ABSTRACT:
People living with psychosis experience disproportionately high levels of loneliness1, yet there is currently a lack of interventions specifically tailored to their needs2. Existing approaches often focus on individual-level change, overlooking the broader social, interpersonal, and structural factors that compound disconnection. Given the complex and intersecting drivers of loneliness in this population, including stigma, marginalisation, and reduced access to meaningful social roles3, addressing loneliness is not only a mental health concern but also a matter of health equity and social inclusion. A more nuanced understanding is essential to inform effective, scalable public health strategies. We conducted a rapid realist review4 to explore how, why, and in what contexts interventions may reduce loneliness in people with psychosis. The review synthesises findings from 50 peer-reviewed papers and is enriched by consultations with academic and clinical experts as well as lived experience advisors. Context–Mechanism–Outcome (CMO) configurations were developed to build a theory-driven framework of effective intervention strategies. The review identified a broad range of potential intervention targets at the individual (e.g. self-esteem, internalised stigma), interpersonal (e.g. relationship quality), community (e.g. social integration), and structural (e.g. housing) levels. For each target, we suggest possible intervention strategies grounded in theory and evidence. Findings highlight the importance of intersectionality and support the development of personalised, co-produced, multi-level approaches that are responsive to the lived realities of people with psychosis. Although most evidence comes from high-income countries, these principles are applicable across diverse settings and provide actionable insights to design interventions and public health policies that reduce loneliness, promote inclusion, and advance health equity in this underserved population.