Predictors of poor exercise self-efficacy improvements after cardiac rehabilitation

ABSTRACT

Background/Introduction: Building confidence to exercise regularly (exercise self-efficacy (ESE)) in the face of constraints and barriers, is a key goal of cardiac rehabilitation (CR) because such self-efficacy beliefs are predictors of sustained exercise behaviours. Therefore, identifying patient subgroups at risk of poor ESE enables tailoring of CR and appropriate targeting of support interventions. Purpose: To identify independent predictors of poor ESE and poor improvements in ESE in CR participants. Methods: The study used a prospective observational cohort design and recruited patients with coronary heart disease at CR entry across four sites in Metropolitan Sydney, Australia (2019-2020). Data were also compared for traditional in-person and remote-delivered CR during COVID-19 pandemic restrictions. The Exercise Self Efficacy Scale was used to measure ESE at CR entry and completion, and General Linear Models were used for analyses. Results: Participants (n=194) had a mean age of 65.94 (SD 10.46) years, with 80.9% males;and 80.0% were married or partnered, with 23.6% from an ethnic minority background. Referral diagnosis included elective percutaneous coronary intervention (PCI) (40.2%), coronary artery bypass surgery (26.3%), and myocardial infarction with or without PCI (33.5%). At CR entry, the mean ESE score was 24.93 (SD 5.99) points, which improved significantly by completion (p=.027). The GLM of ESE change (Adjusted R2=.247) identified that predictors of less change in ESE scores by CR completion included ethnic minorities (β=2.96, p=.003), not having a spouse or an intimate partner (β=-2.42, p=.023), and attending in-person CR (β=1.75, p=.036). Having higher ESE scores at entry was also associated with less ESE change on completion, such that for every point increase in ESE at entry, there was a reduction of .37 points in change (p<.001). These variables were also the same predictors of poor ESE at CR completion. Conclusions: Confidence to exercise improves in CR, and screening for ESE at CR entry enables identification of patients at-risk of poor improvements. Tailoring of interventions to provide appropriate support such as extending CR should be considered for patients from ethnic minorities and those who are single/widowed. Exploring the reasons for differences in outcomes from in-person and remote-delivered CR using appropriate methods should be the focus of future research.