 1999-2002 study, both still active bakery workers and former workers, on health-status focusing on respiratory disease, sensitization to common and occupational allergens, level of sick-leave and reasons for quitting as a baker.
* Inclusion of 'new' bakery workers into the cohort as a cross-sectional study, and to compare health-status in two cross-sectional cohorts.
* To assess personal exposure to flour-dust among workers in 7 bakeries, as part of the cross-sectional study described above.
* To identify implemented flour-dust exposure reduction measures in bakeries participating in 1999-2002, and to assess the potential impact of these measures on the exposure to flour dust.

Eligibility criteria: Inclusion Criteria:

* Employed in a bakery for more than 6 months
* and/or participant of the investigations done in 1999-2002 in 6 bakeries

Primary outcomes:
measure: Forced Exhaled Volume in one second (FEV1)
timeFrame: Change/decline from 1999-2002 to 2012
Secondary outcomes:
measure: Forced Vital Capacity (FVC)
timeFrame: Each participant will be investigated once. Anticipated recruitment time for the whole cohort (study population I and II): about 10 months.
measure: Inflammation markers in nasal lavage
timeFrame: Each participant will be investigated once. Anticipated recruitment time for the whole cohort (study population I and II): about 10 months.
measure: Specific IgE
timeFrame: Each participant will be investigated once. Anticipated recruitment time for the whole cohort (study population I and II): about 10 months.
measure: Skin reaction to prick testing with allergen extracts
timeFrame: Each participant will be investigated once. Anticipated recruitment time for the whole cohort (study population I and II): about 10 months.
Other outcomes:
Locations:
city: Bergen
country: Norway
facility: Dept. of Occupational Medicine, Haukeland University Hospital
Study officials:
affiliation: Haukeland University Hospital
name: Torgeir Storaas, PhD, MD
role: PRINCIPAL_INVESTIGATOR
affiliation: Haukeland University Hospital
name: Tor B Aasen, MD
role: STUDY_DIRECTOR
References:
citation: Storaas T, Irgens A, Florvaag E, Steinsvag SK, Ardal L, Do TV, Greiff L, Aasen TB. Bronchial responsiveness in bakery workers: relation to airway symptoms, IgE sensitization, nasal indices of inflammation, flour dust exposure and smoking. Clin Physiol Funct Imaging. 2007 Sep;27(5):327-34. doi: 10.1111/j.1475-097X.2007.00755.x.
citation: Storaas T, Ardal L, Van Do T, Florvaag E, Steinsvag SK, Irgens A, Aasen TB, Greiff L. Nasal indices of eosinophilic and exudative inflammation in bakery-workers. Clin Physiol Funct Imaging. 2007 Jan;27(1):23-9. doi: 10.1111/j.1475-097X.2007.00707.x.
citation: Storaas T, Steinsvag SK, Florvaag E, Irgens A, Aasen TB. Occupational rhinitis: diagnostic criteria, relation to lower airway symptoms and IgE sensitization in bakery workers. Acta Otolaryngol. 2005 Nov;125(11):1211-7. doi: 10.1080/00016480510044205.
citation: Kirkeleit J, Hollund BE, Riise T, Eduard W, Bratveit M, Storaas T. Bakers' exposure to flour dust. J Occup Environ Hyg. 2017 Feb;14(2):81-91. doi: 10.1080/15459624.2016.1225156.