Title: Developing and evaluating a diabetes self-management intervention for people with severe mental illness: The DIAMONDS programme (Diabetes and Mental Illness, Improving Outcomes and Self-management)
Funder: Department of Health and Social Care

Abstract: Aims: We will develop and evaluate a diabetes self-management intervention for people with severe mental illness and type 2 diabetes, and explore the generalisability of our approach to other comorbid long-term physical health conditions. Objectives: Identify factors that promote or inhibit self-management behaviours in people with severe mental illness and comorbid long-term conditions. Design self-management interventions for diabetes and for chronic obstructive pulmonary disease (COPD) that address these factors, and refine their design through iterative testing. Optimise the design of the diabetes self-management intervention and trial design. Determine clinical and cost-effectiveness of the diabetes self-management intervention. Estimate its longer-term cost-effectiveness. Develop a framework for adapting self-management interventions for other long-term conditions in severe mental illness. Background: People with severe mental illness experience higher rates of physical illness and a shorter life expectancy by 15-20 years. Diabetes contributes significantly to this health inequality, being 2-3 times more common and having poorer outcomes in severe mental illness compared with the general population. Self-management is the cornerstone of good diabetes care. Diabetes self-management programmes are effective in improving clinical outcomes and reducing healthcare costs, and are recommended for all individuals with diabetes in the UK. However, existing programmes do not address the additional cognitive, motivational, lifestyle and socio-economic challenges faced by people with mental illness. As self-management programmes are rolled out in the UK, tailored programmes for people with co-existing mental illness are required to avoid a widening of already prevalent health inequalities. Research plan: Following the Medical Research Council framework for design and evaluation of complex interventions, and drawing on our NIHR Programme Development Grant work, this programme comprises six complementary work-streams: Work-stream 1: A narrative synthesis of the literature and a qualitative study involving individual interviews with patients (n=35), and focus groups with carers (n=18) and with healthcare staff (n=18) will help identify potentially modifiable factors that promote or inhibit self-management in people with severe mental illness alongside any long-term physical condition. Work-stream 2: Informed by findings from work-stream 1 and our previous work, expert consensus will be used to select intervention targets and behaviour change techniques that can modify these determinants, to include in tailored diabetes and COPD self-management interventions. We will co-design both of these interventions with patients, carers and healthcare staff (n=15), and develop digital applications, as deemed appropriate, to support them. We will iteratively test intervention components with patients (n=15-20) to optimise their potential acceptability and efficacy. Work-stream 3: We will assess acceptability and feasibility of delivering the diabetes self-management intervention (which we are calling DIAMONDS), and of evaluating it in a trial. Thirty-two participants with severe mental illness and type 2 diabetes will be recruited from two mental health trusts and 10 general practices and randomised (1.2:1 ratio) to receive the DIAMONDS intervention or usual care in a feasibility trial. We will collect data for our planned outcome measures and monitor intervention adherence. Thematic analysis of semi-structured interviews with patients (n=19), carers (n=9) and healthcare staff (n=10) will identify ways to optimise the intervention and trial design, and inform development of a training package for staff delivering the intervention. Work-stream 4: In a multi-centre randomised controlled trial (including an internal pilot) of 446 participants from 10 mental health trusts and 60 general practices randomised (1.2:1 ratio), we will test effectiveness of DIAMONDS compared to usual care (offer of a generic diabetes self-management intervention). The primary outcome will be HbA1c at 6 months; secondary outcomes will include HbA1c at 12 months, and self-management activities, mental and physical health, and quality of life at 6 and 12-months. A process evaluation will explore variation in uptake and implementation using thematic analysis of semi-structured individual interviews with patients (n=20-25) and carers (n=10-15), and five focus groups with healthcare staff (n=30). Intervention fidelity will be assessed using a pre-developed framework. A cost utility analysis will assess cost-effectiveness at 6 and 12-months. Work-stream 5: We will develop an economic model bringing together evidence from secondary data analysis of longitudinal patient-level records, focused literature reviews and the trial to estimate long-term cost-effectiveness of the intervention. Work-stream 6: We will synthesise findings from the programme (including learning from development of both interventions) and conduct multi-stakeholder workshops to develop a framework for adapting self-management interventions for people with severe mental illness and other long-term conditions. Dissemination and impact: If the diabetes self-management programme is shown to be worthwhile, we will develop a detailed plan for its implementation and uptake in the NHS. We will disseminate programme outputs to all likely beneficiaries of our research, working closely with a wide range of stakeholders. This research will have the potential to improve self-management and outcomes for people with severe mental illness and diabetes, and for those living with other comorbid long-term conditions, helping to reduce healthcare costs and health inequalities.

Lay abstract: Aim: To develop and test a self-management programme for people with severe mental illness (SMI) and type-2 diabetes; and to explore its relevance to people with SMI and other chronic physical health conditions. Background: SMI refers to conditions such as schizophrenia and bipolar disorder, which cause considerable disability over a lifetime, and affect 1% of the population. People with SMI are at high risk of developing long-term physical health problems. For example, they are almost three times more likely to have diabetes and have higher rates of other long-term illnesses, such as chronic lung disease. The impact of diabetes is influenced by how well it is managed. Self-management (activities which people do to manage their illness) is at the heart of good diabetes care; it can improve physical and mental health, and reduce healthcare costs. However, people with SMI are unlikely to benefit from existing self-management programmes because they face additional challenges to managing their health that currently available programmes do not tackle. Research plan: We will design and test a self-management programme for people with SMI and type-2 diabetes (DIAMONDS). We will also explore how relevant this approach might be to other long-term conditions, by also designing a programme for people with chronic lung disease, which has many aspects of self-management in common with diabetes, but also elements that are very different. The research programme comprises six complementary studies: 1. We will first learn what helps and does not help people with SMI to manage any chronic physical health condition by reviewing the literature and interviewing patients, carers and healthcare staff. 2. We will use this information to design two programmes&ndash; one for diabetes (DIAMONDS), and one for chronic lung disease, using workshops where patients and healthcare professionals jointly design, test and refine the programmes. Technology experts will help develop mobile phone or Internet-based materials as appropriate. 3. We will test DIAMONDS in a small-scale study to test whether it is acceptable and can be delivered. 4. We will conduct a large trial to test whether DIAMONDS improves glucose control and physical and mental health. Trials are experiments where people are split into two (or sometimes more) groups by chance. One group is given the new experimental treatment and the other group is not. 5. We will estimate costs and long-term benefits of DIAMONDS. 6. We will draw together learning from developing DIAMONDS and the chronic lung disease programme to explore how our approach can be adapted for people with SMI and other long-term conditions. Dissemination: We will develop plans for future roll-out of DIAMONDS to NHS patients. Service users and carers will be involved in all stages, including communication of results to public, patient, healthcare and research audiences.

Research activity codes: 7.1 INDIVIDUAL CARE NEEDS
Health categories: MENTAL HEALTH;METABOLIC AND ENDOCRINE