Mind-body intervention and CBT for insomnia in breast cancer survivors

Abstract

Comorbid chronic insomnia was found highly prevalent in breast cancer patients. It also persisted through survivorship. Negative emotions upon diagnosis and during the course of cancer treatment might complicate the underlying mediating factors between stress and insomnia found in non-cancer population. Cognitive Behavioural Therapy (CBT) has been evidenced in improving insomnia. With the appreciation of Mindfulness training in improving cognitive flexibility and rumination, a novel treatment approach integrating CBT and mindfulness—Mind-Body Intervention (MBI) was developed. There were three objectives in the research. Firstly, prevalence data on insomnia and clinical profile of Hong Kong Chinese breast cancer survivors were obtained. Secondly, the mediating roles of negative emotions, hyperarousal, pre-sleep arousals in the relationship between perceived stress and insomnia were examined. Thirdly, the effects of CBT and MBI for breast cancer survivors with insomnia were investigated. In the first study, 1049 women who survived from non-metastatic breast cancer were invited to complete a survey on stress, mental health, arousals and insomnia. Those who met psychophysiological insomnia were invited to participate in the second study, which was a multisite randomized controlled trial. The 73 participants were allocated to CBT (n=24), MBI (n=27) or waiting list control, WLC (n=22). Both treatments were five weekly-session group therapies. Outcomes on insomnia, mental health, arousals, dysfunctional beliefs, quality of life and mindfulness, were obtained on baseline, post-treatment, 3-month and 6-month follow-ups. Results of the first study revealed 34.6% of the participants suffered from clinical insomnia, while 15.1%, 27.4% and 12.8% endorsed moderate to extremely severe depression, anxiety and stress respectively. Duration of insomnia was correlated with insomnia severity. Hyperarousal was found moderating cognitive ore-sleep arousal and anxiety, these in turn, together with depression mediated the relationship between perceived stress and insomnia severity. Results of the second study supported the hypothesis both CBT and MBI improved insomnia and other psychological symptoms, while WLC did not. After treatment, significant decreases of 59 and 67 minutes of total wake time per night were found for CBT and MBI respectively. Sleep efficiency values significantly increased in CBT (12.2%) and MBI (12.7%). Moderate to large effect sizes and clinically significant differences were found in most sleep and psychological variables. Generally, CBT produced larger effect sizes than MBI on post-treatment. The therapeutic gains were found sustaining through 3-month to 6-month follow-ups in both treatments. However, the effect sizes of CBT were on the declining trend, while those of MBI were more stable. The results suggested that insomnia and anxiety were frequently experienced in breast cancer even after completing the medical treatments. The longer the survivors suffered from insomnia, the higher the severity was found. In additional to the cognitive pre-sleep arousal, the important mediating roles of depression and anxiety imply that insomnia treatments should incorporate strategies designed to help in decreasing rumination/worry before bedtime and improving mental health conditions. The findings also provided initial evidence for the efficacy of MBI as a viable treatment for insomnia. More vigorous randomized controlled trial and the long-term efficacy could be further studied.