Discussion
CAS, anxiety, CVD, cognitive attentional syndrome, depression, trauma
CVD, SECONDARY
This trial showed that the addition of a home-based self-help MCT significantly reduced overall anxiety and depression symptoms (total HADS) in CVD patients undergoing cardiac rehabilitation. Significantly greater improvement was observed in the primary outcome, HADS total at 4-months and in most secondary outcomes. Post-traumatic stress symptoms (secondary psychological outcome) appeared to respond particularly well in the self-help MCT condition. These outcomes showed for the first time that self-help MCT was an effective intervention when added to CR, across anxiety, depression, and trauma symptoms in patients with CVD.An analysis of separate HADS subscales indicated greater improvements in both anxiety and depression symptoms in the MCT group. However, it should be noted that the treatment effect on anxiety was smaller and not significant under MI and LOCF sensitivity analyses accounting for attrition. All other significant effects were robust against sensitivity analyses.The HADS effect sizes were lower than those obtained in our previously published face-to-face group based MCT trial of CR patients [Compared to treatment as usual, the home-based treatment had a significantly greater effect on underlying psychological mechanisms considered to contribute to excessive and chronic anxiety and depression symptoms. We found greater improvements in worry, rumination, and unhelpful coping behaviours, as well as greater reductions in maladaptive metacognitive beliefs (total MCQ score and uncontrollability and danger subscale). It is notable that while the controlled effect for metacognitive beliefs is only slightly smaller in this study compared to our earlier group-MCT intervention study, the effect on the cognitive attentional syndrome (CAS) measure is seemingly lower here. In the present study, the SMD for CAS was 0.43 and this compares with an SMD of 0.73 in our earlier therapist delivered group intervention. The reduced impact on causal mechanisms (CAS, i.e., worry, rumination, unhelpful coping) might account for the reduced effectiveness of self-help MCT on HADS compared with the effects observed in our earlier study of face-to-face group MCT.Twenty-four percent of participants returning the end of treatment questionnaire completed less than 4 Home-MCT modules and attrition from the study was significantly higher in the MCT+CR arm. Hence, it appears that Home-MCT did not appeal to some patients. Nevertheless, the completion rates of Home-MCT compare favourably to previous studies of psychological guided self-help interventions. For example, Lundgren and colleagues [The results we obtained compare favourably with the results of other studies that have used a range of treatment techniques. In a study similar to the present study, Lewin and colleagues [We failed to find a significant effect on EQ-5D utility scores, although the 