Asthma and chronic obstructive pulmonary disease: differences between workers with and without sick leave

Objective: Determinants of sick leave should be investigated before interventions to reduce sick leave can be designed. This cross-sectional study compares employees with asthma and chronic obstructive pulmonary disease (COPD) with and without sick leave.

Methods: One hundred and eighteen participants with asthma and 71 with COPD underwent a lung function test [one-second forced expiratory volume (FEV1), forced vital capacity (FVC)] and completed questionnaires on health complaints, work characteristics, demographic and psychosocial variables, and self-reported sick leave in the past 12 months. Backward multivariate logistic regression analyses, with sick leave (no/any) as dependent variable, were conducted for asthma, COPD, and the total group.

Results: Lung function measures were not significantly associated with sick leave in any group (P > 0.05). For asthma, psychosocial variables (spending all energy at work, OR 0.7) and health complaints (frequency of dyspnoea, OR 0.4 and breathing problems such as coughing, wheezing, OR 1.1) were associated with sick leave. In the COPD group, age (OR 0.9) was the only significant variable to be maintained in the model. In the total group, work characteristics (adjustment in work pace, OR 3.3), age (OR 0.9) and spending all energy at work (OR 0.7) were maintained in the final model.

Conclusion: Severity of the disease, as measured by lung function, is not a determinant of sick leave in asthma and COPD. Different processes play a role in asthma and COPD. Interventions for reducing sick leave should aim more at psychosocial factors than at treating the severity of the disease.