General discussion

We used a multi-methods approach across three research WSs with the goals to better understand the psychological needs and preferences for psychological therapy in CR patients with anxiety and depression symptoms, and to conduct two separate randomised feasibility trials followed by two full-scale RCTs of MCT.

We were able to meet almost all our study objectives as outlined under the primary funded proposal. However, we did not complete a preliminary cost-effectiveness analysis around the home-based intervention. Nevertheless, we did accomplish a full-scale RCT extension of the home-based intervention (WS3) under the same VTC.

We found both Group-MCT and Home-MCT to be feasible and acceptable treatments to deliver and evaluate within CR, and both treatments were associated with better overall depression and anxiety at 4 months. Group-MCT was also evaluated at 12 months, at which point outcomes remained improved compared with CR alone. However, the long-term impact of Home-MCT remains to be evaluated.

Challenges and limitations

A number of challenges were faced throughout the grant, and below we summarise the main challenges and limitations.

The studies reported here did not include a comparison or control group involving the addition of an alternative psychological treatment to CR. We are therefore unable to attribute the improved outcomes in the MCT conditions to the effect of MCT solely, rather than to the provision of extra support and contact time this entailed. As previous trials in mental health have demonstrated that MCT can produce superior outcomes to other psychological treatments in anxiety and depression,13 we chose a more pragmatic research question here: can we improve outcomes when we add MCT to CR?

One of the main challenges faced in WS1 and WS2 was the delivery of MCT by CR staff who had no previous training in mental health treatment. During the feasibility study,14 it was not possible to assess the quality of therapy delivered because of limitations of obtaining consent for audio-recording the sessions. As a result, we were reliant on staff feedback on challenges they encountered during Group-MCT delivery. As the treatment was delivered by CR staff who are not mental health specialists, this may mean that Group-MCT was not delivered optimally. To understand the delivery of MCT further, we interviewed patients to assess their understanding and experience of Group-MCT.22 Despite therapists receiving limited training in MCT, patients did understand the aims of MCT and its techniques and found the therapy beneficial. However, we were unable to gain a thorough understanding of why some patients did not complete Group-MCT, as only four patients who withdrew from Group-MCT were interviewed. This is an important consideration for any future roll-out of Group-MCT and could provide information to support the transferability of MCT across the CR context.

The study did not include a measure specific to quality of life, and further research should explore the relationship between anxiety and depression outcomes and broader quality of life in the CR population.

In the economic evaluation components, the key challenges and limitations concerned the availability of data. For WS3+ in particular, the inability to access service use data to support costing because of information and technology requirements, as well as time frame and budget constraints, prevented an economic evaluation. For WS2, the economic evaluation was also affected by the sample size and large amount of missing data.

In the stated preference survey,26 one of the limitations was sample recruitment as the sample size for the study was limited and lacked diversity. The sample that responded to the survey was homogeneous, with most respondents being male, over the age of 55 years and retired. This limited the ability to investigate which patient characteristics were tied to delivery preferences. Recruitment for the stated preference survey occurred during the COVID-19 pandemic, which may have influenced the response rate and the responses, which in turn limits generalisability. We discussed the results with our PPI group, who noted that patient preference indicated in the survey may have been affected by local and national lockdown restrictions, which might have strengthened preferences for home-based interventions.

Implications for practice

Improving psychological support within cardiac services is imperative, as elevated anxiety and depression in CVD patients is associated with increased mortality and morbidity, poorer quality of life, greater social problems and higher healthcare costs. The PATHWAY programme has demonstrated that adding Group-MCT to CR was associated with significantly improved anxiety and depression and a wider range of psychological gains that could be sustained over 12 months. Furthermore, a home-based version of MCT when added to CR was also related to improved outcomes when assessed over 4 months. The effect sizes of treatment compare favourably with those of previous studies of psychological interventions, and the treatments could potentially be delivered by CR staff with minimal additional training.

