Synopsis

Background

Cardiovascular disease and cardiac rehabilitation

Cardiovascular diseases (CVDs) are associated with approximately 25% (168,000) of all deaths each year in the UK. Survival rates are improving, with an estimated 7.64 million people in the UK living with heart or circulatory diseases.1 Cardiac rehabilitation (CR) is recommended by the UK Department of Health and Social Care, the National Institute for Health and Care Excellence (NICE) and the British Association for Cardiovascular Prevention and Rehabilitation (BACPR) for eligible patients following a cardiovascular event. Components of CR focus on health behaviour change and education, lifestyle risk factor management and psychosocial management.2 CR has been shown to be a cost-effective intervention that leads to a reduction in cardiovascular mortality and risk of hospital admissions, while also improving health-related quality of life.3,4

Mental health provision in cardiac rehabilitation

The psychological impacts of CVD are considerable, with patients reporting high levels of anxiety and depression that have been linked to increased mortality, poorer quality of life, greater social problems and higher healthcare costs. In a recent analysis,5 19% of patients entering CR were classed as having borderline or clinical depression and 28% were classed as having borderline or clinical anxiety on the Hospital Anxiety and Depression Scale (HADS). An analysis of health records showed that 54.5% of CVD patients who reported consistently high levels of anxiety and depression were referred to a specialist or had active psychological management with a general practitioner (GP).6 There is no standardised approach for psychological interventions in CR, and interventions can vary between stress management, counselling, relaxation, meditation and cognitive challenging of negative thoughts. Research on psychological interventions within CR is generally of low quality, with usually small reductions of psychological symptoms reported and limited improvement seen in anxiety, low mood and health-related quality of life.7

Novel applications of metacognitive therapy: a translational approach

Metacognitive therapy (MCT)8 is a treatment approach based on the hypothesis that anxiety and depression are maintained by a common maladaptive thinking style, called cognitive attentional syndrome (CAS), of sustained, repetitive negative thinking, increased attention to threat and dysfunctional coping mechanisms. CAS is linked to biased metacognition, which is that part of cognition responsible for regulating thinking. Important components of metacognition are the beliefs a person holds about thinking, which in the metacognitive model can be defined as positive or negative. Positive metacognitive beliefs concern the usefulness of worry as a coping strategy (e.g. ‘worrying helps me find answers to my problems’), whereas negative metacognitive beliefs concern the uncontrollability and danger of thoughts and feelings (e.g. ‘I cannot stop worrying about the future’ or ‘thinking like this means I am losing my mind’). Such beliefs are considered to underlie unhelpful reactions to negative thoughts about life events, such as the thought ‘what if I have another heart attack?’. In comparison with other treatment approaches, MCT does not require in-depth analysis and challenging of the content of negative thoughts or worry, instead focusing on reducing unhelpful processing styles (e.g. reducing worry frequency and duration) in response to negative thoughts.8 MCT has been demonstrated as highly effective in reducing symptoms of anxiety, depression and maladaptive metacognitions in people with mental health problems.9–12 In a recent meta-analysis in mental health, MCT was found to be more effective in reducing anxiety and depression symptoms than other psychological therapies such as cognitive–behavioural therapies (CBT).13

The chief investigator of this programme of research, Adrian Wells, is the originator of MCT and the director of the Metacognitive Therapy Institute. Therefore, it is important to draw attention to the steps taken throughout the PATHWAY research programme to maintain objectivity. These steps included masking to patient allocation, data management undertaken by a separate clinical trials unit, prespecified data analysis plans, pre-trial registration, the publication of trial protocols and project monitoring by an independent Trial Steering Committee (TSC).

The PATHWAY study

Current CR approaches vary considerably in the level and type of psychological interventions used, with many CR services offering little or no psychological input. Furthermore, trials investigating the efficacy of specific psychological interventions and techniques in heart disease are often of low quality.7 In line with guidelines from BACPR, CR programmes offer a choice of treatment approaches in order to deliver a menu-based strategy to meet individual patient needs.2 Currently, 75.4% of patients choose to undertake group-based CR, with 8.8% choosing home-based treatment, while 42.2% of patients engage with two or more modes of CR delivery.5 Therefore, psychological interventions might offer similar variation in treatment delivery, providing the option for group- and home-based treatment to be integrated into existing CR and to maintain improved access to psychological treatment.

The PATHWAY programme aimed to improve access to more effective psychological interventions for patients attending CR services. This was approached through investigating the effects associated with introducing MCT alongside CR in group- and home-based formats.

Aims and objectives of PATHWAY

The primary aim of PATHWAY was to improve access to more effective psychological interventions for a range of heart disease patients attending CR services. We aimed to integrate two metacognitive interventions: a group intervention and a home-based intervention. The project set out to achieve the following objectives:

1. Conduct a pilot randomised controlled trial (RCT) of a group MCT (Group-MCT) for patients with depression and/or anxiety.
2. Establish evidence for the effectiveness and cost-effectiveness of Group-MCT in a full- scale RCT.
3. Produce a rigorous, well-specified Group-MCT package.
4. Develop a home-based metacognitive intervention (Home-MCT) for patients with depression and/or anxiety.
5. Establish the feasibility and acceptability of integrating Home-MCT into the CR pathway.
6. Establish provisional evidence of the effectiveness and cost-effectiveness of Home-MCT.
7. Develop a protocol and manual to inform a full-scale RCT of Home-MCT.

To meet these objectives, we developed a series of work streams (WSs) with integrated qualitative and health economic evaluations. Figure 1 shows the research pathway diagram and Table 1 gives an overview of the original programme objectives, WSs and outputs.

FIGURE 1 Research pathway diagram. (Figure not reproduced here; see the original article.)

Work stream 1 was a pilot trial of Group-MCT for patients with depression and/or anxiety. We undertook an initial small-scale pilot trial to establish the acceptability to CR patients and therapists (CR staff trained to deliver the manualised MCT treatment) of adding MCT to usual CR. The pilot also evaluated the feasibility of conducting a full-scale RCT of the intervention.

Work stream 2 was a full-scale RCT to evaluate the effectiveness and cost-effectiveness of Group-MCT plus usual CR compared with usual CR alone. Progression to WS2 depended on the findings of WS1 with regard to the acceptability and feasibility of delivering MCT and implementing a full-scale RCT.

Work stream 3 was to develop a home-based MCT intervention (Home-MCT) and then evaluate the acceptability and feasibility of integrating Home-MCT into the CR pathway in a feasibility trial.

We were able to fully meet the programme objectives:

• WS1 demonstrated that a trial of Group-MCT added to usual CR was feasible and acceptable and confirmed our original sample size estimate.
• The WS2 and WS3 trials recruited to target and had excellent retention.
• Group-MCT + CR was found to be more effective than CR alone at 4- and 12-month follow-up.
• Home-MCT + CR was found to be feasible and acceptable and was extended to a full-scale trial under a variation to contract (VTC) to utilise a study underspend.
• The full-scale trial of Home-MCT demonstrated that the treatment was associated with significantly improved psychological outcomes when added to usual CR.
• We co-designed the Home-MCT intervention with patients and clinicians.
• We completed a cost-effectiveness analysis of group- and home-based MCT.