Review question
We reviewed the evidence for the effect of psychological interventions on the psychological impact and quality of life among women with non-metastatic breast cancer (that is cancer that has not spread beyond the breast). Cochrane Review authors collected and analysed all relevant studies to answer these questions and found 60 studies.
Background
Breast cancer is the most common cancer affecting women worldwide. Being a distressing diagnosis, considerable research has examined the psychological consequences of being diagnosed and treated for breast cancer. Breast cancer diagnosis and treatment can cause depression and anxiety and reduce the quality of life. As a result, various psychological interventions have been used to help address the psychological distress experienced after a diagnosis of breast cancer.
Study characteristics
The evidence was current to March 2021. An intervention could be delivered in a group setting (group intervention), as one-to-one contact between a therapist and a patient (individual intervention), or in the form of couple therapy where the patient and her spouse attend the therapy sessions (couple intervention). The control group could receive educational leaflets or have access to seminars or relaxation classes.
A comprehensive search of the literature was conducted and 60 studies comprising 7998 participants were included. The majority of interventions were based on cognitive behavioural therapy, which involves changing a person's thoughts and behaviour. Generally, the methods for assessing outcomes (such as anxiety, depression, quality of life) after the intervention and the timing of these assessments were not uniform across studies.
Key results
Women who received psychological therapy showed reductions in depression, anxiety, mood disturbance and stress, as well as an improvement in quality of life compared to the control group. The effect of psychological therapy on coping and survival could not be determined because very few studies collected or reported these outcomes.
Adverse events were not reported or studied in any of the included studies.
Further research should aim to provide evidence for people to make informed decisions about whether the effects of these treatments are sustainable after discontinuation of the therapy.
Certainty of the evidence
The evidence for each outcome was low certainty. The interventions varied between studies as did the methods and timing of outcome measures and care received within the control groups.
Based on the available evidence, psychological intervention may have produced favourable effects on psychological outcomes, in particular depression, anxiety, mood disturbance and stress. There was also an improvement in quality of life in the psychological intervention group compared to control group. Overall, there was substantial variation across the studies in the range of psychological interventions used, control conditions, measures of the same outcome and timing of follow-up.
Breast cancer is the most common cancer affecting women worldwide. It is a distressing diagnosis and, as a result, considerable research has examined the psychological sequelae of being diagnosed and treated for breast cancer. Breast cancer is associated with increased rates of depression and anxiety and reduced quality of life. As a consequence, multiple studies have explored the impact of psychological interventions on the psychological distress experienced after a diagnosis of breast cancer. This review is an update of a Cochrane Review first published in 2015.
To assess the effect of psychological interventions on psychological morbidities and quality of life among women with non-metastatic breast cancer.
We searched the Cochrane Breast Cancer Group Specialised Register, CENTRAL, MEDLINE, Embase, CINAHL, PsycINFO, the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) and ClinicalTrials.gov up to 16 March 2021. We also scanned the reference lists of relevant articles.
Randomised controlled trials that assessed the effectiveness of psychological interventions for women with non-metastatic breast cancer.
Two review authors independently appraised, extracted data from eligible trials, and assessed risk of bias and certainty of the evidence using the GRADE approach. Any disagreement was resolved by discussion. Extracted data included information about participants, methods, the intervention and outcomes.
We included 60 randomised controlled trials comprising 7998 participants. The most frequent reasons for exclusion were non-randomised trials and the inclusion of women with metastatic disease. The updated review included 7998 randomised women; the original review included 3940 women.
A wide range of interventions was evaluated. Most interventions were cognitive- or mindfulness-based, supportive-expressive, and educational. The interventions were mainly delivered face-to-face (56 studies) and in groups (50 studies) rather than individually (10 studies). Most intervention sessions were delivered on a weekly basis with an average duration of 14 hours. Follow-up time ranged from two weeks to 24 months.
Pooled standardised mean differences (SMD) from baseline indicated that the intervention may reduce depression (SMD -0.27, 95% confidence interval (CI) -0.52 to -0.02; P = 0.04; 27 studies, 3321 participants, I2 = 91%, low-certainty evidence); anxiety (SMD -0.43, 95% CI -0.68 to -0.17; P = 0.0009; 22 studies, 2702 participants, I2 = 89%, low-certainty evidence); mood disturbance in the intervention group (SMD -0.18, 95% CI -0.31 to -0.04; P = 0.009; 13 studies, 2276 participants, I2 = 56%, low-certainty evidence); and stress (SMD -0.34, 95% (CI) -0.55 to -0.12; P = 0.002; 8 studies, 564 participants, I2 = 31%, low-certainty evidence). The intervention is likely to improve quality of life in the intervention group (SMD 0.78, 95% (CI) 0.32 to 1.24; P = 0.0008; 20 studies, 1747 participants, I2 = 95%, low-certainty evidence). Adverse events were not reported in any of the included studies.