Predictors of changes in sick leave in workers with asthma: a follow-up study.

Objective: The aim of this prospective study was to investigate predictors of 1-year changes in sick leave in workers with asthma.

Methods: The initial cohort consisted of 111 workers with asthma. One-hundred and one participants completed the follow-up after 1 year. Self-reported sick leave over the past 12 months was reported at baseline and at follow-up. At the start of this study, all participants completed questionnaires on adaptation to functional limitations, psychosocial variables, working conditions, lung function characteristics, disease history characteristics, health complaints and functional limitations, and person characteristics ('potential predictors'). Three multivariate logistic regression models were calculated, with an increase in sick leave, a decrease in sick leave, and stable high sick leave as dependent (outcome) variables, and the potential predictors as independent (explanatory) variables.

Results: An increase in sick leave was predicted by a lower level of education and perceiving more functional limitations in activities of daily life. A decrease in sick leave was predicted by spending all energy at work less often and perceiving fewer health complaints in social activities (adaptation criteria 4 and 5). Stable high sick leave was predicted by less job satisfaction, perceiving more support from the employer and perceiving more health complaints in social activities (adaptation criterion 5). Lung function characteristics, or disease history characteristics were not predictive for changes in sick leave in any of the groups.

Conclusion: We conclude that adaptation to functional limitations played a major role in changes in sick leave in workers with asthma. Lung function characteristics hardly played a role.