Moving out and moving on: The impact of mobility in a context of union dissolution on antidepressant intake in Belgium

Introduction: Union dissolution is a major life course transition with well-documented links to poor mental health, yet the role of post-separation residential mobility remains underexplored. Methods: This study uses linked administrative data from the Belgian Socialist Health Insurance Fund and the National Register to analyse 68,048 individuals aged 20–64 in opposite-sex partnerships in 2008 who separated between 2009 and 2018. Antidepressant use (≥90 defined daily doses/year) served as an objective indicator of treated depression. Results: Random-effects logistic regression models showed that changing municipality during or shortly after separation was not, on average, associated with higher antidepressant use than staying in the shared location. However, anticipatory effects emerged for women: those who moved during separation had higher antidepressant use before the event, suggesting pre-existing distress. Repartnering was associated with lower antidepressant use among women, particularly when combined with moving. By framing mobility as a socially embedded process shaped by gendered economic inequalities, housing market pressures, and life course dynamics, this study advances understanding of the social determinants of mental health. Discussion: Findings highlight the need for housing, welfare, and gender equity policies to support individuals during and after separation, with lessons relevant to diverse welfare state contexts.