REalist Synthesis Of non-pharmacologicaL interVEntions for antipsychotic-induced weight gain (RESOLVE) in people living with severe mental illness

Introduction

Antipsychotic medications are used to treat individuals with severe mental illness (SMI), but are associated with rapid weight gain and several physical and mental risk factors. Early, proactive weight management is necessary to pre-empt these risk factors. The aim was to understand and explain how, why, for whom, and in what contexts non-pharmacological interventions can help to manage antipsychotic-induced weight gain.

Methods

Realist review to identify contextual factors and underlying mechanisms associated with effective, non-pharmacological weight management interventions for adults > 18 years old. Practitioners and lived experience stakeholders were integral.

Results

74 documents used to construct programme theory and 12 testable context-mechanism-outcome configurations. People with SMI benefit from support when navigating interventions aimed at managing the weight gain. From a practitioner perspective, a good therapeutic relationship is important in helping people with SMI navigate early diagnosis and treatment options and facilitating exploring any pre-existing issues. Interventions that are flexible and tailored to the needs of individuals, ideally starting early in a person’s recovery journey are likely to yield better results. Additional sources of support include family, friends and peers with lived experience who can help individuals transition to autonomous goal-setting. The review findings also emphasise the significant effect of stigma/dual stigma on individuals with SMI and weight gain.

Conclusions

Successful interventions are collaborative, flexible and underpinned by early and comprehensive assessment with use of appropriate behaviour change approaches. The therapeutic relationship is key with a de-stigmatising approach required. A realist evaluation with primary data is currently underway.

Practitioner Points

• Individuals with severe mental illness on antipsychotic medications are at high risk for rapid weight gain and associated adverse mental and physical outcomes.

• Early comprehensive assessment by knowledgeable, respectful practitioners promotes therapeutic relationship development and identification of individuals’ specific risk factors and support, such as pre-existing disordered eating behaviours and the presence of family/carer and peer support.

• Case management or care coordination needs to be strengthened to ensure individuals’ access to consistent primary and secondary services, as well as community-based services.