Understanding prevalence and impact of frailty in chronic illness and implications for clinical management

People who are more likely to become seriously unwell following relatively minor events (e.g. infections) are said to have "frailty". Frail people are more susceptible to harms, for example, from having diagnostic tests or side-effects of medications. Compared to people without frailty, this makes it harder to deliver the best care.

Although older people are more likely to be frail, not all older people are frail. Younger people can also be affected by frailty, especially those with chronic illness such as diabetes. However, there is very little evidence about how clinical management should be adjusted in people with frailty, particularly younger people.

A major gap in evidence relates to clinical trials. Clinical trials are the most important source of evidence about the effectiveness of treatments (e.g. a particular drug). It is generally believed that frail people are less likely to be included in trials. However, since trials do not usually measure frailty we do not currently know how often frail people are included, or if frail trial participants are similar to people in the community with frailty. This leaves clinicians uncertain about whether they can use the evidence from trials when deciding which treatments to offer frail people.

A second challenge in managing frailty concerns "self-management", which is something everyone who has a chronic illness needs to learn. Self-management involves people balancing their condition (e.g. diagnostic tests, attending appointments, accepting treatments) against other priorities in their lives, given their own capacity and resources (e.g. financial circumstances, social support, other commitments). It is likely that self-management is more difficult for frail people. However, no previous study has reviewed all the published research to see if and how the presence of frailty should change the way health professionals support self-management.

We plan to address both evidence-gaps.

Aim

To identify and measure frailty in clinical trials, as well as in community settings, to assess how best to apply evidence from trials when deciding what treatments to offer people with frailty and chronic illness. Secondly, we will undertake a detailed review of published research to determine how to support self-management in the presence of frailty.

As examples, we will study data from people with three important and common long-term conditions: type 2 diabetes, rheumatoid arthritis, and chronic obstructive pulmonary disease

Objectives

For type 2 diabetes, rheumatoid arthritis, and chronic obstructive pulmonary disease:

1. To estimate how common frailty is, in both the community and in participants in clinical trials

2. To examine the relationship between frailty and deteriorating health (e.g. increasing breathlessness, increased hospitalisation), for both community and clinical trial settings

3. To assess whether the effectiveness of drug treatments is different for people with and without frailty

And for type 2 diabetes

4. To review published research on self-management, to determine how best to account for a person's frailty, level of function, and wider social support when supporting self-management.

Potential applications and benefits

This work will improve understanding of the consequences of frailty. It will also develop and test methods for identifying frailty within trials. This will provide insights into how existing evidence applies to frail people.

This project will therefore benefit people with frailty, clinicians, guideline developers, healthcare organisations and health policymakers to understand the implications of frailty and how to best treat people with frailty, and support them to manage their health.

It will also guide the design of future research by determining the extent to which current research (e.g. clinical trials of drugs or self-management approaches) includes people with frailty.

Technical Summary

Aim

To assess the prevalence and importance of frailty using three exemplar non-communicable diseases (NCDs) (type 2 diabetes, rheumatoid arthritis and chronic obstructive pulmonary disease), and to explore implications of frailty for management.

Objectives

-Assess the prevalence of frailty, by age and sex, in each exemplar NCD, comparing general population estimates to participants in randomised controlled trials

-Examine the association between frailty and clinical outcomes

-Explore if the efficacy of drug treatments differs by frailty status

-Assess how self-management should be supported in frail people

Methods

Data will be drawn from large population cohorts as well as individual patient data from phase 3/4 randomised controlled trials. Frailty will be quantified using a frailty index (in trials and population cohorts) and frailty phenotype (cohorts only). The prevalence and degree of frailty in trial populations will be compared to population estimates accounting for age, sex, and clustering inherent in the data. The relationship between frailty and clinical outcomes will be assessed. Where frailty is present in clinical trials, the impact on adverse event rates and relative treatment effectiveness will be analysed using interaction terms.

A systematic review of self-management interventions for type 2 diabetes will explore if interventions account for frailty or functional status, and to what extent this affects outcomes.

Scientific/medical opportunities

Frailty has not previously been studied in clinical trial settings for these conditions. The proposed work will help us better understand prevalence and implications of frailty and also assess the extent to which existing evidence takes account of frailty in target populations. Where frailty is identified, this work will inform the application of clinical evidence to this population. This will allow more accurate estimation of potential risks and benefits and tailoring of interventions.