Dual trajectories of short-term and long-term sickness absence and their social- and health-related determinants among women in the public sector.

Background: Short- and long-term sickness absence (SA) vary in their determinants. We examined short- and long-term SA contemporaneously as two interconnected phenomena to characterize their temporal development, and to identify employees with increasing SA at an early stage.

Methods: We extracted 46- to 55-year-old employed women from the Helsinki Health Study occupational cohort during 2000-17 (N = 3206) and examined the development of short- (1-14 days) and long-term (>14 days) SA using group-based dual trajectory modelling. In addition, we investigated the associations of social-, work- and health-related factors with trajectory group membership.

Results: For short-term SA, we selected a three-group solution: 'no short-term SA' (50%), 'low frequency short-term SA' (40%), and 'high frequency short-term SA' (10%) (7 spells/year). For long-term SA, we also selected three trajectory groups: 'no long-term SA' (65%), 'low long-term SA' (27%), and 'high long-term SA' (8%). No SA in the short-term SA model, indicated a high probability of no SA in the long-term model and vice versa. The developmental pattern was far less certain if participant was assigned to a trajectory of high SA in either one of the models (short- or long-term SA model). Low occupational class and poor health behaviours were associated with the trajectory groups with more SA.

Conclusion: SA does not increase with age among most employees. If either SA rate was high, the developmental patterns were heterogenous. Employers' attention to health behaviours might aid in reducing both short- and long-term SA.