Gender differences in the effects of economic inequality on mental conditions: a multivariate meta-analysis of Gini index and relative income position in high-income OECD countries.

BACKGROUND: Economic inequalities are established determinants of mental conditions, yet the role of gender remains insufficiently examined. In this article, we suggest that women experience a "double risk" in contexts of economic inequality: higher exposure to economic disadvantage and greater vulnerability to its mental health effects. METHODS: We conducted a two-step synthesis. First, we analyzed sex differences in relative poverty across high-income OECD countries. Mean differences were assessed using Welch t-tests, with sensitivity analyses across COVID-19 periods. Second, we performed a systematic review and multivariate random-effects meta-analysis following PRISMA guidelines. We included 21 studies reporting gender-disaggregated associations between income rank and income inequality and ICD-/DSM-based mental conditions. Effect sizes were transformed to log odds ratios and analyzed using multilevel models accounting for within-study dependencies. Gender was examined as a moderator. RESULTS: Women exhibited higher relative poverty rates than men (20.5% vs. 18.3%; mean difference: 2.2 percentage points; p < 0.001). The meta-analysis (46 effect sizes) showed a significant association between lower income and poorer mental health (log(OR)=0.55, 95% CI 0.26-0.85), with substantial heterogeneity. Gender did not moderate effects across all outcomes. However, in depression-specific analyses (k=17), gender significantly moderated the association (p=0.016), with stronger effects in women. Income inequality (Gini index) showed no overall association with mental health, but gender still emerged as a significant moderator, with effects concentrated among women in adjusted models. CONCLUSIONS: Gender shapes both exposure to economic disadvantage and vulnerability to its mental health consequences. While income-related mental health inequalities affect both sexes, women appear disproportionately impacted, particularly regarding depression. These findings highlight the importance of integrating gender-sensitive approaches into research and policy addressing socioeconomic determinants of mental health. SYSTEMATIC REVIEW REGISTRATION: https://www.crd.york.ac.uk/PROSPERO/view/CRD420251123692, identifier CRD420251123692.