The implications for clinical practice can be summarised as follows:

1. Evidence of positive outcomes associated with a recent psychological treatment (MCT) when used in the context of CR
2. Greater integration of physical and mental health care in heart disease
3. Two formats of psychological treatment (group based and home based) that contribute towards a menu-based approach to CR that is sensitive to patient needs and improves access
4. A better understanding of the mental health needs of CR patients and their preferences for psychological intervention delivery in the NHS that will support service planning, evaluation and research
5. Manualised interventions that could potentially be incorporated in routine CR as a first-line approach for patients with anxiety/depression, with more complex specialist delivered mental health interventions offered to non-responders or those requiring additional help

The results of qualitative analysis coupled with trial outcomes on primary and secondary (psychological mechanism) variables are supportive of MCT as particularly well suited to CVD in comparison with other treatments. It may offer improvements over interventions that target reality-testing of thoughts and relaxation as it offers a good fit with patients’ needs and experiences. The results add to the growing body of studies suggesting that MCT, which targets metacognitions may be suited to alleviating anxiety and depression in patients with a range of physical health conditions.22,23,31,32

If used in practice, the expectation would be that MCT should be adopted as an option in the National Audit of Cardiac Rehabilitation database so that its use can continue to be assessed. Further training and supervision in the delivery of MCT would be required.

Recommendations for future research

There are a wide range of recommendations for future research that stem from the current series of studies. The relative effects of MCT in comparison with other therapies or additional contact time remains a major question for future research to examine. Further important recommendations in order of priority are summarised as follows:

1. To help realise the clinical potential of MCT in CR, future research should examine its implementation in the NHS and examine the barriers to and enablers of its adoption and roll-out across CR services.
2. Evaluation of the longer-term (12-month) follow-up effects associated with home-based MCT is recommended and should be undertaken as a matter of priority.
3. Health-economic impacts of the inclusion of MCT in CR should be part of future large-scale evaluations. Further research should aim to reduce the uncertainty in the findings for Group-MCT related to cost-effectiveness, for example with larger sample sizes. Additional research exploring how cost-effectiveness differs according to the implementation of MCT within CR and how cost-effectiveness differs by setting would be useful for decision-makers in other settings. Finally, an economic evaluation to establish the cost-effectiveness of Home-MCT is needed.
4. Our stated preference studies demonstrated that there is likely to be heterogeneity across populations with respect to their preferences for the delivery of psychological therapy in CR. Further research with larger and more varied samples should assess how preferences differ by group.
5. We were able to interview only a small number of patients who did not complete treatment and future research is required to examine the reasons that patients drop out of therapy.
6. Given that MCT is based on a model of specific causal psychological mechanisms that are directly targeted in treatment, mechanism-focused research is clearly indicated. Such research can test mechanisms of anxiety and depression and mechanisms of recovery, helping to refine and strengthen interventions.

Conclusions

The data suggest that currently the psychological needs of patients in CR are not being met, as evidenced by the rates of anxiety and depression among this group, by the lack of standard provision of psychological therapy and by the results of our qualitative studies on patient needs and preferences for therapy. An analysis of psychological needs appeared to fit the objectives of MCT better than the objectives of cognitive–behavioural approaches. Moreover, CR patients did not particularly value current techniques such as relaxation methods used in CR.

We found that both Group-MCT and Home-MCT were feasible and acceptable treatments to deliver and evaluate within CR for the treatment of anxiety and depression. Both treatments were associated with significant reductions in overall depression and anxiety symptoms at 4 months when added to CR that exceeded the effects observed with usual CR alone. Group-MCT was also evaluated at 12 months, at which point anxiety and depression outcomes remained better than with usual CR alone. The long-term impact of Home-MCT remains to be evaluated. The economic evaluation suggests that Group-MCT may be a cost-effective treatment to deliver within CR. However, sample size, missing data and variability in the data led to considerable uncertainty about the cost-effectiveness.

The DCEs demonstrate that participants (including the general public and trial participants) would value making psychological treatment available. For face-to-face therapy there was a preference for individual treatment, while people appear to favour online/smartphone-assisted therapy for home-based therapy, but this was not significant and might have been impacted by the COVID-19 pandemic restrictions.

It is important to highlight the context of this research programme, namely that the chief investigator (AW) is the originator of MCT and the director of the Metacognitive Therapy Institute. He has received funding as chief investigator on the subsequent study ‘Implementing Group Metacognitive Therapy in Cardiac Rehabilitation Services (PATHWAY-Beacons; NIHR29567)’ and is chief investigator on the projects NIHR201495 and NIHR35997 and also co-chief investigator on NIHR203634. Steps were taken throughout the research programme to maintain objectivity; these have been highlighted in this report and included the masking of patient treatment allocation from Adrian Wells, the trial statistician and the research assistants, data being managed by a separate clinical trials unit, data analysis following a prespecified plan and project monitoring and support being provided by an independent TSC.

In conclusion, MCT appeared to be an acceptable addition to CR that fit well with patients’ underlying needs in addressing symptoms of depression and anxiety. MCT was associated with improved psychological outcomes, with the implication that it could contribute to effective treatment offered in CR services within the NHS.