Defining and investigating occupational asthma: a consensus approach
- H C Francis1,
- C O Prys-Picard1,
- D Fishwick2,
- C Stenton3,
- P S Burge4,
- L M Bradshaw2,
- J G Ayres5,
- S M Campbell6,
- R McL Niven1
- 1North West Lung Research Centre, Wythenshawe Hospital, Manchester, UK
- 2Centre for Workplace Health, Health & Safety Laboratory, Buxton & University of Sheffield, UK
- 3Royal Victoria Infirmary, Newcastle upon Tyne, UK
- 4Occupational Lung Disease Unit, Birmingham Heartlands Hospital, Birmingham, UK
- 5Department of Environmental and Occupational Medicine, University of Aberdeen, UK
- 6National Primary Care Research and Development Centre, University of Manchester, UK
- Correspondence to: Dr H Francis North West Lung Research Centre, Wythenshawe Hospital, Southmoor Road, Manchester M23 9LT, UK;
- Accepted 27 October 2006
- Published Online First 27 November 2006
Background: At present there is no internationally agreed definition of occupational asthma and there is a lack of guidance regarding the resources that should be readily available to physicians running specialist occupational asthma services.
Aims: To agree a working definition of occupational asthma and to develop a framework of resources necessary to run a specialist occupational asthma clinic.
Method: A modified RAND appropriateness method was used to gain a consensus of opinion from an expert panel of clinicians running specialist occupational asthma clinics in the UK.
Results: Consensus was reached over 10 terms defining occupational asthma including: occupational asthma is defined as asthma induced by exposure in the working environment to airborne dusts vapours or fumes, with or without pre-existing asthma; occupational asthma encompasses the terms “sensitiser-induced asthma” and “acute irritant-induced asthma” (reactive airways dysfunction syndrome (RADS)); acute irritant-induced asthma is a type of occupational asthma where there is no latency and no immunological sensitisation and should only be used when a single high exposure has occurred; and the term “work-related asthma” can be used to include occupational asthma, acute irritant-induced asthma (RADS) and aggravation of pre-existing asthma. Disagreement arose on whether low dose irritant-induced asthma existed, but the panel agreed that if it did exist they would include it in the definition of “work-related asthma”. The panel agreed on a set of 18 resources which should be available to a specialist occupational asthma service. These included pre-bronchodilator FEV1 and FVC (% predicted); peak flow monitoring (and plotting of results, OASYS II analysis); non-specific provocation challenge in the laboratory and specific IgE to a wide variety of occupational agents.
Conclusion: It is hoped that the outcome of this process will improve uniformity of definition and investigation of occupational asthma across the UK.
Published Online First 23 November 2007
Competing interests: None.