A novel method for estimating the effects of job conditions on asthma and chronic lung disease

Objective: This study uses 32 years of longitudinal job history to analyze the long-term effect of exposure to specific workplace conditions on the risk of contracting asthma or chronic lung disease later in life. Our approach allows for the estimation of occupational respiratory risks even in the absence of direct environmental monitoring. Methods: We employ a novel methodology utilizing data from the National Longitudinal Survey of Youth 1979 (NLSY79), and ratings of job exposures from the Occupational Information Network (O∗NET), which are based on 70 years of empirical data compiled by the U.S. Department of Labor. A series of multivariable logistic regression analyses are performed to determine how long-term exposure to a particular occupational O∗NET indicator (e.g., working in an extremely hot or cold environment) is related to asthma and COPD risk. Results: The risk of contracting COPD was significantly associated with long-term work in very hot or cold temperatures (OR=1.50, CI: 1.07-2.10), performing physically demanding activities (OR=1.65, CI:1.20-2.28), working outdoors exposed to weather (OR=1.45, CI:1.06-1.99), and workplace exposure to contaminants (OR=1.42, CI:1.05-1.96). In general, the effects of exposure were greater for COPD than for asthma. With respect to contracting asthma, only exposure to work in very hot or cold temperatures (OR=1.35, CI:1.08-1.70) and performing physically demanding activities (OR=1.23, CI:1.00-1.52) were statistically significant. Conclusions: Use of O∗NET job descriptors as surrogate measures of workplace exposures can provide a useful way of analyzing the risk of occupationally-related respiratory disease in situations where direct exposure measurement is not feasible.