Anatomy of a Failure: Can a Cognitive-Bias Modification Intervention Improve Physical Activity in Patients Following a Cardiac Rehabilitation Programme?

Objectives

Promoting regular physical activity (PA) is essential in cardiac rehabilitation; yet many patients exhibit low levels of PA. In January 2022, the Improving Physical Activity (IMPACT) trial, a randomised controlled trial at the University Hospital of Geneva, was launched to promote PA in cardiac patients by targeting automatic approach tendencies towards exercise-related stimuli through a cognitive bias modification (CBM) intervention. This article examines the limited acceptance of this intervention, identifies potential barriers, and proposes strategies to improve future implementations.

Design

Retrospective acceptance evaluation of a pre-registered clinical trial.

Setting

The intervention was conducted in a cardiac rehabilitation centre in Switzerland.

Participants

Sixty-eight cardiac rehabilitation patients ( M _age = 57.76 ±□10.76 years, 87% male).

Intervention

Patients received 12 CBM sessions over 6 weeks, designed to target approach-avoidance tendencies to exercise-related stimuli and improve PA levels.

Primary and secondary outcome measures

Acceptance was assessed using behavioural (e.g., enrolment and engagement rates), cognitive (e.g., perceived effectiveness), and emotional (e.g., affective evaluation) indicators.

Results

Of the 352 patients initially required, only 68 (19%) were enrolled. Among these 68, 17% completed the minimum number of CBM sessions, and 7% completed accelerometer-based PA measures during the week following discharge. These behavioural indicators of low acceptance were complemented by patients’ verbal reports, which showed cognitive (e.g., scepticism about the task relevance and perceived effectiveness of the intervention) and emotional (e.g., feelings of boredom and disinterest) barriers.

Conclusion

The IMPACT trial’s inability to recruit and retain sufficient participants hindered the evaluation of its effectiveness in promoting PA among cardiac patients. These challenges highlight the importance of addressing patients’ perceptions of the task’s relevance and the satisfaction derived from it in order to improve intervention acceptance. Recommendations for improving behavioural, cognitive, and emotional acceptance are discussed, with the aim of increasing the effectiveness of rehabilitation programmes.

Strengths and limitations of this study

• Developing innovative intervention to promote PA in cardiac rehabilitation is essential.

• The intervention involved a computerised intervention targeting automatic precursors of PA behaviours

• Low enrolment and engagement rates limit the ability to assess the effectiveness of the intervention.

• The study identifies key barriers to acceptance, including cognitive (e.g., scepticism) and emotional (e.g., lack of motivation) factors, which hinder engagement.

• The retrospective, unplanned, and unsystematic nature of the measures may introduce recall bias, reducing the validity and accuracy of the reported indicators.