The range of countermeasures to reduce inequalities in mental health care for socially marginalized or medically vulnerable adults: a PRISMA systematic review.

backgroundSocially marginalized or medically vulnerable adults are affected by severe health inequalities and are at increased risk of poorer accessibility and quality of integrated mental health care. This study aimed to identify groups of socially marginalized or medically vulnerable adults and to collect the already implemented or proposed countermeasures to reduce inequalities in high-quality integrated mental health care for such individuals with mental health disorders.

methodsA systematic literature review was conducted according to PRISMA guidelines in Web of Science, CINAHL, and PubMed, covering 2014–2023. Studies on integrated mental health care for socially marginalized (SM) or medically vulnerable (MV) adults were included; those unrelated or targeting children/adolescents were excluded. Risk of bias was considered qualitatively, without formal assessment. Results were synthesized narratively and presented in structured tables, grouping interventions by predefined SM and MV categories.

resultsThis research, based on the 79 studies included in the review, identifies gaps in access to services, gaps in the quality and integration of care, and gaps in tailored interventions for SM/MV adults. A spectrum of countermeasures to reduce inequalities for quality integrated mental health care for SM or MV adults was compiled. The countermeasures need to be addressed comprehensively as part of integrated mental health and social care for SM or MV people and promote culturally competent ethical attitudes among health professionals and in society at large. By synthesizing classifications from existing frameworks and literature, we identified 18 SM/MV groups associated with poor access and quality in mental health care. Given the overlapping and cumulative nature of risk factors, SM and MV categories were analyzed collectively rather than separately. DISCUSSION: The countermeasures identified are largely transferable across SM/MV groups, with only minor adaptations needed for specific contexts. They address not only stigma but also structural, organizational, and interpersonal barriers to high-quality integrated mental health care, providing a foundation for comprehensive, equity-focused interventions. Nevertheless, findings should be interpreted with caution due to heterogeneity among studies and the absence of formal certainty assessment.