The association of effort-reward imbalance and asthma: findings from two cross-sectional studies.

Purpose: There is evidence to suggest that work stress is positively associated with the occurrence of asthma. A limitation is that the small number of prior studies utilized unestablished work stress measures, thus constraining interpretation and generalizability. The present study re-examined this association by assessing work stress based on the well-established effort-reward imbalance (ERI) model. Methods: We drew on data from two cross-sectional studies. Study 1 was conducted in a large pharmaceutical company in 2013 ( n = 1,464). Study 2 was based on data from the 2011 wave of the population-based German Socio-Economic Panel ( n = 8,388). ERI was assessed by validated questionnaires. Asthma was determined by self-report of a physician-based diagnosis. Associations between ERI or its subcomponents 'effort', 'reward' and 'overcommitment' ( z scores or categorized) with asthma were estimated by logistic regression models and reported as adjusted odds ratios (ORs) with 95 % confidence intervals (CIs). Results: A one standard deviation increase of the ERI score (reflecting higher work stress) was associated with a 22-48 % elevated odds of asthma (Study 1: OR 1.48, 95 % CI 1.13-1.95, and Study 2: OR 1.22, 95 % CI 1.10-1.36). Z score-based analyses of the separate ERI components generally suggested moderate associations of effort, reward and overcommitment with asthma in both studies (Study 1: OR effort 1.25, 95 % CI 0.95-1.64, OR reward 0.67, 95 % CI 0.51-0.87, OR overcommitment 1.32, 95 % CI 1.01-1.72; and Study 2: OR effort 1.21, 95 % CI 1.09-1.34, OR reward 0.83, 95 % CI 0.76-0.92, OR overcommitment 1.12, 95 % CI 1.01-1.25). Analyses of categorized exposures largely confirmed these observations. Conclusions: This is the first study to demonstrate a link between an established work stress measure and asthma. Longitudinal studies are needed to determine the direction of these associations. [ABSTRACT FROM AUTHOR]