Abstract

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: Our aim was 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 term sensitiser induced asthma and acute irritant induced asthma (RADS); acute irritant induced asthma (RADS) 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.