Sickness absence and flight type exposure in flight crew members

Background: Shift work research has shown that the relationship between exposure to irregular working times and sickness absence may differ between working populations. Not much is known about the prevalence of sickness absence in flight crews or about the relationship between exposure to different flight schedules and sickness absence in this population. Aims: To examine the association between cumulative exposure to different flight types and sickness absence in flight crew members. Methods: The study population consisted of flight crew members from a 5 year historic cohort. Flight schedule and sickness absence data were obtained from company records. The association between the cumulative exposure to different flight types and sickness absence episodes of >7 days was determined using univariate and multivariate logistic regression analyses. Adjusted models were obtained by adding potential confounders. Previous sickness absence was added to compose the fully adjusted models. Results: The records of 8228 employees were analysed. The fully adjusted univariate analyses showed that the numbers of medium-haul flights and flights with time zone crossings were associated with an increase in the odds for sickness absence. The fully adjusted multivariate analyses showed no significant associations between flight types and sickness absence. Conclusions: Cumulative exposure to flight types was not independently associated with sickness absence in flight crew members when previous sickness absence was taken into account. Because sickness absence in the past can predict future absence, preventive strategies targeted at flight crew members with a history of high sickness absence may be effective.