Effects of internet-delivered cognitive behavioral therapy for patients with cardiovascular disease and depression on quality of life. A sub-analysis of a randomized controlled trial

Abstract

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Swedish Research Council (2015-02600), ALF grants Region Östergötland (LIO-600321 and LIO-687531) Background In patients with cardiovascular disease (CVD), depression can cause poorer Health-Related Quality of Life (HRQoL). However, less is known about whether changes in depression over time are associated with changes in HRQoL. We have recently shown that a 9-week internet-based cognitive behavioral therapy (iCBT) program had a significant positive treatment effect on depression in CVD patients and that this effect was maintained at 12-month follow-up. If long-term improvements in depression corresponded to improvements in HRQoL was however not investigated. Purpose To explore if changes in depression after 9 weeks of iCBT are associated with changes in HRQoL at 12 months follow-up. Methods This study is a sub-analysis of a randomized controlled trial evaluating the effects of a nine-week iCBT program for depression in CVD patients. Data from patients who had performed iCBT were analyzed (n=72). Patient Health Questionnaire-9 (PHQ-9) was used to measure depression. The 12-Item Short Form Health Survey (SF12) including the Mental Component Score (MCS) and the Physical Component Score (PCS), and the EQ Visual Analogue Scale (EQ-VAS) were used to measure HRQoL. Data was collected at baseline, 9 weeks, 6 months, and 12 months. Linear mixed model was used to explore long-term treatment effects on HRQoL. Pearson correlation was used to explore the association between changes in depression and HRQoL at 12-month follow-up. Results There was a significant improved treatment effect of iCBT on HRQoL after 12-months (MCS p<.001, PCS p<.032, and EQ-VAS p<.001). Decreased depression was correlated with improved HRQoL after 12-months. The correlation scores between changes in depression and HRQoL were: MCS p<.001, r=-0.62; PCS p<.001, r=-.34; and EQ-VAS r=-.57, p<.001respectively. Conclusion Long term improvement in depression was associated with improvement in HRQoL (Figure 1). Interventions that improve depression in CVD patients are also likely to have sustained positive effect on HRQoL.