Internet based cognitive behaviour therapy and its associations to changes in self-efficacy, depressive symptom and physical activity in patients with cardiovascular disease – a secondary analysis of data collected in a randomized controlled trial (Preprint)

Abstract

In patients with cardiovascular disease (CVD) there is a knowledge gap about the associations between changes in depressive symptoms, self-efficacy and self-care activities. Knowledge about these associations is of importance, as there have been requests for behavioural interventions that could improve self-efficacy, reduce depressive symptoms and improve performance of self-care activities in CVD patients.

To evaluate if internet-based cognitive behavioural therapy (iCBT) improves self-efficacy, and to explore the relationships between changes in depressive symptoms, self-efficacy and physical activity, as well as the influence of iCBT on these relationships.

A secondary analysis of data collected in a randomized controlled study evaluating the effects of a nine-week iCBT programme compared to an online discussion forum on depressive symptoms in patients with CVD (n=144). Data were collected at baseline and at a post-treatment following the nine-week intervention period. Analysis of covariance was used to evaluate if there was a significant difference in self-efficacy between the groups. Structural equation modelling analyses were used to explore the relationships between changes in depressive symptoms, self-efficacy and physical activity and the influence of iCBT on these relationships.

At follow-up, a significant difference in the increase in self-efficacy in favour of iCBT was found (P=.04 Cohen’s d=.27). Structural equation modelling revealed an indirect association between changes in depressive symptoms and physical activity (β=-.24, P<.01), with change in self-efficacy as the mediator. Adding iCBT to the model showed that iCBT had a direct effect on change in depressive symptom, which in turn influenced the changes in self-efficacy (β=.23, P<.001) and physical activity (β=.12, P<.001).

Self-efficacy was improved by iCBT. The influence of iCBT on self-efficacy and physical activity was, however, mostly mediated by improvements in depressive symptoms.

Main trial study is registread at clinicaltrials.gov NCT02778074; https.//clinicaltrials.gov/ct2/show/NCT02778074