Effects of mindfulness-based therapy for patients with breast cancer: A systematic review and meta-analysis

Highlights

• To quantify the effects of mindfulness-based therapy (MBT) in breast cancer patients.

• MBT appears to be effective for breast cancer patients to manage negative emotions.

• MBT might be beneficial in improving physical health of breast cancer patients.

• MBT might be associated with better quality of life of breast cancer patients.

• The evidence is supported but limited for the use of MBT in managing breast cancer.

Abstract

Objective

To quantify the effects of mindfulness-based therapy (MBT) on physical health, psychological health and quality of life (QOL) in patients with breast cancer.

Method

Studies were identified through a systematic search of six electronic databases. Randomized control trials (RCTs) examining the effects of MBT, versus a control group receiving no intervention on physical health, psychological health and QOL in breast cancer patients were included. Two authors independently assessed the methodological quality of included studies using a quality-scoring instrument developed by Jadad et al. and extracted relevant information according to a predesigned extraction form. Data was analysed using the Cochrane Collaboration’s Revman5.1.

Result

Finally, seven studies involving 951 patients were included. While limited in power, the results of meta-analysis indicated a positive effect of MBT in reducing anxiety [SMD −0.31, 95% CI −0.46 to −0.16, P < 0.0001], depression[SMD −1.13, 95% CI −1.85 to −0.41, P = 0.002], fear of recurrence[SMD −0.71, 95% CI −1.05 to −0.38, P < 0.0001], and fatigue[SMD −0.88, 95% CI −1.71 to −0.05, P = 0.04] associated with breast cancer, and improving emotional well-being [SMD 0.39, 95% CI 0.19–0.58, P = 0.0001], physical function[SMD 0.42, 95% CI 0.19–0.65, P = 0.0004], and physical health [SMD 0.31, 95% CI 0.08–0.54, P = 0.009] in these patients. Although the effects on stress, spirituality, pain and sleep were in the expected direction, they were not statistically significant (P > 0.05). Moreover, there is limited evidence from a narrative synthesis that MBT can improve QOL of breast cancer patients.

Conclusion

The present data indicate that MBT is a promising adjunctive therapy for patients with breast cancer. Due to some methodological flaws in the literature, further well-designed RCTs with large sample sizes are needed to confirm these preliminary estimates of effectiveness.

Introduction

Breast cancer is the most frequently diagnosed cancer and the most common cause of cancer death in females worldwide.1, 2 The potential causes of breast cancer remain unclear, despite intense studies were conducted. Recently, due to dramatic advances in medical care, early detection and improved diagnosis and treatment, more and more women are surviving breast cancer each year.3, 4, 5 Some researches reported that the 5-year survival rate for all stages of breast cancer has reached 85% or higher in many countries.4, 6, 7 However, for many breast cancer survivors, the disease itself, or its treatment (e.g., mastectomy, radiation therapy, chemotherapy and hormonal treatments, used alone or in combination), continues to have a profound impact on their daily life. They were not only inevitably experiencing a range of physical symptoms like pain, fatigue, and sleep disturbances, but also dealing with the existential, psychological and social difficulties brought on by their situations.8, 9, 10, 11, 12, 13, 14 All of these may contribute to disease progression and recurrence, which have a substantial impact on an individual’s quality of life (QOL). However, patients may be reluctant to add further analgesics, hypnotics and antidepressants to the numerous agents necessary for basic management of breast cancer. Therefore, to improve the QOL of breast cancer survivors and negate the associated health burdens and risks, non-pharmacological methods, such as psychotherapy, complementary therapies and diet therapy, are required.¹⁵ One increasingly popular type of these methods to support people who are living with cancer is the mindfulness-based therapy (MBT).

MBT is a clinical application of principles found in Buddhism and other spiritual practices, involving the key element of nonjudgmental acceptance of physical pain or psychological distress, thereby reducing the tendency to ruminate over and catastrophise these experiences.¹⁶ Jon Kabat-Zinn, who introduced mindfulness techniques to the West in the nineteen eighties, has defined mindfulness as: ‘the awareness that emerges through paying attention on purpose, in the present moment, and non-judgmentally to the unfolding of experience moment by moment’.17, 18 A conceptual model regarding mindfulness, identify ‘re-perceiving’, briefly explained as a process of change in relation to perceived experience, in turn leading to cognitive-behavioral changes in terms of altered self-regulation, to be the mechanism by which mindfulness training increases well-being.¹⁹

Two of the main mindfulness-based approaches include Mindfulness-Based Stress Reduction (MBSR) and Mindfulness Based Cognitive Therapy (MBCT).²⁰ MBSR classically consists of instruction in three meditation techniques, namely breath awareness, body awareness, and dynamic yoga postures (mindful movement) taught in groups over 8 weeks.¹⁸ MBSR was originally developed for the management of chronic pain and now used widely to reduce psychological morbidity associated with chronic illnesses and to treat emotional and behavioral disorders.²¹ It is the most well researched MBT approach. MBCT is a derivative of MBSR, with a greater emphasis on cognitive techniques, designed for specific mental health conditions such as recurrent depression.²²

Over recent years, the growing number of research projects investigating this approach attests to the benefits of mindfulness in helping cancer people improve their physical and mental health. Results from this relevant literature indicated that MBT was beneficial to reduce a variety of psychosocial cancer symptoms.23, 24, 25, 26 The effectiveness of MBT specifically for patients with breast cancer has been systematically reviewed by Cramer et al. and Zainal et al.27, 28 Zainal et al. examined the effects of MBSR solely on mental health of breast cancer patients.²⁷ The results showed that MBSR had a positive effect on the reduction of stress, anxiety and depression. Similarly, Cramer et al. confirmed the positive impact of MBSR on decreasing anxiety and depression in patients with breast cancer.²⁷ However, in both of these reviews, only two RCTs with small samples were included, which limited the possibility of pooling other outcomes. Until now, it is not entirely clear whether MBT is effective for patients with breast cancer.

Therefore, the present review and meta-analysis aims to summarize the evidence, specifically examining the effects of MBT on physical health, psychological health and QOL in patients with breast cancer, in order to inform decisions about recommendations for overall treatment.