NIHR Strategic Framework for Multiple Long-Term Conditions

The NIHR Strategic Framework for Multiple Long-term Conditions Research Refresh

This document sets out what the NIHR means by the term ‘multiple long-term conditions’ (MLTC) and summarises priority areas for future research. The NIHR intends to create a common understanding across the MLTC research community and encourage research activities which address the areas set out in the Strategic Framework below. The Framework sets out the NIHR’s aims to improve the lives of people with MLTC and their carers, and provide the evidence needed to address challenges in managing MLTC within health and social care services. The framework has been informed by the NIHR MLTC Oversight Group, as well as by meetings with researchers from across the UK.

Since this framework was first published in 2020, the NIHR has made great progress in working towards the ambitions set out below. Our 2021 evidence collection highlights recent research from the NIHR and other funders on risk factors for MLTC, disease clusters, prevention strategies and the impact of MLTC on people and health and care services, and our 2023 evidence collection explores more recent NIHR-funded research on the intersection of MLTC and health inequalities and how we can address the challenges. The NIHR continues work to promote and enable MLTC research across the NIHR, such as through the launch of the new MLTC Cross-NIHR Collaboration to bring together MLTC researchers across the NIHR’s translational, applied and policy research infrastructure to build MLTC research capacity, capability and leadership.  

In this refreshed strategic framework, we refine our preferred terminology for MLTC and reiterate our priorities for research in this area, with an increased focus on addressing inequalities in the development and experiences of MLTC. 

Evolving Terminology: From MLTC-M to MLTC

The preferred terminology of MLTC has evolved over time. Previously the terms ‘comorbidity’ and ‘multimorbidity’ were routinely used by researchers and clinicians to describe a person with more than one long-term condition, and the NIHR used the combined term of ‘multiple long-term conditions – multimorbidity’ or ‘MLTC-M’. However, many patients and members of the public don’t understand or like the terms ‘comorbidity’  or ‘multimorbidity’, and in recent years the term ‘MLTC’ has become significantly more embedded in NIHR culture and the wider research community. Therefore, the NIHR is moving from use of the term MLTC-M to MLTC, although the definition of MLTC (see below) remains the same. 

The NIHR defines ‘multiple long-term conditions’ as the existence of two or more long-term conditions, each one of which is either: 

• A physical non-communicable disease of long duration, such as a cardiovascular disease or cancer
• A mental health condition of long duration, such as a mood disorder or dementia
• An infectious disease of long duration, such as HIV or hepatitis C. (Academy of Medical Sciences)

There are some people who do not fit into the above definition but have similar experiences to people with MLTC, such as when navigating the health and social care system. These challenges are relevant to people with a single condition which affects multiple systems within the body, and who are therefore brought into contact with a range of services led and managed by different parts of the health and care system. Examples of this include children with Cerebral Palsy who have motor problems, visual impairment and learning difficulties.  The complexity brought about by navigating such conditions could be described as Complex Care Needs. NIHR would consider this patient/carer group eligible to be included in research covering MLTC if aligned with the aims set out in our strategic framework. 

Research commissioned within the NIHR MLTC strategic framework will be inclusive of conditions, in that it includes physical and mental health conditions, and single conditions which result in multisystem impacts or functional loss. The term employed in a particular project or programme will depend on the primary research objective and the problem the research is attempting to solve. Panels will assess applications to ensure that the research commissioned under the MLTC strategic framework is aligned with the aims set out in the MLTC strategic framework. The NIHR are particularly interested in combinations of conditions that are especially burdensome for patients, patients’ families and carers, and the health and care system, however, research into two conditions would still be included within the MLTCs theme.

The NIHR Strategic Framework for Multiple Long-term Conditions Research

The NIHR Strategic Framework for Multiple Long-Term Conditions Research was first published in April 2020 and encompasses the NIHR’s ambition to promote and enable research into MLTC. It aims to improve the lives of people with MLTC and their carers, and provide the evidence needed to address challenges in managing MLTC within health and social care services. The high-level aims set out below provide a shared focus for the NIHR to promote and enable high-quality MLTC research in its mission to improve the health and wealth of the nation. 

