PRESERVE HFpEF: Designing a blended lifestyle intervention to improve physical function, dietary intake, and quality of life in multi-morbid older people who have Heart Failure with preserved Ejection Fraction (HFpEF)

Background Heart Failure with preserved Ejection Fraction (HFpEF), a type of heart failure, has been described as a ‘stealth syndrome’ and ‘the greatest unmet need in cardiology.’ These labels have arisen because of the increasing number of people receiving a diagnosis and the growing body of evidence demonstrating its impact, poor prognosis, and problematic care pathways. The constellation of challenges that surround HFpEF mean that outcomes are poor, and they are projected to remain so despite emerging pharmacological therapies. Indeed, new drug treatments, which will likely lead to a resurgence in HFpEF diagnoses, should be augmented by non-pharmacological treatments that more holistically address the physical, psychological, social and environmental complexities associated with HFpEF. Modifications to diet and exercise habits have proven efficacy in mediating many of the complex negative factors linked to HFpEF. However, most research has been focussed on testing or adapting non-pharmacological interventions that have some evidence of efficacy in other forms of heart failure (salt restriction, aerobic exercise), rather than generating novel interventions that might more comprehensively address HFpEF patients’ needs. Aim The aim of this research was to conduct a programme of preparatory work that would inform the development of an evidence-based, patient attuned, multi-component or blended diet and exercise intervention in HFpEF. Methods Two systematic reviews and meta-analyses (work package 1 part 1 and work package 2 part 2) were undertaken to establish the evidence-base for diet and exercise in HFpEF. For the exercise review, the focus was on older adults with multimorbidity as the volume of primary studies in HFpEF would not allow for meaningful evaluation of alternatives to aerobic exercise modalities. These components were complemented by a qualitative secondary analysis of the HFpEF patient experience (work package 3) and patient and public involvement activities (work package 4) that explored HFpEF patients’ views on potential diet and exercise interventions. A critical appraisal of involvement activities was also undertaken to identify opportunities for enhancement of future PPI events. Learning from these components was synthesised to create a taxonomy of diet and exercise intervention components and conditions relevant to people with HFpEF (chapter eleven conclusions). Two methodological aims were addressed during the systematic review process. Firstly, an assessment of the degree of adherence that multi-component exercise interventions have to complex intervention development guidance was performed (work package 1, part 2). The impact of more robust exercise intervention development processes on functional and quality of life outcomes were evaluated in a meta-analysis of effects. Secondly, the complexity of dietary interventions in HFpEF were evaluated (work package 2 part 1) and discussed in relation to HFpEF patient characteristics. Results Work package 1 part 1 demonstrate that several exercise combinations have been tested in older adults with multimorbidity and some types of exercises, primarily aerobic, balance, flexibility, and respiratory exercises, may be more effective in improving functional and quality of life outcomes. Part 2 of this work package, demonstrate that the degree of adherence of multi-component exercise interventions to complex intervention development guidance is sub-optimal, which may lead to redundant or wasteful research. Results of a meta-analysis of effects of ‘developmentally good’ studies are also presented. Such interventions do not appear to deliver improved physical function and quality of life outcomes compared to studies that were judged as not following intervention development guidance. However, they are not inferior in terms of the effect size. Work package 2 part 1 confirms that a wide range of dietary interventions have been evaluated across multiple small studies. When these studies are combined in a meta-analysis of effects (work package 2 part 2), it would seem that some approaches are efficacious in HFpEF. For example, reducing kilocalorie and carbohydrate intake or increasing protein consumption might lead to clinically meaningful improvements in important domains like physical function, anthropometric or haemodynamic outcomes. Work package 3 describes the extent and magnitude of the impact of receiving a HFpEF diagnosis. Problems in care pathways and challenges that would need to be addressed by, or accommodated within, a future intervention to ensure its chances of success are highlighted. Patient and public involvement work described in work package 4 demonstrates that some of the intervention components identified as efficacious via systematic review are not considered appealing or feasible by the potential recipients, and thus are unlikely be implemented or adhered to in a future intervention. Progressing from consultative type involvement work to co-production methods (summarised in chapter ten), enabled valuable insights to be captured including: 1) capacity issues that might regulate or prohibit participation in a diet and exercise intervention; 2) opportunities that would need to be in place to make intervention components appealing and feasible and; 3) outcomes that would serve as motivators to participation and adherence. Systematic integration of data generated as a result of this programme has allowed for the creation of a taxonomy of potential diet and exercise intervention components and conditions for their optimal delivery (chapter eleven). This taxonomy will be the starting point for the next phase of this research which will include the co-design of a prototype invention that describes actual content and delivery methods. Conclusions This was an ambitious programme of intervention development preparatory work that has culminated in a large number of publications that individually contribute to the evidence-base. The evidence generated from this work has collectively informed the development of a taxonomy of diet and exercise intervention components and conditions that may be consolidated with other evidence and iteratively worked up into a prototype intervention. Interventions that follow robust development processes such as those described here, are postulated to have a greater chance of delivering meaningful and long lasting behaviour change. Given that behaviour change in the domains of diet and exercise are widely acknowledged to be difficult to achieve, it is important to undertake such work to enhance the chances of any new intervention being successful. This is particularly important in HFpEF where there has been limited testing of blended approaches thus far, and therefore little evidence to guide intervention development.

Name dc:type.qualificationname

Doctor of Philosophy (PhD)

Level dc:type.qualificationlevel

Doctoral

Grantor dc:publisher.institution

University of Cambridge

Year dc:date.issued

2024

Author dc:creator

• Forsyth, Faye

Advisors dc:contributor.advisor

• Deaton, Christi
• Mant, Jonathan

• Heart Failure
• Heart Failure with Preserved Ejection Fraction
• Exercise
• Diet
• Patient and Public Involvement

Licence

• https://www.repository.cam.ac.uk/bitstreams/9a09172f-3236-4c03-a6f4-9e600e3f6f38/download
• https://creativecommons.org/licenses/by/4.0/

Language dc:language

eng

DOI dc:identifier.doi

https://doi.org/10.17863/CAM.115842

OAI identifier oai:identifier

oai:www.repository.cam.ac.uk:1810/379871