Peer support for discharge from inpatient to community mental health care: the ENRICH research programme
Authors: Gillard Steve , Foster Rhiannon , White Sarah , Healey Andrew , Bremner Stephen , Gibson Sarah , Goldsmith Lucy , Lucock Mike , Marks Jacqueline , Morshead Rosaleen , Patel Akshaykumar , Patel Shalini , Repper Julie , Rinaldi Miles , Simpson Alan , Ussher Michael , Worner Jessica , Priebe Stefan 
Published: December 2023

Background
Rates of readmission are high following discharge from psychiatric inpatient care. Evidence suggests that transitional interventions incorporating peer support might improve outcomes. Peer support is rapidly being introduced into mental health services, typically delivered by peer workers (people with experiences of mental health problems trained to support others with similar problems). Evidence for the effectiveness of peer support remains equivocal, and the quality of randomised controlled trials to date is often poor. There is an absence of formal cost-effectiveness studies of peer support in mental health services.

Objectives
This programme aimed to develop, pilot and trial a peer support intervention to reduce readmission to inpatient psychiatric care in the year post-discharge. The programme also developed a peer support fidelity index and evaluated the impact of peer support on peer workers.

Design
Linked work packages comprised: (1) systematic review and stakeholder consensus work to develop a peer support for discharge intervention; (2) development and psychometric testing of a peer support fidelity index; (3) pilot trial; (4) individually randomised controlled trial of the intervention, including mixed methods process evaluation and economic evaluation; (5) mixed method cohort study to evaluate the impact of peer support on peer workers. The research team included: two experienced service user researchers who oversaw patient and public involvement; service user researchers employed to develop and undertake data collection and analysis; a Lived Experience Advisory Group that informed all stages of the research.

Setting
The programme took place in inpatient and community mental health services in seven mental health National Health Service trusts in England.

Participants
Participants included 590 psychiatric inpatients who had had at least one previous admission in the preceding 2 years; 32 peer workers who delivered the intervention; and 8 peer workers’ supervisors.

Intervention
Participants randomised to peer support were offered at least one session of manualised peer support for discharge prior to discharge and then approximately weekly for 4 months post-discharge.

Main outcome measures
The primary outcome for the trial was readmission (formal or informal) to psychiatric inpatient care (readmitted or not) within 1 year of discharge from the index admission. Secondary outcomes included inpatient and emergency mental health service use at 1 year post discharge, plus standardised measures of psychiatric symptom severity and psychosocial outcomes, measured at end of intervention (4 months post discharge).

Data sources
Service use data were collected from electronic patient records, standardised measures of outcome and qualitative data were collected by interview.

Review methods
We produced two systematic reviews of one-to-one peer support for adults in mental health services. The first included studies of all designs and identified components of peer support interventions; the second was restricted to randomised controlled trials and pooled data from multiple studies to conduct meta-analyses of the effects of peer support.

Results
Our systematic review indicated that one-to-one peer support improved individual recovery and empowerment but did not reduce hospitalisation. The main trial demonstrated that one-to-one peer support did not have a significant effect on readmission. There was no significant reduction in secondary service use outcomes at 1-year, or improvement in clinical or psychosocial outcomes at 4 months. Participants who received a pre-defined minimal amount of peer support were less likely to be readmitted than patients in the control group who might also have received the minimal amount if offered. Compared to care as usual, black participants in the intervention group were significantly less likely to be readmitted than patients of any other ethnicity (odds ratio 0.40, 95% confidence interval 0.17 to 0.94; p = 0.0305). The economic evaluation indicated a likelihood that peer support offered a reduction in cost in excess of £2500 per participant compared to care as usual (95% confidence interval −£21,546 to £3845). The process evaluation indicated that length and quality of first session of peer support predicted ongoing engagement, and that peer support offered a unique relationship that enables social connection. The impact study indicated that peer workers found their work rewarding and offering opportunities for personal growth but could find the work emotionally and practically challenging while expressing a need for ongoing training and career development.

Limitations
In the trial, follow-up rates at 4 months were poor, reducing confidence in some of our analyses of secondary outcome and in a wider societal perspective on our health economic evaluation.

Conclusions
One-to-one peer support for discharge from inpatient psychiatric care, offered in addition to care as usual to participants at risk of readmission, is not superior to care as usual alone in the 12 months post-discharge.

Future work
Further research is needed to optimise engagement with peer support and better understand experiences and outcomes for people from black and other ethnic communities.

Study registration
The systematic review is registered as PROSPERO CRD42015025621. The trial is registered with the ISRCTN clinical trial register, number ISRCTN 10043328.

Funding
This award was funded by the National Institute for Health and Care Research (NIHR) Programme Grants for Applied Research programme (NIHR award ref: RP-PG-1212-20019) and is published in full in Programme Grants for Applied Research; Vol. 11, No. 8. See the NIHR Funding and Awards website for further award information.