Addressing Key Evidence Gaps

The NIHR will fund high quality research to provide an evidence base which:

1. Identifies and maps common clusters of disease and their trajectories among the population
2. Identifies the problems and outcomes that matter most to patients and carers and how they would like to see services configured to meet their needs
3. Delivers research into models of care that enable the health and social care system to take a person-centred approach to the treatment and care for people with MLTC, including quality of life and well-being
4. Supports design and delivery of interventions to prevent patients progressing from one long-term condition to MLTC
5. Addresses[1] the inequalities that drive and exacerbate MLTCs, in particular amongst disadvantaged communities and regions which have historically been under-served by health and social care research
6. Develops methodologies suitable to MTLC research. This includes developing definitions that can be used across studies, developing appropriate outcome measures that capture outcomes that matter to people with MTLC and developing robust methodologies to address the complexity of MLTC

[1] Since the framework was published in 2020, considerable progress has been made in the MLTC research field. In May 2023 the Multiple Long-term Conditions Oversight Group (MOG) agreed that, a refresh of the framework would be useful to incorporate greater emphasis on a number of key areas. Following the refresh, points 5 and 6 were added to the framework.

Fostering a Change in NIHR Culture and Practices

The NIHR will:

• foster a change in NIHR culture and practices to promote and enable more and higher quality research into MLTC
• promote a common terminology around MLTC that makes sense to funders, researchers, practitioners, patients and the public
• engage with, and beyond, the NIHR community to provide and raise awareness of opportunities to move into research on MLTC or acknowledge or include an MLTC lens explicitly in research projects;
• engage with delivery and implementation colleagues (e.g. NHS, Social Care, Local Authorities) and regulators to support research translation into practice
• review and adapt our funding processes (engagement, application, panel) to support applications in MLTC research
• foster a multi-disciplinary workforce through a new generation of researchers working beyond usual single disease specialisms
• work with other stakeholders to consider the clinical education and workforce training that will be needed to support the delivery of MLTC research and implementation of findings
• support and enable MLTC research across different research disciplines and career stages
• work with stakeholders to increase the visibility of NIHR training and development opportunities available through the NIHR Academy
• ensure that research does not unjustifiably exclude people with MLTCs, by working with the research community to understand barriers to recruitment and making it easier for people with MLTCs to participate by ensuring that studies are designed inclusively
• encourage the definition and consistent collection of outcome measures relevant to MLTC, and facilitate more appropriate monitoring of research with an MLTC component

A Person-Centred Approach to MLTC Research: areas of particular focus

While MLTC encompasses a range of different combinations of conditions, and considerable diversity in the circumstances of people living with multiple conditions, there are patterns of similar experiences. The NIHR takes a life-course approach to MLTC and is committed to tackling the stark inequalities seen in the development and experience of living with multiple conditions. 

Historically MLTC research has focused on older populations and has at times been confused with frailty. But the median age at which people are acquiring multiple conditions is falling, and now almost 20% of 25–64-year-olds have more than one condition. Research funding into MLTC and associated needs will apply to populations at all stages of the life-course, unless stated otherwise, and we would like the research community to address this need. 

The burden of MLTC has enormous implications for people’s lives, their families, the economy and for the future of the health and care system, regardless of geography or demographic. However, people within disadvantaged communities or of lower-socioeconomic status are disproportionately living with numerous and often complex health problems - exacerbated by higher rates of many lifestyle risk factors - and are more likely to develop MLTC earlier in life. Certain periods of life, such as pregnancy, also increase the likelihood that multiple conditions present concurrently. Environmental risk factors may also come into play though there is currently a limited evidence base that explores links to MLTC. We therefore expect that all MLTC research commissioned through NIHR takes a biopsychosocial approach that considers wider determinants such as socioeconomic, cultural, and environmental factors as appropriate. 

The burden of MLTC should be considered in research to ensure that we are doing the research with the populations most in need. We’d like research to consider people who are living with MLTC where the burden of their multiple conditions is more than the sum of its parts. 

Addressing the complexities and challenges of MLTC across the health and care system will require cross-disciplinary research across different settings and communities. 

Supporting the delivery of the Strategic Framework

Delivery of the Strategic Framework is overseen by the MLTC Oversight Group (MOG). The MOG’s role includes: 

• providing advice to help prioritise activities, identifying key areas of interest and providing oversight of the implementation plan for NIHR activity in MLTC
• providing a reporting mechanism, scrutiny and assurance for the work being delivered across the NIHR coordinating centres, and through the NIHR MLTC Cross-NIHR Collaboration
• ensuring that NIHR communications are cohesive and internally consistent at the national level, raising the profile of the NIHR’s work in supporting MLTC research to demonstrate leadership in this area
• ensuring activities align with other relevant NIHR strategic priorities
• identifying opportunities and intelligence, including international initiatives, relevant to the NIHR

Find out more about MLTC research across NIHR, MLTC as a strategic priority and how you can get involved in MLTC research and further detail on the MLTC Cross-NIHR Collaboration.