[Investigation on the long-term prognosis of occupational asthma]

In this report are stated the results of an investigation on the long-term prognosis of occupational asthma, recently sending out enquêtes to 28 patients with occupational asthma of various kinds who had been treated and observed in our allergy clinic these 22 years. This study is limited to 17 cases, because 4 questionnaires were not returned, 6 were sent back unopened for the reason that present address was unknown and one patient died in an accident. Eight of the patients were able to avoid exposure to allergens by changing their occupation or work place. The prognosis for these cases were quite favourable, except in one patient with double sensitization to house dust. Of the nine patients who were obliged to continue work in which they were exposed to occupational allergens, two of them benefitted from a change of the materials they used in their work to new ones free from antigenicity. However, for the rest, allergic symptoms continued with their severity for ages in inverse proportion to the the degree of effective countermeasures taken against the allergens. Accordingly, the author would assert that effective measures to improve working conditions and protect workers must be taken as soon as possible.