Organization leaders' decisions to sustain a peer-led healthy lifestyle intervention for people with serious mental illness in supportive housing.

Healthy lifestyle interventions that increase physical activity and healthy dietary habits can help improve the physical health of people with serious mental illness (SMI). Yet, these interventions are not implemented in routine practice settings. This mixed methods study examined the decisions that leaders from three supportive housing agencies made as they planned to sustain a peer-led healthy lifestyle intervention for people with SMI at the end of a clinical trial. A combination of implementation strategies that addressed cost concerns, generated local evidence of the intervention's benefits, and provided ongoing training was identified as important for sustainability. A sustainability model illustrating implementation strategies and mechanisms for supporting three sustainability domains (funding, organizational capacity, and adaptation) was prioritized by participants. Study findings can inform future studies testing strategies and mechanisms to support the sustainability of interventions in routine practice settings to improve the physical health of people with SMI.