The Interplay of Age and Sickness Absence: Insights from a Systematic Literature Review

Background: The likelihood of being absent from work due to a health disorder may increase in the presence of work-related psychosocial risk factors, such as high job demands, and decrease with protective factors like organizational justice. Additionally, personal characteristics, including age, can influence workers’ risk exposure and overall health. Due to the physiological aging of individuals, the aging workforce is expected to be more susceptible to work disability and, consequently, more prone to sickness absence (SA). However, there’s a lack of consensus on measuring age in SA studies. Therefore, the aim of this study is to understand better the relationship between age and SA when workers are exposed to work- related psychosocial factors. Method: This contribution is part of a larger study on SA prevention. Initially, a systematic literature review was conducted following the PRISMA Checklist to identify longitudinal studies exploring the causal relationship between work-related psychosocial factors and SA. Three online databases (i.e., PsycINFO, Medline, and Web of Science) were searched, and publications from 2012 to 2023 were included. Subsequently, a deeper analysis was undertaken to investigate how age was measured and utilized in the predictive models. Results: The systematic literature review included 31 longitudinal studies. Age in years was exclusively treated as a continuous variable in 23 studies, with the mean and standard deviation values reported in all of them. In four studies, age was solely a categorical variable, with varying age groups identified across articles. Two studies used age both continuously and categorically, depending on the statistical analyses conducted. Age information was absent in two other studies, and 11 studies did not report the age range. In the predictive models, age was mainly a covariate (n=23) with other non-work-related factors (e.g., sex) or an independent variable assessing its direct effect on SA (n=5). Three studies considered age only for descriptive purposes. Overall, older age was associated with more long-term SA. However, regarding SA frequency, some results were inconsistent in demonstrating that SA due to mental disorders was more or less likely for older workers. Conclusion: This study highlights important age measurement variation and its impact on understanding its role on SA. Consensus on age measurement is crucial. Indeed, a dedicated systematic literature review could identify whether and how age is linked to workers’ exposure to work-related psychosocial factors, which, in turn, can influence SA. From a practical perspective, these findings could help in developing organizational interventions to mitigate work-related psychosocial risk factors and promote protective ones. This, in turn, may encourage job retention among older workers and reduce annual costs associated with disabilities due to SA.