Would intervening on financial strain reduce inequalities in mental health between renters and homeowners?

Renters generally experience higher psychological distress than homeowners, which may be partially due to financial strain and difficulties to cover the costs of living. Whether interventions targeting financial strain will reduce the mental health disparities between renters and homeowners needs further investigation. We investigated the potential impact of hypothetical interventions targeting the reduction of financial strain on the observed inequality in mental health between renters and homeowners. We analysed longitudinal data from the Dutch GLOBE study (2011-2014, N = 2400). Causal mediation analysis (marginal structural model with inverse probability weighting) was employed as a methodological framework to assess how much the observed inequality in mental health between homeowners and renters would be reduced if no one would experience financial strain (estimated using the counterfactual disparity measure (CDM)) and if renters would experience the same levels of financial strain as homeowners (estimated using the interventional analogue of the natural direct effect (NDEanalogue)). Our findings revealed a substantial inequality in mental health scores between renters and homeowners, with renters exhibiting an average mental health score of 5.36 (95% CI = 4.05, 7.09) points lower on a 100-point scale. The CDM suggested that complete elimination of financial strain could lead to a 16% reduction in the observed mental health inequality between renters and homeowners (CDM = 4.51 (95% CI = 3.04, 6.56)). The NDEanalogue indicated a 14% reduction in mental health inequality under a hypothetical intervention where the distribution of financial strain among renters was set to that of the homeowners (NDE = 4.60 (95% CI = 2.75, 6.49)). Addressing financial strain may reduce the disparities in mental health outcomes associated with housing tenure.