Prevalence of asthma and wheezes among snow crab workers in western Japan : a cross-sectional study

Objectives : Few reports are available concerning the prevalence of asthma among snow crab workers in Japan. The object of this study was to estimate the prevalence of asthma and wheezes among Japanese snow crab workers and their associations with exhaled nitric oxide (FeNO) and YKL-40. Methods : Forty-nine snow crab workers enrolled in this study, which was cross-sectional by design and was conducted using a translated version of the European Community Respiratory Health Survey questionnaire. The levels of FeNO and serum YKL-40 were measured between September and October 2014. Results : The prevalences of current asthma and wheezes were 10.2% (95% CI, 3.4 to 22.2) and 12.2% (95% CI, 4.6 to 24.8), respectively. There was no association between these prevalences and the duration of snow crab employment. Six subjects’ FeNO levels exceeded 50 ppb, and nine subjects’ levels exceeded 25 ppb. Twelve subjects’ (25.5%) serum YKL-40 levels exceeded 77.2 ng/mL, which was 2 standard deviations above the mean for healthy subjects. However, there were no significant relationships among the prevalences for asthma and wheezes, FeNO, and serum YKL-40. Conclusions : This study provides information concerning the prevalences of asthma and wheezes among Japanese snow crab processing workers.