The report, which examined patients under the care of community mental health services, found incidents leading to ‘life-changing harm and death' with patients in some cases not taking their insulin as prescribed.

Nick Woodier, senior safety investigator at HSSIB, said: ‘Many of the issues we identified are long standing and persistent. Our recommendations are focused on reducing inequalities and removing barriers to care. We are calling for consistent, effective integration between diabetes and mental health services to deliver safer, more co-ordinated care and improved outcomes for people who are managing complex mental and physical health needs.

‘The investigation also identified significant concerns around access to care, including the stigmatisation of mental health within the context of diabetes care, poor recognition of type 1 diabetes and disordered eating, and repeated failures to make reasonable adjustments for patients.'

The report's recommendations, include:

• NHS England and DHSC to develop a strategy for improving collaboration between mental health teams and specialist diabetes services
• National Institute for Health and Care Research (NIHR) to map the knowledge gaps surrounding type 1 diabetes and disordered eating (including those identified in this investigation) and assess the priority and feasibility of commissioning research to help
• Royal College of Psychiatrists to develop a strategy that supports consistent recognition of patients with type 1 diabetes and evidence of disordered eating and identify associated care responsibilities for providers of mental and physical health services.

An NIHR spokesperson said: ‘As highlighted in the report, NIHR has funded an evaluation of integrated diabetes and mental health services to support patients with type 1 diabetes related disordered eating (T1DE). NIHR welcomes funding applications for research into any aspect of human health and care, including T1DE. These applications are subject to peer review and judged in open competition, with awards being made on the basis of the importance of the topic to patients and health and care services, value for money, and scientific quality.'

An RCPsych spokesperson said: ‘We welcome the Health Services Safety Investigations Body's (HSSIB) focus on the important issue of improving access to specialist care for diabetic adults with a mental illness who self-administer insulin.

‘Ensuring the safety of patients living with mental illnesses, and other complex needs, across all healthcare settings, is one of our top priorities.

‘We are reviewing the report's findings and recommendations in detail and will provide an update on our work in this area when we are invited to do so as part of the HSSIB's standard processes.'